阅读说明：本技术 对准装置、半导体晶圆处理装置及对准方法 (Alignment apparatus, semiconductor wafer processing apparatus, and alignment method ) 是由 渡边启晖 酒井哲也 鬼海大司 于 2019-02-26 设计创作，主要内容包括：一种对准晶圆的凹口部分的对准装置,其包括保持晶圆的载置台、移动载置台的移动单元、检测凹口部分的周向位置的凹口部分检测单元、以及通过移动单元控制载置台的位置的控制器。载置台包括载置台主体部分和附接至载置台主体部分中的开口以保持晶圆的衬垫构件。衬垫构件包括：主体部分,其附接至所述开口,并且在其中央部分具有通孔；第一环形部分,其位于衬垫构件的端部侧以抵靠晶圆；以及第一凸缘部分,其与第一环形部分和主体部分一体地设置,并且朝向主体部分的外侧延伸。(An alignment apparatus to align a notch portion of a wafer includes a stage to hold the wafer, a moving unit to move the stage, a notch portion detecting unit to detect a circumferential position of the notch portion, and a controller to control the position of the stage by the moving unit. The table includes a table body portion and a cushion member attached to an opening in the table body portion to hold the wafer. The cushion member includes: a body portion attached to the opening and having a through hole at a central portion thereof; a first annular portion located on an end side of the cushion member to abut against the wafer; and a first flange portion provided integrally with the first ring portion and the body portion and extending toward an outer side of the body portion.)

1. An alignment apparatus that aligns a notch portion at an edge of a wafer to a predetermined position in a circumferential direction, the alignment apparatus comprising:

a plurality of tables on which the wafer is placed and which are arranged side by side in a horizontal plane;

a plurality of moving units configured to rotate the tables accordingly, and configured to move the tables in a predetermined direction in a horizontal plane;

a plurality of notch portion detection units corresponding to the stage and configured to detect circumferential positions of notch portions at edges of the wafer mounted on the stage, respectively; and

a controller configured to detect circumferential positions of the wafers by the notch portion detection units, respectively, and configured to control positions of the stage in a horizontal plane by the moving unit based on information on the detected circumferential positions to prevent interference between the wafers when the wafers mounted on the stage are rotated by the moving unit, respectively, so that the circumferential positions are aligned at positions in a predetermined circumferential direction, respectively,

wherein each table of the plurality of tables includes a table body portion, and a backing member attached to an opening in the table body portion and configured to hold a wafer,

wherein the cushion member includes:

a body portion attached to the opening and including a through-hole in a middle portion thereof;

a first annular portion located on an end side of the cushion member and configured to abut against a wafer; and

a first flange portion provided integrally with the first ring portion and the body portion and extending toward an outer side of the body portion.

2. The alignment device as set forth in claim 1,

wherein the cushion member further comprises:

a second annular portion that is located on a rear end side of the cushion member and has the same shape as the first annular portion; and

a second flange portion provided integrally with the second annular portion and the main body portion and juxtaposed in the table main body portion.

3. The alignment device as set forth in claim 1,

wherein the cushion member further comprises:

a third flange portion provided integrally with the main body portion on a rear end portion side of the cushion member and extending toward an outer side of the main body portion.

4. The alignment device according to any one of claims 1 to 3,

wherein the table main body portion includes a passage therein, one end portion of the passage is connected to the opening, and the other end portion of the passage is connected to an air intake and exhaust unit.

5. The alignment device according to any one of claims 1 to 3,

wherein the body portion is a cylindrical member, and

wherein the first flange portion includes a tapered portion configured to expand in diameter from the first annular portion side toward the body portion side.

6. The alignment device as set forth in claim 2,

wherein the body portion is a cylindrical member, and

wherein the second flange portion includes a tapered portion configured to expand in diameter from the second annular portion side toward the body portion side.

7. The alignment device as set forth in claim 2,

wherein the cushion member is attached to the table body portion by clamping the table body portion by means of the first and second flange portions.

8. The alignment device as set forth in claim 3,

wherein the cushion member is attached to the table body portion by clamping the table body portion by means of the first and third flange portions.

9. The alignment device according to any one of claims 1 to 3,

wherein the cushion member is made of a conductive resin obtained by dispersing conductive fine particles in a resin composition.

10. The alignment device according to any one of claims 1 to 3,

wherein an outer diameter of the first annular portion is smaller than an outer diameter of the body portion.

11. The alignment device of any of claims 1 to 3, further comprising:

an ID reading unit located at an intermediate position between the tables,

wherein the controller is configured to rotate the wafers mounted on the stage by the moving unit, to detect circumferential positions of notch portions in the wafers by the notch portion detecting unit, and to read the IDs attached to peripheral portions of the wafers by the ID reading unit while controlling the positions of the stage in a horizontal plane by the moving unit to prevent interference between the wafers.

12. The alignment device according to any one of claims 1 to 3,

wherein the controller includes an interlocking unit configured to control a position of the stage in a horizontal plane by the moving unit to prevent interference between the wafers loaded on the stage when the wafers are rotated by the moving unit.

13. The alignment device as set forth in claim 11,

wherein the controller includes an interlock unit configured to control to read an ID of one of the wafers, configured to control a position of the stage in a horizontal plane via the moving unit, and configured to perform control to read an ID of another wafer so as to prevent interference between the wafers when the ID reading unit reads the IDs of the wafers mounted on the stage.

14. The alignment device as set forth in claim 11,

wherein the controller includes an interlocking unit configured to control a position of the stage in a horizontal plane by the moving unit, and to control so as to alternately read the IDs of the wafers with a time difference, thereby preventing interference between the wafers when the ID reading unit reads the IDs of the wafers mounted on the stage accordingly.

15. A semiconductor wafer processing apparatus comprising the alignment apparatus according to any one of claims 1 to 3, the semiconductor wafer processing apparatus further comprising:

a conveying device is arranged on the conveying device,

wherein the transfer device is configured to load wafers onto the plurality of tables of the alignment device arranged side by side in a horizontal plane, respectively, and to take wafers out of the tