阅读说明：本技术 粘合片粘贴方法、粘合片粘贴装置和半导体产品的制造方法 (Adhesive sheet sticking method, adhesive sheet sticking apparatus, and method for manufacturing semiconductor product ) 是由 秋月伸也 山本雅之 于 2021-05-27 设计创作，主要内容包括：本发明提供能够相对于形成有环状凸部的半导体晶圆的环状凸部形成面精度良好地粘贴粘合片并能更可靠地避免在半导体晶圆产生损伤的粘合片粘贴方法、粘合片粘贴装置和半导体产品的制造方法。该粘合片粘贴方法具备：第1粘贴过程,在该第1粘贴过程中,将粘合带(DT)和在一个面的外周具有环状凸部(Ka)的晶圆(W)收纳于腔室(29),在将腔室(29)的内部空间减压了的状态下使粘合带(DT)接触于晶圆(W)的环状凸部形成面,由此利用粘合带(DT)覆盖该环状凸部形成面；以及第2粘贴过程,该第2粘贴过程是在该第1粘贴过程之后,通过提高腔室(29)的内部空间的压力,从而将粘合带(DT)粘贴于晶圆(W)的环状凸部形成面。(The invention provides an adhesive sheet sticking method, an adhesive sheet sticking apparatus and a semiconductor product manufacturing method, which can stick an adhesive sheet to an annular convex part forming surface of a semiconductor wafer with an annular convex part with good precision and can reliably avoid damage to the semiconductor wafer. The adhesive sheet sticking method comprises: a first bonding step (1) in which an adhesive tape (DT) and a wafer (W) having an annular projection (Ka) on the outer periphery of one surface are housed in a chamber (29), and the annular projection-formed surface of the wafer (W) is covered with the adhesive tape (DT) by bringing the adhesive tape (DT) into contact with the annular projection-formed surface of the wafer (W) while reducing the pressure in the internal space of the chamber (29); and a 2 nd bonding step of bonding the adhesive tape (DT) to the annular convex portion forming surface of the wafer (W) by increasing the pressure in the internal space of the chamber (29) after the 1 st bonding step.)

1. A method for sticking an adhesive sheet, characterized in that,

the adhesive sheet sticking method comprises:

a first bonding step 1 of housing a pressure-sensitive adhesive sheet and a workpiece having an annular projection on an outer periphery of one surface thereof in a chamber, and bringing the pressure-sensitive adhesive sheet into contact with an annular projection-forming surface of the workpiece while reducing an internal space of the chamber, thereby covering the annular projection-forming surface with the pressure-sensitive adhesive sheet; and

and a 2 nd adhesion step of adhering the adhesive sheet to the annular convex portion forming surface by increasing a pressure in the internal space of the chamber after the 1 st adhesion step.

2. The adhesive sheet application method according to claim 1,

in the first attaching step 1, the adhesive sheet is deformed into a convex shape toward the annular convex portion forming surface of the workpiece, whereby the adhesive sheet is brought into contact with the annular convex portion forming surface of the workpiece.

3. The adhesive sheet application method according to claim 1,

in the 2 nd pasting process, the pressure of the inner space of the chamber is raised to a pressure higher than atmospheric pressure.

4. The adhesive sheet application method according to claim 2,

the chamber is provided with an upper shell and a lower shell,

the 1 st pasting process has:

a vertical space forming step of dividing an internal space of the chamber into a lower space in which the workpiece is disposed in a state in which the annular projection forming surface faces upward and an upper space facing the lower space with the adhesive sheet interposed therebetween, by sandwiching the adhesive sheet between the upper case and the lower case;

an upper-lower space decompression process in which the upper space and the lower space are decompressed; and

and a contact step of deforming the adhesive sheet into a convex shape toward the annular convex portion forming surface and contacting the adhesive sheet with the annular convex portion forming surface of the workpiece by a pressure difference between the upper space and the lower space caused by the pressure in the upper space being higher than the pressure in the lower space after the upper and lower space pressure reduction step.

5. The adhesive sheet application method according to claim 2,

the chamber is provided with an upper shell and a lower shell,

the 1 st pasting process has:

a vertical space forming step of dividing an internal space of the chamber into a lower space in which the workpiece is disposed in a state in which the annular projection forming surface faces upward and an upper space facing the lower space with the adhesive sheet interposed therebetween, by sandwiching the adhesive sheet between the upper case and the lower case; and

and a pressure-reducing contact step of deforming the adhesive sheet into a convex shape toward the annular convex portion-formed surface by a pressure difference generated between the upper space and the lower space by reducing the pressure of only the lower space of the upper space and the lower space, and contacting the adhesive sheet with the annular convex portion-formed surface of the workpiece in a state where the lower space is reduced in pressure.

6. The adhesive sheet sticking method according to claim 4 or 5,

the adhesive sheet has a predetermined shape corresponding to the annular projection forming surface of the work and is held by a long sheet for conveyance,

in the process of forming the upper and lower spaces, the conveying sheet is sandwiched between the upper case and the lower case, thereby dividing the internal space of the chamber into a lower space in which the workpiece is disposed in a state in which the annular projection is formed facing upward, and an upper space facing the lower space with the adhesive sheet held by the conveying sheet interposed therebetween.

7. The adhesive sheet sticking method according to claim 4 or 5,

a sheet-like elastic body disposed inside the upper case,

the sheet-shaped elastic body is disposed so as to abut against the adhesive sheet by forming the cavity in the process of forming the upper and lower spaces.

8. The adhesive sheet sticking method according to claim 4 or 5,

the adhesive sheet attaching method includes a heating process in which the adhesive sheet is heated by heating at least one of the lower space and the upper space,

in the first attaching step 1, the adhesive sheet heated in the heating step is brought into contact with an annular projection forming surface of the workpiece.

9. An adhesive sheet sticking apparatus is characterized in that,

the adhesive sheet sticking apparatus includes:

a first sticking mechanism that houses a pressure-sensitive adhesive sheet and a workpiece having an annular projection on an outer periphery of one surface thereof in a chamber, and that covers the annular projection-forming surface with the pressure-sensitive adhesive sheet by bringing the pressure-sensitive adhesive sheet into contact with the annular projection-forming surface of the workpiece while reducing an internal space of the chamber; and

and a 2 nd sticking mechanism for sticking the adhesive sheet to the annular convex portion forming surface by increasing a pressure in the internal space of the chamber after the 1 st sticking mechanism completes its operation.

10. A method for manufacturing a semiconductor product in which an adhesive sheet is adhered to an annular projection forming surface of a work having an annular projection on an outer periphery of one surface of the work,

the method for manufacturing a semiconductor product comprises:

a 1 st adhesion step of accommodating the workpiece and the adhesive sheet in a chamber, and bringing the adhesive sheet into contact with an annular projection forming surface of the workpiece in a state where an internal space of the chamber is depressurized, thereby covering the annular projection forming surface with the adhesive sheet; and

and a 2 nd adhesion step of adhering the adhesive sheet to the annular convex portion forming surface by increasing a pressure in the internal space of the chamber after the 1 st adhesion step.

Technical Field

The present invention relates to an adhesive sheet joining method, an adhesive sheet joining apparatus, and a semiconductor product manufacturing method for joining an adhesive sheet, such as a tape-shaped adhesive material, to a workpiece, such as a semiconductor wafer (hereinafter, appropriately referred to as "wafer") or a substrate.

Background

After forming a circuit pattern on the front surface of the wafer, the back surface of the wafer is ground by a back surface grinding process, and the wafer is divided into a plurality of chip components by a dicing process. In the back grinding step, there are cases where: the outer periphery of the back surface of the wafer is left, and only the central portion is ground, so that an annular convex portion is formed on the outer periphery of the back surface of the wafer so as to surround the back surface grinding region.

In this case, even when the center portion of the wafer is thinned, the wafer is reinforced by the annular convex portion, and therefore, it is possible to avoid occurrence of strain or the like during processing. After the back grinding step, the wafer having the annular convex portion is placed at the center of the ring frame, and an adhesive tape (dicing tape) for supporting is attached across the ring frame and the back surface of the wafer. The mounting frame is manufactured by sticking the cutting tape so as to be used in the cutting process.

As an example of a method for attaching an adhesive sheet such as a dicing tape to a wafer having a step formed by an annular projection, the following method is proposed. That is, the adhesive sheet is sandwiched between the joining portions of the chamber formed by the upper and lower pair of cases. Then, the following processing is performed: the pressure in the chamber is reduced to generate a pressure difference between two spaces partitioned by the adhesive sheet, and the adhesive tape is concavely bent to attach the adhesive sheet to the back surface of the wafer. After the pressure difference in the chamber is eliminated, the adhesive sheet that has not been completely adhered to the inner corner of the annular projection and has floated is supplied with gas from the 1 st pressing member, and the 2 nd application process is performed (see patent document 1).

Patent document 1: japanese patent laid-open publication No. 2013-232582

Disclosure of Invention

Problems to be solved by the invention

However, the conventional apparatus described above has the following problems. That is, the conventional adhesive sheet sticking method has the following problems: after the adhesive sheet is attached, the adhesive sheet is peeled off from the inner corner of the annular projection toward the wafer center with the passage of time. In addition, the conventional method for sticking an adhesive sheet has the following problems: when the adhesive sheet is attached to a wafer, damage such as cracks or chipping occurs in the wafer.

The present invention has been made in view of the above circumstances, and a main object thereof is to provide an adhesive sheet attaching method, an adhesive sheet attaching apparatus, and a semiconductor product manufacturing method, which can attach an adhesive sheet to an annular convex portion forming surface of a semiconductor wafer having an annular convex portion formed thereon with high accuracy and can more reliably avoid damage to the semiconductor wafer.

Means for solving the problems

The present inventors have made studies to solve the above problems, and as a result, have obtained the following findings. That is, in the conventional configuration in which the 2 nd attaching process is performed using the 1 st pressing member, the force acting on the adhesive sheet is small. Therefore, it is difficult to sufficiently improve the adhesion between the wafer and the adhesive sheet, and it is considered that the adhesive sheet peels off from the wafer with the passage of time.

In the 2 nd pasting process, a relatively large pressing force acts on the inner corner of the annular convex portion of the wafer as compared with the central portion of the wafer. It is considered that such a variation in the pressing force causes cracks or chipping at a high frequency particularly in the inner corner portion of the annular convex portion of the wafer to which a relatively large pressing force is applied.

The 1 st pressing member has a gas supply hole and is a columnar member made of metal, resin, or the like. In the conventional structure, the gas is supplied by bringing the bottom surface of the 1 st pressing member close to the wafer. The following situation may arise: by bringing the 1 st pressing member closer, the 1 st pressing member comes into contact with the center portion of the wafer, which has been thinned and formed into a concave shape, and the thin concave portion of the wafer is damaged. It is considered that, when the flatness of the bottom surface of the 1 st pressing member is low, even in a state where the 1 st pressing member is close to the inner corner of the annular convex portion of the wafer, the 1 st pressing member comes into contact with another portion (for example, the central portion) of the wafer, and as a result, the wafer is damaged.

In order to achieve the above object, the present invention has the following aspects.

That is, the present invention provides a method for sticking an adhesive sheet, comprising: a first bonding step 1 of housing a pressure-sensitive adhesive sheet and a workpiece having an annular projection on an outer periphery of one surface thereof in a chamber, and bringing the pressure-sensitive adhesive sheet into contact with an annular projection-forming surface of the workpiece while reducing an internal space of the chamber, thereby covering the annular projection-forming surface with the pressure-sensitive adhesive sheet; and a 2 nd adhesion process of adhering the adhesive sheet to the annular convex portion forming surface by increasing a pressure in the internal space of the chamber after the 1 st adhesion process.

(action/Effect)

In this configuration, in the first attaching step 1, the pressure-sensitive adhesive sheet is brought into contact with the annular convex portion forming surface of the workpiece in a state where the internal space of the chamber is depressurized, thereby covering the annular convex portion forming surface with the pressure-sensitive adhesive sheet. That is, since the peripheral space of the device mounted on the workpiece is depressurized to discharge air, when the adhesive sheet covers the annular projection forming surface of the workpiece, gas can be prevented from being trapped between the adhesive sheet and the workpiece. Therefore, a decrease in the adhesion force due to the entrainment of the gas can be avoided.

In the 2 nd attaching step, the pressure in the internal space of the chamber is increased, whereby the adhesive sheet is attached to the annular projection forming surface of the workpiece. In this case, the pressing force can be uniformly applied to the entire pressure-sensitive adhesive sheet by the pressurization of the internal space. Therefore, it is possible to reliably avoid the occurrence of damage such as cracks or chipping on the annular convex portion forming surface of the workpiece due to variation in force acting on the adhesive sheet.

In addition, in the 2 nd pasting process, the air pressure of the internal space in the 2 nd pasting process can be arbitrarily adjusted by appropriately pressurizing the internal space of the chamber. Therefore, a sufficiently large pressing force can be applied to the adhesive sheet, and the adhesive sheet can be accurately bonded to the annular convex portion formation surface. Therefore, even if time elapses after the 2 nd affixing process is completed, the adhesive sheet can be more reliably prevented from peeling off from the workpiece.

In the invention described above, it is preferable that in the first attaching step 1, the adhesive sheet is deformed into a convex shape toward the annular convex portion forming surface of the workpiece, so that the adhesive sheet is brought into contact with the annular convex portion forming surface of the workpiece.

(action/Effect)

In this case, the adhesive sheet is deformed into a convex shape toward the annular convex portion forming surface of the workpiece, and therefore the adhesive sheet can be brought into contact with the annular convex portion forming surface of the workpiece so as to spread radially from one point. Therefore, it is possible to avoid air bubbles from being involved when the adhesive sheet is brought into contact with the annular projection forming surface.

In the above invention, it is preferable that, in the 2 nd pasting step, the pressure in the internal space of the chamber is increased to a pressure equal to or higher than atmospheric pressure.

(action/Effect)

With this configuration, a relatively large pressing force is applied between the adhesive sheet and the annular projection forming surface of the workpiece, and therefore the adhesion between the annular projection forming surface and the adhesive sheet can be further improved. Therefore, the adhesive sheet can be more reliably prevented from peeling off from the workpiece after the lapse of time.

In the above invention, it is preferable that the chamber includes an upper case and a lower case, and the 1 st adhesion step includes: a vertical space forming step of dividing an internal space of the chamber into a lower space in which the workpiece is disposed in a state in which the annular projection forming surface faces upward and an upper space facing the lower space with the adhesive sheet interposed therebetween, by sandwiching the adhesive sheet between the upper case and the lower case; an upper-lower space decompression process in which the upper space and the lower space are decompressed; and a contact step of deforming the adhesive sheet into a convex shape toward the annular convex portion forming surface and contacting the adhesive sheet to the annular convex portion forming surface of the workpiece by a pressure difference between the upper space and the lower space caused by the pressure in the upper space being higher than the pressure in the lower space after the upper and lower space pressure reduction step.

(action/Effect)

In this embodiment, in the 1 st adhesion step, the upper space and the lower space are depressurized, and the pressure difference generated by making the pressure in the upper space higher than the pressure in the lower space is used to bring the adhesive sheet into contact with the annular convex portion forming surface of the workpiece. That is, since the pressure-sensitive adhesive sheet is brought into contact with the annular projection-forming surface in a state where air in the lower space is discharged by reducing the pressure, air bubbles can be more reliably prevented from being caught between the pressure-sensitive adhesive sheet and the annular projection-forming surface when the pressure-sensitive adhesive sheet is brought into contact with a workpiece. Further, since the pressure difference is uniformly applied to the entire pressure-sensitive adhesive sheet, it is possible to avoid the occurrence of workpiece damage due to variation in applied force.

In the above invention, it is preferable that the chamber includes an upper case and a lower case, and the 1 st adhesion step includes: a vertical space forming step of dividing an internal space of the chamber into a lower space in which the workpiece is disposed in a state in which the annular projection forming surface faces upward and an upper space facing the lower space with the adhesive sheet interposed therebetween, by sandwiching the adhesive sheet between the upper case and the lower case; and a pressure-reducing contact step of deforming the adhesive sheet into a convex shape toward the annular convex portion-formed surface by a pressure difference generated between the upper space and the lower space by reducing the pressure of only the lower space of the upper space and the lower space, and contacting the adhesive sheet to the annular convex portion-formed surface of the workpiece in a state where the lower space is reduced in pressure.

(action/Effect)

In this embodiment, in the first attaching step 1, only the lower space is depressurized, and the pressure difference thus generated is used to bring the adhesive sheet into contact with the annular projection forming surface of the workpiece. That is, since the pressure-sensitive adhesive sheet is brought into contact with the annular projection-forming surface in a state where air in the lower space is discharged by reducing the pressure, it is possible to more reliably avoid air bubbles from being caught between the pressure-sensitive adhesive sheet and the annular projection-forming surface when the pressure-sensitive adhesive sheet is brought into contact with a workpiece. Further, since the pressure difference is uniformly applied to the entire pressure-sensitive adhesive sheet, it is possible to avoid the occurrence of workpiece damage due to variation in applied force. Further, since only the lower space needs to be decompressed, a structure for decompressing the upper space is not necessary. Therefore, complication and high cost of the apparatus can be avoided.

In the above invention, it is preferable that the adhesive sheet has a predetermined shape corresponding to an annular projection forming surface of the workpiece and is held by the long transport sheet, and the transport sheet is sandwiched between the upper case and the lower case in the process of forming the upper and lower spaces, thereby dividing an internal space of the chamber into a lower space in which the workpiece in a state in which the annular projection forming surface faces upward and an upper space facing the lower space via the adhesive sheet held by the transport sheet.

(action/Effect)

With this configuration, the adhesive sheet has a predetermined shape corresponding to the annular projection forming surface of the workpiece in advance. Therefore, the adhesive sheet can be appropriately attached to the annular convex portion forming surface of the workpiece in accordance with the position and shape of the annular convex portion forming surface. Further, since a step of cutting the adhesive sheet into an appropriate predetermined shape or the like is not required, the step of attaching the adhesive sheet can be shortened.

In the above invention, it is preferable that the adhesive sheet further includes a sheet-like elastic body disposed inside the upper case, and the sheet-like elastic body is disposed so as to be in contact with the adhesive sheet by forming the cavity in the process of forming the upper and lower spaces.

(action/Effect)

With this arrangement, the sheet-like elastic body is deformed into a convex shape as a whole at a more uniform bending rate under the action of the pressure difference. Therefore, the adhesive sheet is easily deformed in accordance with the shape of the annular projection forming surface of the workpiece, and adhesion between the annular projection forming surface and the adhesive sheet can be improved. Therefore, the adhesive sheet can be more accurately bonded to the annular projection forming surface.

In the above invention, it is preferable that the adhesive sheet joining method includes a heating step of heating the adhesive sheet by heating at least one of the lower space and the upper space, and in the 1 st joining step, the adhesive sheet in a state heated by the heating step is brought into contact with an annular projection forming surface of the workpiece.

(action/Effect)

With this scheme, the adhesive sheet becomes softer by heating the adhesive sheet with a heating process. That is, the adhesive sheet is easily deformed in accordance with the shape of the annular projection forming surface of the workpiece, and therefore, the adhesion between the annular projection forming surface and the adhesive sheet can be improved.

In order to achieve the above object, the present invention may employ the following configuration.

That is, the present invention provides an adhesive sheet sticking apparatus, comprising: a first sticking mechanism that houses a pressure-sensitive adhesive sheet and a workpiece having an annular projection on an outer periphery of one surface thereof in a chamber, and that covers the annular projection-forming surface with the pressure-sensitive adhesive sheet by bringing the pressure-sensitive adhesive sheet into contact with the annular projection-forming surface of the workpiece while reducing an internal space of the chamber; and a 2 nd attaching mechanism for attaching the adhesive sheet to the annular convex portion forming surface by increasing a pressure in an internal space of the chamber after the 1 st attaching mechanism completes its operation.

(action/Effect)

In this configuration, the first attaching mechanism 1 brings the adhesive sheet into contact with the annular convex portion forming surface of the workpiece in a state where the internal space of the chamber is depressurized, thereby covering the annular convex portion forming surface with the adhesive sheet. That is, since the peripheral space of the device mounted on the workpiece is depressurized to discharge air, when the adhesive sheet covers the annular projection forming surface of the workpiece, gas can be prevented from being trapped between the adhesive sheet and the workpiece. Therefore, a decrease in the adhesion force due to the entrainment of the gas can be avoided.

The 2 nd attaching mechanism attaches the adhesive sheet to the annular convex portion forming surface of the workpiece by increasing the pressure in the internal space of the chamber. In this case, the pressing force can be uniformly applied to the entire pressure-sensitive adhesive sheet by the pressurization of the internal space. Therefore, it is possible to reliably avoid the occurrence of damage such as cracks or chipping on the annular convex portion forming surface of the workpiece due to variation in force acting on the adhesive sheet.

In addition, the 2 nd pasting mechanism arbitrarily adjusts the air pressure of the inner space in the 2 nd pasting process by appropriately pressurizing the inner space of the chamber. Therefore, a sufficiently large pressing force can be applied to the adhesive sheet, and the adhesive sheet can be accurately bonded to the annular convex portion formation surface. Therefore, even if time elapses after the 2 nd affixing process is completed, the adhesive sheet can be more reliably prevented from peeling off from the workpiece.

In order to achieve the above object, the present invention may employ the following configuration.

That is, the present invention provides a method for manufacturing a semiconductor product in which an adhesive sheet is attached to an annular projection forming surface of a workpiece having an annular projection on an outer periphery of one surface, the method comprising: a 1 st adhesion step of accommodating the workpiece and the adhesive sheet in a chamber, and bringing the adhesive sheet into contact with an annular projection forming surface of the workpiece in a state where an internal space of the chamber is depressurized, thereby covering the annular projection forming surface with the adhesive sheet; and a 2 nd adhesion process of adhering the adhesive sheet to the annular convex portion forming surface by increasing a pressure in the internal space of the chamber after the 1 st adhesion process.

(action/Effect)

With this configuration, a semiconductor product can be preferably manufactured in which the adhesive sheet is attached to the annular convex portion forming surface of the workpiece having the annular convex portion on the outer periphery of one surface. That is, in the first attaching step 1, the pressure-sensitive adhesive sheet is brought into contact with the annular convex portion forming surface of the workpiece in a state where the internal space of the chamber is depressurized, thereby covering the annular convex portion forming surface with the pressure-sensitive adhesive sheet. In the 1 st attaching step, the peripheral space of the device mounted on the workpiece is depressurized to discharge air, and therefore, when the adhesive sheet covers the annular projection forming surface of the workpiece, gas can be prevented from being trapped between the adhesive sheet and the workpiece. Therefore, a decrease in the adhesion force due to the entrainment of the gas can be avoided.

In the 2 nd attaching step, the pressure in the internal space of the chamber is increased, whereby the adhesive sheet is attached to the annular projection forming surface of the workpiece. In this case, the pressing force can be uniformly applied to the entire pressure-sensitive adhesive sheet by the pressurization of the internal space. Therefore, it is possible to reliably avoid the occurrence of damage such as cracks or chipping on the annular convex portion forming surface of the workpiece due to variation in force acting on the adhesive sheet.

ADVANTAGEOUS EFFECTS OF INVENTION

In the adhesive sheet application method, adhesive sheet application apparatus, and semiconductor product manufacturing method of the present invention, in the first application step 1, the annular convex portion forming surface of the workpiece is covered with the adhesive sheet by bringing the adhesive sheet into contact with the annular convex portion forming surface in a state where the internal space of the chamber is depressurized. That is, since the peripheral space of the device mounted on the workpiece is depressurized to discharge air, when the adhesive sheet covers the annular projection forming surface of the workpiece, gas can be prevented from being trapped between the adhesive sheet and the workpiece. Therefore, a decrease in the adhesion force due to the entrainment of the gas can be avoided.

In the 2 nd attaching step, the pressure in the internal space of the chamber is increased, whereby the adhesive sheet is attached to the annular projection forming surface of the workpiece. In this case, the pressing force can be uniformly applied to the entire pressure-sensitive adhesive sheet by the pressurization of the internal space. Therefore, it is possible to reliably avoid the occurrence of damage such as cracks or chipping on the annular convex portion forming surface of the workpiece due to variation in force acting on the adhesive sheet.

In addition, in the 2 nd pasting process, the air pressure of the internal space in the 2 nd pasting process can be arbitrarily adjusted by appropriately pressurizing the internal space of the chamber. Therefore, a sufficiently large pressing force can be applied to the adhesive sheet, and the adhesive sheet can be accurately bonded to the annular convex portion formation surface. Therefore, even if time elapses after the 2 nd affixing process is completed, the adhesive sheet can be more reliably prevented from peeling off from the workpiece.

Drawings

Fig. 1 is a diagram showing a structure of a semiconductor wafer according to example 1. Fig. 1 (a) is a partially cut perspective view of a semiconductor wafer, fig. 1 (b) is a perspective view of the back surface side of the semiconductor wafer, and fig. 1 (c) is a partially vertical sectional view of the semiconductor wafer.

Fig. 2 is a sectional view showing the structure of the pressure-sensitive adhesive sheet of example 1.

Fig. 3 is a plan view of the adhesive sheet application apparatus of example 1.

Fig. 4 is a front view of the adhesive sheet application apparatus of example 1.

Fig. 5 is a front view of the pasting unit of embodiment 1.

Fig. 6 is a longitudinal sectional view of the chamber of embodiment 1.

Fig. 7 is a flowchart showing the operation of the adhesive sheet sticking apparatus according to the embodiment.

Fig. 8 is a perspective view of the mount of embodiment 1.

Fig. 9 is a diagram illustrating step S2 of embodiment 1.

Fig. 10 is a diagram illustrating step S3 of embodiment 1.

Fig. 11 is a diagram illustrating step S3 of example 1.

Fig. 12 is a diagram illustrating step S4 of embodiment 1.

Fig. 13 is a diagram illustrating step S4 of example 1.

Fig. 14 is a diagram illustrating step S5 of embodiment 1.

Fig. 15 is a diagram illustrating step S6 of example 1.

Fig. 16 is a diagram illustrating step S6 of embodiment 1.

Fig. 17 is a diagram illustrating step S7 of example 1.

Fig. 18 is a diagram showing the structures of the pressure-sensitive adhesive sheet and the transfer sheet of example 2. Fig. 18 (a) is a perspective view of the back sides of the pressure-sensitive adhesive sheet and the transportation sheet, and fig. 18 (b) is a longitudinal sectional view of the pressure-sensitive adhesive sheet and the transportation sheet.

Fig. 19 is a flowchart showing the operation of the adhesive sheet application apparatus according to example 2.

Fig. 20 is a diagram illustrating step S2 of embodiment 2.

Fig. 21 is a diagram illustrating step S2 of embodiment 2.

Fig. 22 is a diagram illustrating step S3 of embodiment 2.

Fig. 23 is a diagram illustrating step S3 of embodiment 2.

Fig. 24 is a diagram illustrating step S4 of embodiment 2.

Fig. 25 is a diagram illustrating step S5 of embodiment 2.

Fig. 26 is a diagram illustrating step S6 of embodiment 2.

Fig. 27 is a diagram illustrating step S6 of embodiment 2.

Fig. 28 is a diagram illustrating a structure of a modification.

Fig. 29 is a diagram illustrating a structure of a modification. Fig. 29 (a) is a vertical cross-sectional view showing the structure of an adhesive tape and a transport sheet according to a modification, and fig. 29 (b) is a perspective view explaining the structure of a sheet cutting device according to a modification.

Fig. 30 is a diagram illustrating a structure of a modification. Fig. 30 (a) is a vertical cross-sectional view showing a structure provided with an elastic body of a modification, fig. 30 (b) is a view explaining a problem that may occur in a structure without an elastic body, and fig. 30 (c) is a view explaining an advantage in a structure with an elastic body.

Fig. 31 is a diagram illustrating a structure of a modification. Fig. 31 (a) is a vertical sectional view showing a structure including a heating mechanism according to a modification, and fig. 31 (b) is a vertical sectional view explaining an example of a step of heating the adhesive tape by the heating mechanism.

Description of the reference numerals

1. An adhesive sheet sticking device; 3. a wafer conveying mechanism; 5. a container; 6. a rack recovery unit; 7. an aligner; 9. a holding stage; 12. a rack supply section; 13. a pasting unit; 16. a wafer conveying device; 17. a rack transport device; 23. a holding arm; 27. an adsorption plate; 28. a suction cup; 31. a vacuum device; 32. a pressurizing device; 33. a control unit; 38. a rack holding section; 71. a sheet supply section; 72. a separator recovery unit; 73. a sheet sticking section; 74. a sheet recovery unit; 81. a sheet sticking mechanism; 82. a sheet cutting mechanism; 85. a pasting roller; 86. a grip roller; 95. a cutter; f. an annular frame; DT, adhesive tape; p, a conveying sheet; MF and a mounting rack; ta, a base material; tb, adhesive material; pa, a base material; pb, binder material.

Detailed Description

[ example 1 ]

Hereinafter, embodiment 1 of the present invention will be described with reference to the drawings. In the adhesive sheet sticking apparatus 1 of example 1, an adhesive tape DT (dicing tape) for support is used as an adhesive sheet, and a semiconductor wafer W (hereinafter, referred to as "wafer W") and a ring frame f are used as a workpiece to which the adhesive sheet is to be stuck. That is, in the adhesive sheet sticking apparatus 1 of example 1, the mount MF is fabricated by sticking the adhesive tape DT across the wafer W and the ring mount f.

As shown in fig. 1 (a) to 1 (c), the wafer W is subjected to a back grinding process while a protective tape PT for protecting a circuit is stuck to the surface of the wafer W on which a circuit pattern is formed. The back surface of the wafer W is ground (back grinding) so that the outer peripheral portion is left by about 3mm in the radial direction. That is, the wafer to be used is processed into a shape in which the flat concave part He is formed on the back surface and the annular convex part Ka is left along the outer periphery of the back surface. For example, the flat concave portion He is ground to a depth d of several hundred μm and the wafer thickness J of the flat concave portion He is 30 to 50 μm. Therefore, the annular convex portion Ka formed on the outer periphery of the back surface functions as an annular rib for improving the rigidity of the wafer W, and suppresses the wafer W from being deformed by bending (handling) or other processing steps. Further, the inside corner of the annular protrusion Ka is denoted by reference numeral Kf. The inside corner Kf corresponds to a boundary between the annular convex portion Ka and the flat concave portion He. The back surface of the wafer W corresponds to the annular projection forming surface of the workpiece in the present invention.

As shown in fig. 2, the adhesive tape DT used in the present example has a long structure in which a non-adhesive base material Ta and an adhesive material Tb having adhesiveness are laminated. The adhesive material Tb is added with a separator S. That is, the release sheet S is attached to the adhesive surface of the adhesive tape DT, and the release sheet S is peeled off from the adhesive tape DT to expose the adhesive surface of the adhesive tape DT.

Examples of the material constituting the base Ta include polyolefin, polyethylene, ethylene-vinyl acetate copolymer, polyester, polyimide, polyurethane, vinyl chloride, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polyvinylidene chloride, polyethylene methacrylate copolymer, polypropylene, methacrylic acid terephthalate, polyamide imide, and polyurethane elastomer. Further, a combination of a plurality of the above materials may be used as the base Ta. The substrate Ta may be a single layer or a multilayer structure.

The adhesive material Tb is preferably made of a material that can maintain the state in which the adhesive tape DT is adhered to the wafer W and the ring frame f, and can prevent the chip components from scattering in the subsequent dicing step. Examples of the material constituting the adhesive material Tb include an acrylate copolymer. Examples of the separator S include long paper and plastic. Instead of the adhesive Tb, an adhesive or a bonding material may be used.

< description of the entire Structure >

Here, the overall configuration of the adhesive sheet sticking apparatus 1 of example 1 will be described. Fig. 3 is a plan view showing the basic configuration of the adhesive sheet sticking apparatus 1 of example 1. The adhesive sheet sticking apparatus 1 has a laterally long rectangular portion 1a and a protruding portion 1 b. The protruding portion 1b is connected to the center of the rectangular portion 1a and protrudes upward. In the following description, the longitudinal direction of the rectangular portion 1a is referred to as the left-right direction (x direction), and the horizontal direction (y direction) orthogonal thereto is referred to as the front-back direction.

A wafer transfer mechanism 3 is provided on the right side of the rectangular portion 1 a. Two containers 5 containing wafers W are placed in parallel on the lower right side of the rectangular portion 1 a. The wafers W with the protective tape PT bonded to the surface thereof are accommodated in the container 5 in a multi-stage manner with the surface facing downward. A rack recovery unit 6 for recovering the mount MF shown in fig. 8 after the assembly of the wafer W is provided at the left end of the rectangular portion 1 a.

The aligner 7, the holding table 9, and the rack feeding section 12 are provided in this order from the right of the upper side of the rectangular section 1 a. The protruding portion 1b is provided with a joining unit 13, and the joining unit 13 joins an adhesive tape DT (dicing tape) for support across the back surface of the wafer W and the ring frame f.

As shown in fig. 4, the wafer transfer mechanism 3 is provided with a wafer transfer device 16 supported on the right side of a guide rail 15 so as to be movable in a left-right reciprocating manner, and the guide rail 15 is horizontally provided on the upper portion of the rectangular portion 1a in the left-right direction. Further, a rack transport device 17 supported on the guide rail 15 so as to be movable in the left-right direction is provided on the left side of the guide rail 15.

The wafer transfer device 16 is configured to be able to transfer the wafer W taken out from any one of the containers 5 in the right and left directions and in the front and back directions. The wafer transfer device 16 is equipped with a movable table 18 for left and right movement and a movable table 19 for front and rear movement.

The movable right-left movement table 18 is configured to be capable of reciprocating in the right-left direction along the guide rail 15. The movable forward-backward movement table 19 is configured to be capable of reciprocating in the forward-backward direction along a guide rail 20 provided on the movable leftward-rightward movement table 18.

A holding unit 21 for holding the wafer W is provided below the movable stage 19 that moves forward and backward. The holding unit 21 is configured to be capable of reciprocating in the vertical direction (z direction) along a lifting rail 22 extending in the longitudinal direction. The holding unit 21 is rotatable about an axis in the z direction by a rotation shaft, not shown.

A horseshoe-shaped holding arm 23 is provided at the lower portion of the holding unit 21. A plurality of suction pads are provided on the holding surface of the holding arm 23 so as to slightly protrude, and the wafer W is sucked and held by the suction pads. The holding arm 23 is connected to the compressed air device through a flow path formed inside thereof and a connection flow path connected to the base end side of the flow path.

By using the movable structure, the wafer W sucked and held can be moved back and forth, moved right and left, and rotated about the z-axis by the holding arm 23.

The rack transport device 17 includes a movable leftward and rightward movement table 24, a movable forward and rearward movement table 25, a telescopic link mechanism 26 connected to a lower portion of the movable leftward and rightward movement table 24, and an adsorption plate 27 provided at a lower end of the telescopic link mechanism 26. The suction plate 27 sucks and holds the wafer W. A plurality of suction pads 28 for suction-holding the ring frame f are provided around the suction plate 27. Thus, the rack transfer device 17 can suction and hold the ring rack f or the mount frame MF placed and held on the holding base 9 and transfer it up and down, front and rear, left and right. The suction cup 28 is slidably adjustable in the horizontal direction corresponding to the size of the ring frame f.

As shown in fig. 5, 6, and the like, the holding table 9 is a metallic chuck table having the same shape as the wafer W or a size larger than the shape of the wafer W, and is connected to a vacuum device 31 and a pressure device 32 provided outside in communication with each other. The operations of the vacuum device 31 and the pressurizing device 32 are controlled by the control unit 33.

In example 1, the holding base 9 includes an annular projection 9a on the outer peripheral portion, and is hollow as a whole. The projection 9a is configured to be located at a position substantially matching the arrangement of the annular convex portions Ka of the wafer W in plan view, and the projection 9a supports the annular convex portions Ka of the wafer W, whereby the holding table 9 can hold the wafer W without contacting the thin flat concave portions He.

As shown in fig. 5, the holding base 9 is housed in a lower case 29A constituting the chamber 29, and is coupled to one end of a rod 35 penetrating the lower case 29A. The other end of the rod 35 is drivingly connected to a driver 37 including a motor and the like. Therefore, the holding table 9 can be moved up and down inside the chamber 29.

The lower case 29A includes a holder holding portion 38 that surrounds the lower case 29A. The holder holding portion 38 is configured to make the upper surface of the annular holder f flush with the cylindrical top of the lower case 29A when the annular holder f is placed. The cylindrical top of the lower case 29A is preferably subjected to a mold release treatment.

As shown in fig. 3, the holding base 9 is configured to be capable of reciprocating together with the lower case 29A between an initial position and a bonding position along a rail 40 attached in the front-rear direction. The initial position is inside the rectangular portion 1a, and is the position of the holding base 9 indicated by a solid line in fig. 3. In this initial position, the wafer W and the ring frame f are placed on the holding table 9.

The sticking position is inside the protruding portion 1b, and is a position where the holding base 9 is indicated by a broken line in fig. 3. By moving the holding table 9 to the bonding position, the bonding step of bonding the adhesive tape DT to the wafer W placed on the holding table 9 can be performed.

The rack supply unit 12 stores drawer-type boxes in which a predetermined number of ring racks f are stacked and stored.

As shown in fig. 5, the joining unit 13 includes a sheet supply portion 71, a separated sheet collection portion 72, a sheet joining portion 73, a sheet collection portion 74, and the like. The sheet supply section 71 includes a supply winding drum in which a material roll around which an adhesive tape DT for support is wound is loaded. The release sheet S is configured to be released by the release roller 75 while the adhesive tape DT is supplied from the supply reel of the sheet supply portion 71 to the joining position. Further, the supply bobbin provided in the sheet supply portion 71 is linked to an electromagnetic brake in an interlocking manner, and an appropriate rotational resistance is applied thereto. Thus, the tape can be prevented from being excessively discharged from the supply winding bobbin.

The separator recovery section 72 is provided with a recovery winding drum for winding up the separator S peeled off from the adhesive tape DT. The recovery bobbin is driven and controlled by a motor to rotate forward and backward.

The sheet attaching portion 73 is constituted by the chamber 29, the sheet attaching mechanism 81, the sheet cutting mechanism 82, and the like.

The chamber 29 is constituted by a lower case 29A and an upper case 29B. The lower case 29A is disposed so as to surround the holding base 9, and reciprocates in the front-rear direction between the initial position and the adhesion position together with the holding base 9. The upper case 29B is provided on the protruding portion 1B and configured to be able to move up and down.

As shown in fig. 6, the lower case 29A and the upper case 29B are connected in communication with the vacuum device 31 and the pressurizing device 32, respectively, via the flow path 101. Further, an electromagnetic valve 103 is provided in the flow passage 101 on the upper case 29B side. Further, a flow path 109 is connected to each of the two cases 29A and 29B, and the flow path 109 is provided with electromagnetic valves 105 and 107 for opening the atmosphere.

A flow path 111 is connected to the upper case 29B in a communicating manner, and the flow path 111 includes a solenoid valve 110 that adjusts the internal pressure after the temporary pressure reduction by the bleed-off. The opening and closing operations of the electromagnetic valves 103, 105, 107, and 110, the operation of the vacuum device 31, and the operation of the pressurizing device 32 are performed by the control unit 33.

That is, the vacuum device 31 is configured to be capable of independently adjusting the pressure reduction in the space on the lower case 29A side and the pressure reduction in the space on the upper case 29B side. The pressurizing device 32 is configured to be capable of independently pressurizing and adjusting the air pressure in the space on the lower case 29A side and the air pressure in the space on the upper case 29B side.

The sheet sticking mechanism 81 includes a movable table 84, a sticking roller 85, a nip roller 86, and the like. The movable stand 84 horizontally moves in the left-right direction along a guide rail 88 extending in the left-right direction. The pasting roller 85 is pivotally supported by a bracket coupled to a distal end of a cylinder provided on the movable table 84. The pinch roller 86 is disposed on the sheet collecting portion 74 side, and includes a conveying roller 89 driven by a motor and a pinch roller 90 that is raised and lowered by a cylinder.

The sheet cutting mechanism 82 is provided on a lift drive table 91 that moves the upper case 29B up and down, and includes a support shaft 92 extending in the z direction and a boss 93 that rotates about the support shaft 92. The hub 93 has a plurality of support arms 94 extending in the radial direction. A disc-shaped cutter 95 for cutting the adhesive tape DT along the ring frame f is provided at the tip of at least 1 support arm 94 in a manner capable of moving up and down. A pressing roller 96 is provided at the tip of the other support arm 94 so as to be movable up and down.

The sheet collecting section 74 includes a collecting reel for winding the unnecessary adhesive tape DT that has been cut and peeled off. The recovery bobbin is driven and controlled by a motor, not shown, to rotate forward and backward.

As shown in fig. 4, the rack recovery section 6 is equipped with a cassette 41 for loading and recovering the mounting rack MF. The case 41 is provided with: a longitudinal rail 45 coupled and fixed to the assembly frame 43; and a lifting table 49 which is lifted and lowered by the motor 47 along the longitudinal rail 45 by screw feeding. Therefore, the rack collecting unit 6 is configured to mount the mount frame MF on the elevating table 49 and perform pitch feed lowering (japanese: ピッチ feeding り lowering).

< summary of action >

Here, the basic operation of the adhesive sheet sticking apparatus 1 of example 1 will be described. Fig. 7 is a flowchart illustrating a series of steps of attaching the adhesive tape DT to the wafer W using the adhesive sheet attaching apparatus 1.

Step S1 (supply of work)

When the bonding instruction is issued, the ring frame f is conveyed from the frame supply portion 12 to the frame holding portion 38 of the lower case 29A, and the wafer W is conveyed from the container 5 to the holding table 9.

That is, the rack transport device 17 sucks the ring rack f from the rack supply unit 12 and transfers it to the rack holding unit 38. After the suction of the ring frame f is released and the ring frame f is lifted by the frame transfer device 17, the ring frame f is positioned. As an example, the alignment is performed by synchronously moving a plurality of support pins erected so as to surround the rack holding portion 38 in the center direction. The ring frame f stands by while being set on the frame holding portion 38 until the wafer W is conveyed.

The frame transfer device 17 transfers the ring frame f, and the wafer transfer device 16 inserts the holding arm 23 between the wafers W stored in the container 5 in multiple stages. The holding arm 23 sucks and holds the wafer W, sends out the wafer W, and conveys the wafer W to the aligner 7. The aligner 7 adsorbs the center of the wafer W with a chuck protruding from the center thereof. At the same time, the wafer transfer device 16 releases the suction of the wafer W and retreats upward. The aligner 7 performs alignment by a notch or the like while holding the wafer W by the chuck and rotating the wafer W.

After the alignment is completed, the chuck holding the wafer W is protruded from the surface of the aligner 7. The wafer transfer device 16 is moved to this position to suction-hold the wafer W. The suction cup is released from the suction and descends.

The wafer transfer device 16 moves above the holding table 9, and places the wafer W on the holding table 9 with the protective tape PT bonded thereto facing downward. When the holding table 9 holds the wafer W by suction and the ring holder f is held by suction by the holder holding portion 38, the lower case 29A is moved from the initial position to the bonding position on the sheet bonding mechanism 81 side along the rail 40. Fig. 9 shows a state where the wafer W is supplied to the holding table 9 and moved to the bonding position.

Step S2 (adhesive sheet supply)

After the workpiece is supplied by the wafer transfer device 16 or the like, the adhesive tape DT is supplied to the joining unit 13. That is, a predetermined amount of the adhesive tape DT is discharged from the sheet supply portion 71 while the separator sheet S is peeled off. The adhesive tape DT, which is long as a whole, is guided upward from the joining position along a predetermined conveyance path.

Step S3 (formation of Chamber)

After the work and the adhesive tape DT are supplied, the joining roller 85 is lowered as shown in fig. 10. Then, the joining roller 85 joins the adhesive tape DT across the top of the housing 29A and the top of the ring frame f while rolling on the adhesive tape DT. In conjunction with the movement of the joining roller 85, a predetermined amount of the adhesive tape DT is fed from the sheet supplying section 71 while the separator S is peeled off.

After the adhesive tape DT is attached to the ring frame f, the attaching roller 85 is returned to the initial position, and the upper case 29B is lowered. As the upper case 29B is lowered, as shown in fig. 11, the portion of the adhesive tape DT attached to the top of the lower case 29A is sandwiched between the upper case 29B and the lower case 29A to form the chamber 29.

At this time, the adhesive tape DT functions as a sealing material, and the chamber 29 is divided into two spaces by the adhesive tape DT. That is, the adhesive tape DT is divided into a lower space H1 on the lower case 29A side and an upper space H2 on the upper case 29B side. The wafer W positioned in the lower case 29A is close to and opposed to the adhesive tape DT with a predetermined gap therebetween.

Step S4 (the 1 st pasting process)

After the formation of the cavity 29, the 1 st pasting process is started. First, the controller 33 operates the vacuum apparatus 31 to reduce the air pressure in the lower space H1 and the air pressure in the upper space H2 to predetermined values in a state where the electromagnetic valves 105, 107, and 110 shown in fig. 6 are closed. Examples of the predetermined value include 10Pa to 100 Pa. At this time, the opening degree of the solenoid valve 103 is adjusted so that the lower space H1 and the upper space H2 are depressurized at the same speed.

When the air pressure in the lower space H1 and the air pressure in the upper space H2 are reduced to predetermined values, the controller 33 closes the electromagnetic valve 103 and stops the operation of the vacuum apparatus 31. Then, the controller 33 adjusts the opening degrees of the solenoid valves 103, 105, 107, and 110 to perform the relief so that the air pressure in the upper space H2 becomes higher than the air pressure in the lower space H1. By making the air pressure of the upper space H2 higher than the air pressure of the lower space H1, a pressure difference Fa is generated between the two spaces as shown in fig. 12. By generating the pressure difference Fa, the adhesive tape DT is sucked from the central portion toward the lower case 29A side and deformed into a convex shape.

In the present embodiment, control is performed as follows: in a state where the solenoid valves 103 and 107 connected to the lower space H1 are closed, the opening degree of the solenoid valve 110 connected to the upper space H2 is adjusted to be released, and finally, the solenoid valve is fully opened. By this adjustment, the state in which the air pressure of the lower space H1 is reduced to the predetermined value is maintained, and the air pressure of the upper space H2 gradually rises from the predetermined value and returns to the atmospheric pressure, and therefore, the pressure difference Fa is generated.

After the pressure difference Fa is generated, as shown in fig. 13, the actuator 37 is driven to raise the holding table 9. By the deformation of the adhesive tape DT and the rise of the holding table 9 by the pressure difference Fa, the adhesive tape DT radially contacts the back surface of the wafer W from the center portion toward the outer peripheral portion in the lower space H1 from which air is discharged. By this contact, the back surface of the wafer W is covered with the adhesive tape DT.

When the back surface of the wafer W is covered with the adhesive tape DT, the controller 33 fully opens the solenoid valves 103, 105, 107, and 110 to open the upper space H2 and the lower space H1 to the atmosphere. Through this atmospheric opening, the 1 st pasting process is ended. Thus, in the 1 st pasting process, the following operations are performed: the adhesive tape DT is brought into contact with the back surface of the wafer W in a state where the internal space of the chamber 29 is depressurized, whereby the back surface of the wafer W is covered with the adhesive tape DT.

Step S5 (No. 2 pasting Process)

After the adhesive tape DT is attached so as to cover the back surface of the wafer W, the 2 nd attaching process is started. First, the controller 33 controls the actuator 37 to lower the holding base 9 to the initial position. Next, the controller 33 operates the pressurizing device 32 to supply gas to the lower space H1 and the upper space H2 in a state where the electromagnetic valves 105, 107, and 110 shown in fig. 6 are closed, and pressurizes the lower space H1 and the upper space H2 to specific values. Examples of the specific value include 0.3MPa to 0.5 MPa. By the pressurizing operation of the pressurizing device 32, the air pressure of the lower space H1 and the air pressure of the upper space H2 are both higher than the atmospheric pressure.

As shown in fig. 14, the pressing force V1 acts on the adhesive tape DT from the upper space H2 due to the pressurization of the upper space H2. Further, since the entire upper space H2 is pressurized, the pressing force V1 is uniformly applied to the entire adhesive tape DT. Further, since the entire lower space H1 is pressurized, the pressing force V2 is uniformly applied to the downward surface of the wafer W from the lower space H1. That is, the adhesive tape DT is accurately attached to the back surface of the wafer W by the pressing force V1 and the pressing force V2. As a result, since the adhesion between the wafer W and the adhesive tape DT is improved, the adhesive tape DT can be prevented from being peeled off from the back surface of the wafer W with the passage of time.

After a pressing force is applied between the adhesive tape DT and the wafer W for a predetermined time in a state where the lower space H1 and the upper space H2 are pressurized to an atmospheric pressure higher than the atmospheric pressure, the controller 33 stops the operation of the pressurizing device 32. Then, the controller 33 opens the solenoid valves 103, 105, 107, and 110 fully to open the lower space H1 and the upper space H2 to the atmosphere. The controller 33 raises the upper case 29B to open the chamber 29, and also raises the holding table 9 to bring the front surface of the wafer W into contact with the wafer holding surface of the holding table 9.

Step S6 (cutting sheet)

While the steps of step S4 and step S5 are performed in the chamber 29, the adhesive tape DT is cut by operating the sheet cutting mechanism 82. At this time, as shown in fig. 15, the cutter 95 cuts the adhesive tape DT attached to the ring frame f into the shape of the ring frame f, and the pressing roller 96 presses the adhesive tape DT while rolling along the cutter 95 at the sheet cut portion on the ring frame f.

Since the 1 st attaching process of step S4 and the 2 nd attaching process of step S5 have already been completed at the timing of raising the upper case 29B, the pinch roller 90 is raised to release the nipping of the adhesive tape DT. Thereafter, as shown in fig. 16, the nip roller 86 is moved to wind and collect the unnecessary adhesive tape DT after cutting toward the sheet collecting section 74, and a predetermined amount of the adhesive tape DT is discharged from the sheet supplying section 71. Through the steps up to step S6, the mount MF formed by integrating the ring frame f and the wafer W via the adhesive tape DT is formed.

After the unnecessary adhesive tape DT is wound and recovered, the pinch roller 86 and the application roller 85 are returned to the initial position. Then, the holding table 9 moves from the attaching position to the home position while holding the mount MF.

Step S7 (recovery of mounting rack)

When the holding table 9 returns to the initial position, as shown in fig. 17, the suction pads 28 provided in the rack transfer device 17 suck and hold the mount frame MF and separate the mount frame MF from the lower case 29A. The rack transfer device 17 that adsorbs and holds the mount frame MF transfers the mount frame MF to the rack collecting unit 6. The transported mount MF is loaded in the cassette 41.

As described above, the series of operations for attaching the adhesive tape DT to the wafer W is completed. Thereafter, the above process is repeated until the mount MF reaches a predetermined number. In this way, the mount MF in which the adhesive tape DT is adhered to the wafer W in a close contact manner is manufactured by the adhesive sheet adhering apparatus 1. The mount MF in which the adhesive tape DT is attached to the wafer W in the 2 nd attaching process corresponds to the semiconductor device of the present invention.

In example 1, the case where the mount MF in a state where the adhesive tape DT is attached to the wafer W is manufactured using the ring frame f is exemplified, but the process of manufacturing the semiconductor device using the adhesive sheet attaching apparatus 1 is not limited to the case where the ring frame f is used. That is, the adhesive tape DT may be attached to the wafer W by using the adhesive sheet attaching apparatus 1 having the respective configurations in which the operation of the ring frame f is omitted. In this case, the adhesive tape DT is adhered to the wafer W in close contact therewith by performing the steps of example 1. In this case, the wafer W to which the adhesive tape DT is attached after the 2 nd attaching process is completed corresponds to the semiconductor device of the present invention.

< Effect of the structure of embodiment 1 >

With the apparatus of the above example 1, the 1 st and 2 nd pasting processes were performed using the chamber. That is, the adhesive tape DT is bonded to the wafer W in the 1 st bonding step and then the 2 nd bonding step is performed, so that the adhesive tape DT is bonded to the wafer W with more accuracy. With such a configuration, the adhesive tape DT can be accurately attached to the wafer W having the annular convex portions Ka on one surface thereof while avoiding damage to the wafer W.

In the first pasting process of the present invention, the inside of the lower space H1 in which the wafer W is disposed is depressurized in the chamber 29. That is, since the peripheral space of the adhesive tape DT and the peripheral space of the wafer W are depressurized to discharge air, when the adhesive tape DT contacts the wafer W and covers the back surface of the wafer W, gas can be prevented from being trapped between the adhesive tape DT and the wafer W. Therefore, a decrease in the adhesion force due to the entrainment of the gas can be avoided.

In the second bonding step of the present invention, the pressure in the lower space H1 and the pressure in the upper space H2 are increased to be higher than the atmospheric pressure, whereby the adhesive tape DT is bonded to the back surface of the wafer W with high accuracy.

When the pressure difference Fa is generated by depressurizing the inside of the chamber using the vacuum apparatus, the magnitude of the pressure difference Fa generated by depressurization from the atmospheric pressure state is equal to or less than the atmospheric pressure. That is, when the pressure difference Fa is used to press the adhesive tape DT against the wafer W, there is an upper limit to the amount of force with which the adhesive tape DT is pressed against the back surface of the wafer W.

Therefore, in a state where the pressure difference Fa due to the reduced pressure is used to bring the adhesive tape DT into contact with the wafer W, the adhesion between the adhesive tape DT and the wafer W is low. In the conventional structure using the 1 st pressing member, the pressing force can be applied only to a limited portion of the adhesive tape DT. Further, since the magnitude of the pressing force is insufficient, it is difficult to improve the adhesion between the adhesive tape DT and the wafer W.

In contrast, in the present invention, the upper space H2 and the lower space H1 in the chamber 29 are pressurized to a pressure greater than atmospheric pressure using the pressurizing device 32. That is, in the 2 nd bonding process, the pressing forces V1 and V2 sufficiently larger than the pressure difference Fa can be applied to the adhesive tape DT and the wafer W. The pressing forces V1 and V2 act on the entire surface of the adhesive tape DT attached to the wafer W. Therefore, since the adhesion between the adhesive tape DT and the wafer W can be greatly improved by performing the 2 nd attaching process, the adhesive tape DT can be prevented from being peeled off from the wafer W even after a lapse of time after the completion of a series of attaching processes.

Further, by appropriately controlling the pressing device 32 in the 2 nd pasting process, the magnitudes of the pressing force V1 and the pressing force V2 can be adjusted to arbitrary values. Therefore, even when various conditions such as the constituent material of the adhesive material Tb, the size of the wafer W, and the thickness of the annular convex portion Ka are changed, the adhesive tape DT can be reliably attached to the annular convex portion formation surface of the wafer W by appropriately adjusting the magnitudes of the pressing force V1 and the pressing force V2. Further, since the pressing force V1 and the pressing force V2 having appropriate magnitudes are uniformly applied to the entire adhesive tape DT, it is possible to avoid the wafer W from being damaged due to the application of excessive pressing force or variation in pressing force.

[ example 2 ]

Hereinafter, embodiment 2 of the present invention will be described with reference to the drawings. In example 1, a description has been given of an example in which an adhesive tape DT in a long shape is cut into a predetermined shape corresponding to the shape of a workpiece (here, the shape of the wafer W or the ring frame f) after being attached across the back surface of the wafer W and the ring frame f. In embodiment 2, a structure in which an adhesive tape having a predetermined shape corresponding to the shape of a workpiece is attached to the workpiece in advance will be described as an example. Note that the same components as those of the adhesive sheet sticking apparatus 1 of example 1 are denoted by the same reference numerals, and different components will be described in detail.

First, the structure of the adhesive tape DT of example 2 is explained. Fig. 18 (a) is a perspective view showing the back sides of the transport sheet P and the adhesive tape DT, and fig. 18 (b) is a vertical cross-sectional view of the transport sheet P and the adhesive tape DT.

As shown in fig. 18 (a), the adhesive tape DT according to example 2 is held by the long transport sheet P. That is, the adhesive tape DT having a predetermined shape is stuck to and held on one surface of the long transport sheet P at a predetermined pitch. The adhesive tape DT is cut in advance into a predetermined shape corresponding to the shape of the formation surface (back surface in this embodiment) of the annular protrusion Ka of the wafer W. In example 2, the adhesive tape DT was cut into a circular shape in advance.

As shown in fig. 18 (b), the transfer sheet P has a structure in which a non-adhesive base Pa and an adhesive Pb having adhesiveness are laminated. Examples of the material constituting the substrate Pa include polyolefin, polyethylene, and the like. Examples of the material constituting the binder Pb include acrylate copolymers. The base Ta of the adhesive tape DT is bonded to the adhesive material Pb of the transport sheet P, whereby the transport sheet P holds the adhesive tape DT. In the present embodiment, the shape of the adhesive tape DT is a circular shape, but the shape of the adhesive tape DT can be appropriately changed according to the shape of the wafer W.

The basic structure of the adhesive sheet application apparatus 1 of example 2 is the same as that of the apparatus of example 1 shown in fig. 3 to 6. However, the sheet supply section 71 is loaded with a transport sheet P that holds a plurality of adhesive tapes DT molded in advance into a predetermined shape. The sheet cutting mechanism 82 cuts the portion of the conveying sheet P attached to the ring frame f. After the conveyance sheet P is cut by the sheet cutting mechanism 82, the sheet collecting section 74 collects the unnecessary conveyance sheet P remaining around the mounting frame MF.

Action in embodiment 2

Here, the operation of the adhesive sheet sticking apparatus 1 of example 2 will be described. Fig. 19 is a flowchart illustrating a series of steps of attaching the adhesive tape DT to the wafer W using the adhesive sheet attaching apparatus 1 of example 2. The same steps as those of the operation of the adhesive sheet sticking apparatus 1 of example 1 will be described in detail with the explanation simplified.

Step S1 (supply of work)

When the bonding command is issued, the wafer W and the ring frame f are supplied in the same manner as in example 1. That is, the ring frames f stored in the frame supply unit 12 are transferred to the frame holding unit 38 by the frame transfer device 17. The wafers W stored in the container 5 are transferred to the holding table 9 by the wafer transfer device 16 through the aligner 7. After the ring frame f and the wafer W are transferred, the lower case 29A is moved from the initial position to the attachment position along the rail 40. Fig. 20 shows a state where the holding table 9 is moved to the pasting position.

Step S2 (adhesive sheet supply)

After the workpiece is supplied by the wafer transfer device 16 or the like, the adhesive tape DT is supplied to the joining unit 13. That is, a predetermined amount of the adhesive tape DT is released from the sheet supply portion 71 together with the transfer sheet P while peeling the separator S. The conveying sheet P, which is long as a whole, is guided upward of the joining position along a predetermined conveying path. At this time, as shown in fig. 21, the adhesive tape DT held by the transport sheet P is positioned above the wafer W placed on the holding table 9.

Step S3 (formation of Chamber)

After the adhesive tape DT is fed above the holding table 9, a chamber 29 is formed. That is, as shown in fig. 22, the application roller 85 is lowered. Then, the pasting roller 85 pastes the conveying sheet P so as to straddle the top of the lower case 29A and the top of the ring frame f while rolling on the conveying sheet P. In conjunction with the movement of the joining roller 85, a predetermined amount of the adhesive tape DT is fed out from the sheet supply portion 71 together with the transfer sheet P while the separator sheet S is peeled off.

After the adhesive tape DT is attached to the ring frame f, the attaching roller 85 is returned to the initial position, and the upper case 29B is lowered. As the upper case 29B is lowered, as shown in fig. 23, the portion of the conveying sheet P attached to the top of the lower case 29A is sandwiched between the upper case 29B and the lower case 29A to form the chamber 29. At this time, the conveying sheet P functions as a sealing material, and the chamber 29 is divided into a lower space H1 and an upper space H2 by the adhesive tape DT.

Step S4 (the 1 st pasting process)

After the formation of the cavity 29, the 1 st pasting process is started in the same manner as in example 1. The controller 33 operates the vacuum device 31 to reduce the pressure in the lower space H1 and the pressure in the upper space H2 to predetermined values, and further, to make the pressure in the upper space H2 higher than the pressure in the lower space H1. By controlling the air pressure, a pressure difference Fa is generated between the lower space H1 and the upper space H2. As shown in fig. 24, the adhesive tape DT is radially brought into contact with the back surface of the wafer W from the center portion toward the outer peripheral portion by the rise of the holding table 9 and the deformation of the adhesive tape DT by the pressure difference Fa, and the back surface of the wafer W is covered with the adhesive tape DT.

Step S5 (No. 2 pasting Process)

After the back surface of the wafer W is covered with the adhesive tape DT by using the vacuum apparatus 31, the 2 nd attaching process is performed in the same manner as in example 1. First, the controller 33 lowers the holding base 9, operates the pressurizing device 32, and supplies gas to the lower space H1 and the upper space H2 to pressurize the lower space H1 and the upper space H2 to specific values. By the pressurizing operation of the pressurizing device 32, the air pressure of the lower space H1 and the air pressure of the upper space H2 are both higher than the atmospheric pressure.

As shown in fig. 25, the pressing force V1 acts on the adhesive tape DT from the upper space H2 due to the pressurization of the upper space H2. In addition, since the entire lower space H1 is pressurized, the pressing force V2 acts on the downward surface of the wafer W from the lower space H1. That is, the pressure-sensitive adhesive tape DT is accurately stuck to the back surface of the wafer W by the pressing force V1 and the pressing force V2, which are sufficiently large forces, and the adhesion between the wafer W and the pressure-sensitive adhesive tape DT is improved.

After a pressing force is applied between the adhesive tape DT and the wafer W for a predetermined time in a state where the lower space H1 and the upper space H2 are pressurized to an atmospheric pressure higher than the atmospheric pressure, the controller 33 stops the operation of the pressurizing device 32. Then, the controller 33 opens the solenoid valves 103, 105, 107, and 110 fully to open the lower space H1 and the upper space H2 to the atmosphere. The controller 33 raises the upper case 29B to open the chamber 29, and also raises the holding table 9 to bring the front surface of the wafer W into contact with the wafer holding surface of the holding table 9.

Step S6 (cutting of conveying sheet)

While the steps of step S4 and step S5 are performed in chamber 29, sheet cutting mechanism 82 is operated. In example 2, the process is different from that of example 1 in that the sheet cutting mechanism 82 cuts the conveying sheet P. That is, as shown in fig. 26, the cutter 95 cuts the transport sheet P attached to the ring frame f into the shape of the ring frame f, and the pressing roller 96 presses the transport sheet P while rolling along the cutter 95 at the sheet cutting portion on the ring frame f.

After the conveying sheet P is cut into a circular shape, the upper case 29B is raised. Since the processes of step S4 and step S5 have been completed at the timing of raising the upper case 29B, the pinch roller 90 is raised to release the nipping of the adhesive tape DT. Thereafter, the nip roller 86 is moved to wind and collect the cut unnecessary transport sheet P into the sheet collection unit 74, and the predetermined amount of the adhesive tape DT is discharged from the sheet supply unit 71 together with the transport sheet P.

Through the respective processes up to step S6, the mount MF is formed. In the mount frame MF of example 2, the ring frame f and the wafer W are integrated via the adhesive tape DT and the transport sheet P. After the unnecessary conveyance sheet P is taken up and collected, the grip roller 86 and the application roller 85 are returned to the initial positions. Then, the holding table 9 moves from the attaching position to the home position while holding the mount MF.

Step S7 (recovery of mounting rack)

When the holding table 9 is returned to the initial position, the suction pads 28 provided in the rack conveyance device 17 suck and hold the mount frame MF and separate the mount frame MF from the lower case 29A, as in embodiment 1. The rack transfer device 17 that adsorbs and holds the mount frame MF transfers the mount frame MF to the rack collecting unit 6. The transported mount MF is loaded in the cassette 41.

As described above, the series of operations for attaching the adhesive tape DT to the wafer W is completed. Thereafter, the above process is repeated until the mount MF reaches a predetermined number. By using the adhesive sheet sticking apparatus 1 of example 2, the same effects as those of example 1 can be obtained even in the case of using the adhesive tape DT cut in advance into a predetermined shape. That is, when the adhesive tape DT is attached to the annular convex portion forming surface of the wafer W having the annular convex portion, the adhesive tape DT can be accurately attached to the wafer W while avoiding damage to the wafer W.

In addition, all the aspects of the embodiments disclosed herein are illustrative and not restrictive. The scope of the present invention is defined not by the description of the above embodiments but by the claims, and includes all modifications (variations) within the meaning and scope equivalent to the claims. As an example, the present invention can be modified as described below.

(1) In step S4 of each embodiment, after the air pressure of the lower space H1 and the air pressure of the upper space H2 are depressurized to predetermined values, the air pressure of the upper space H2 is returned to the atmospheric pressure, thereby generating the pressure difference Fa, but the adjustment of the air pressure in step S4 is not limited thereto. That is, after the air pressure in the lower space H1 and the air pressure in the upper space H2 are reduced to predetermined values, the air pressure in the lower space H1 may be maintained at the predetermined values, and the opening degree of the electromagnetic valve 105 may be appropriately adjusted to perform the relief.

In this case, the pressure in the upper control space H2 increases from a predetermined value to a predetermined value lower than the atmospheric pressure, and the pressure difference Fa is generated by this control. After the annular convex portion forming surface of the wafer W is covered with the adhesive tape DT by the pressure difference Fa, the controller 33 opens the solenoid valves 103, 105, 107, and 110 fully to open the upper space H2 and the lower space H1 to the atmosphere. Through this atmospheric opening, the 1 st pasting process is ended.

In the structure in which the pressure difference Fa is generated by returning the atmospheric pressure in the upper space H2 to the atmospheric pressure as in each of the embodiments, the pressure difference Fa can be further increased, and therefore, the process of deforming the adhesive tape DT and covering the annular protrusion formation surface of the wafer W with the adhesive tape DT can be completed more quickly. On the other hand, in the configuration in which the pressure in the upper space H2 is adjusted to a specific value higher than the pressure in the lower space H1 and lower than the atmospheric pressure to generate the pressure difference Fa as in the modification (2), the deformation speed of the adhesive tape DT is suppressed to be low. Therefore, the adhesive tape DT can be prevented from covering the annular projection forming surface of the wafer W too early while the air discharge from the lower space H1 is not completed, and therefore, a gap can be prevented from being generated between the adhesive tape DT and the wafer W.

(2) In step S5 of each embodiment, the pressurizing device 32 pressurizes the insides of both the lower space H1 and the upper space H2, but is not limited thereto. That is, the pressure device 32 may apply pressure to only the upper space H2 to an air pressure higher than the atmospheric pressure, and the pressure force V1 may be used to attach the adhesive tape DT more accurately.

As a further modification of the structure for pressurizing only the upper space H2, the following structure may be adopted: the adhesive tape DT is attached by pressurizing the inside of the upper space H2 to an atmospheric pressure higher than the atmospheric pressure while maintaining the state in which the inside of the lower space H1 is depressurized to an atmospheric pressure lower than the atmospheric pressure. In this configuration, after the 1 st pasting process by the pressure difference Fa is performed in step S4, the electromagnetic valve 105 connected to the upper space H2 is opened while maintaining the state in which the air pressure of the lower space H1 is reduced to a predetermined value, and only the upper space H2 is opened to the atmosphere. Then, in step S5, the pressurizing device 32 is operated to pressurize the interior of the upper space H2 to a pressure higher than the atmospheric pressure.

In this modification, in step S5, the 2 nd attaching process is performed by pressurizing the inside of the upper space H2 in a state where the holding base 9 is raised and the holding base 9 is brought into contact with the back surface of the wafer W. By generating the pressing force V1 by pressurizing the upper space H2 in a state where the wafer W is held by the holding table 9, the pressing force V1 can be uniformly applied to the entire surface of the adhesive tape DT and the entire surface of the wafer W even in a state where the lower space H1 is depressurized to a pressure lower than the atmospheric pressure.

(3) In step S4 of each example, the pressure difference Fa is generated inside the chamber 29 by using the vacuum apparatus 31, and the adhesive tape DT is deformed into a convex shape and brought into contact with the annular convex portion forming surface of the wafer W. That is, as shown in fig. 28, the pressing member 141 may be provided inside the upper case 29B.

The pressing member 141 has a convex bottom surface (e.g., a hemispherical shape), and the pressing member 141 is disposed above the adhesive tape DT. Therefore, by lowering the pressing member 141, the bottom surface of the pressing member 141 having a convex shape presses the adhesive tape DT, and the adhesive tape DT can be deformed into a convex shape and brought into contact with the wafer W. In this case, a structure necessary for generating the pressure difference Fa can be omitted. In addition, as another structure for deforming the adhesive tape DT in a convex shape, a structure in which the adhesive tape DT is pressed from above using a roller or the like is also exemplified.

(4) In each of the embodiments, the description has been given taking the structure in which the adhesive tape DT for support is attached to the wafer W as an example, but the adhesive tape DT attached to the wafer W is not limited to this. The structure of each embodiment can be applied to a structure in which a sheet-like adhesive material, for example, an adhesive tape for circuit protection is attached.

(5) In each of the embodiments, the wafer W and the ring frame f are exemplified as the workpiece to be bonded with the adhesive sheet, but the workpiece is not limited thereto. As an example, the ring frame f may be omitted and the adhesive sheet may be attached only to the wafer W. In addition, various semiconductor members such as a substrate and a panel can be applied as a workpiece to the structure of this embodiment. The shape of the workpiece may be a rectangular shape, a polygonal shape, a substantially circular shape, or the like, in addition to a circular shape.

(6) In each embodiment, the adhesive tape DT is attached to the wafer W by moving the holding table 9 up and down at predetermined timing, but the movement of the holding table 9 up and down can be changed as appropriate. For example, the pressurizing process of step S5 is not limited to the configuration in which the holding base 9 is lowered and then performed, and the pressurizing process may be performed while maintaining the raised state.

(7) In each embodiment, the holder holding portion 38 is disposed outside the lower case 29A, but the holder holding portion 38 may be disposed inside the lower case 29A. In this case, the processes after step S4 are performed in a state where the ring frame f and the wafer W are housed in the chamber 29.

(8) In example 2, the adhesive tape DT is molded in advance into a predetermined shape corresponding to the shape of the annular convex portion forming surface of the wafer W, but is not limited thereto. That is, the sheet supply section 71 may be loaded with an elongated adhesive tape DT to which an elongated transport sheet P is added. The structure of the long adhesive tape DT to which the long transport sheet P is added is shown in fig. 29 (a). In this case, the adhesive sheet sticking apparatus 1 includes a sheet cutting apparatus 201 upstream of the chamber 29, and the sheet cutting apparatus 201 forms the long adhesive tape DT into a predetermined shape.

The structure of the sheet cutting apparatus 201 is shown in fig. 29 (b). The sheet cutting device 201 includes a support base 203, a cutter 205, and a psa sheet collecting section 207. The adhesive tape DT fed out from the tape supply unit 71 and the transport sheet P are reversed by a reversing device, not shown, and the adhesive tape DT is supplied to the sheet cutting device 201 in such a state as to be positioned above the transport sheet P.

The support table 203 is disposed to horizontally receive the long adhesive tape DT fed and paid out from the sheet feeding portion 71 in the direction L and the lower conveyance sheet P of the conveyance sheets P. The cutter 205 is disposed above the support table 203 and can be moved up and down by a movable table, not shown. As an example of the cutter 205, an annular thomson knife can be used.

By lowering the cutter 205, the layer of the adhesive tape DT in the adhesive tape DT and the transport sheet P is cut off in the shape of the annular locus K. The structure of cutting the adhesive tape DT with the cutter 205 is not limited to this, and another example thereof is a structure of cutting the adhesive tape DT in a circular shape by moving the cutter 205 in a knife shape along a circular trajectory.

The adhesive sheet recovery section 207 recovers the unnecessary adhesive tape DTn remaining around the adhesive tape DT cut into a circular shape. The adhesive tape DTn of the unnecessary portion is peeled off from the conveying sheet P immediately behind the conveying roller 208. The peeled adhesive tape DTn is guided to the recovery bobbin 210 by the guide roller 209. The recovery winding bobbin 210 winds and recovers the adhesive tape DTn peeled off from the transport sheet P. Therefore, the adhesive tape DT formed into a circular shape by the cutter 205 is left on the transport sheet P by the sheet cutting device 201.

The adhesive tape DT cut into a circular shape is guided to the chamber 29 together with the transport sheet P. The adhesive tape DT and the transport sheet P are reversed again by a reversing device, not shown, downstream of the sheet cutting device 201, and the adhesive tape DT is guided to the chamber 29 in a state of being positioned below the transport sheet P.

(9) In each embodiment, as shown in fig. 30 (a), the chamber 29 may be provided with a sheet-like elastic body Ds. The following describes a modification of the present embodiment by illustrating the structure of embodiment 2.

The elastic body Ds is disposed inside the upper case 29B and configured to contact the inner diameter of the upper case 29B. Further, the lower surface of the elastic body Ds and the cylindrical bottom portion of the upper case 29B are configured to be flush. Therefore, when the chamber 29 is formed by the lower case 29A and the upper case 29B sandwiching the transport sheet P, the elastic body Ds abuts against the transport sheet P. Specifically, the elastic body Ds abuts on a surface of the transport sheet P on the side opposite to the surface holding the adhesive tape DT (upper surface side in the drawing). By disposing the elastic body Ds in contact with the inner diameter of the lower case 29A, the elastic body Ds is not sandwiched when the chamber 29 is formed, and therefore, the sealability of the chamber 29 can be prevented from being lowered by the elastic body Ds. Examples of the material constituting the elastic body Ds include rubber, an elastic body, and a gel-like polymer material.

By providing the elastic body Ds in the chamber 29, the bending ratio of the adhesive tape DT can be made more uniform when the adhesive tape DT is deformed into a convex shape in step S4. Here, the effect of the structure including the elastic body Ds will be described. As an example, when the adhesive tape DT is made of a hard material, the bending ratio of the adhesive tape DT tends to be uneven as shown in fig. 30 (b).

That is, in the region P1 in the transport sheet P where the adhesive tape DT is held by the transport sheet P, the bending ratio of the transport sheet P by the pressure difference Fa is small because the adhesive tape DT is hard. On the other hand, in the region P2 of the transport sheet P where the adhesive tape DT is not held by the transport sheet P, the bending ratio of the transport sheet P due to the pressure difference Fa is relatively large. That is, the region P2 is more easily deformed by the pressure difference Fa, and the bending ratio of the conveying sheet P in the region P1 is further reduced.

Further, the tape DT has a large curvature on the side close to the region P2, and the central portion of the tape DT has a small curvature. In this way, the bending ratio is not uniform in each of the adhesive tape DT and the transport sheet P due to the pressure difference Fa. As a result, the adhesive tape DT attached to the wafer W has poor adhesion to the wafer W.

On the other hand, when the elastic body Ds is provided, as shown in fig. 30 (c), the entire elastic body Ds is uniformly deformed in a convex shape by the pressure difference Fa. Therefore, the bending ratio of the conveying sheet P in the region P1 is increased and the difference between the bending ratios in the region P2 is reduced, and therefore, the bending ratio of the conveying sheet P and the bending ratio of the adhesive tape DT are uniform as a whole. That is, the adhesive tape DT is easily deformed according to the shape of the annular convex portion forming surface of the wafer W, and therefore, the adhesion between the adhesive tape DT and the wafer W can be further improved.

(10) In each embodiment, the adhesive tape DT may be heated. As an example of the structure for heating the adhesive tape DT, as shown in fig. 31 (a), the sheet joining mechanism 81 includes a heating mechanism 120 inside the upper case 29B. The heating mechanism 120 includes a cylinder 121 and a heating member 123. The cylinder 121 is coupled to an upper portion of the heating member 123, and the heating member 123 can be moved up and down inside the chamber 29 by the operation of the cylinder 121. The heating member 123 may not be configured to be movable in the up-and-down direction if it can heat the adhesive tape DT.

A heater 125 for heating the adhesive tape DT is embedded in the heating member 123. The heating temperature by the heater 125 is adjusted to a temperature at which the adhesive tape DT becomes soft. An example of the heating temperature is about 50 to 70 ℃. The shape of the bottom surface of the heating member 123 may be changed according to the shape of the wafer W. As an example, the heating member 123 is formed in a cylindrical shape as a whole.

Further, it is preferable that the upper space H2 is heated in advance using the heating mechanism 120 before starting the step S4. That is, the controller 33 operates the heater 125 to heat the heating member 123 to a predetermined temperature. By heating the heating member 123, the upper space H2 is heated by the heat conduction effect, and the adhesive tape DT is further heated.

Since the adhesive tape DT is heated and becomes flexible, the deformability of the adhesive tape DT by the pressure difference Fa is improved. That is, when the wafer W is covered with the adhesive tape DT, the following property of the adhesive tape DT with respect to the wafer W can be further improved. As shown in fig. 31 (b), the heating member 123 may be lowered to approach or come into contact with the adhesive tape DT, and the adhesive tape DT may be directly heated by the heating member 123.

(11) In the embodiment, the heating mechanism 120 is disposed on the upper space H2 side in the chamber 29 and heats the upper space H2, but the present invention is not limited thereto. That is, the heating mechanism 120 may be configured to heat the lower space H1. As an example, the following structure can be given: the heater 125 is disposed inside the holding table 9, and the lower space H1 is heated by the heater 125 to heat the adhesive tape DT. Further, the heating mechanism 120 may be configured to heat both the upper space H2 and the lower space H1.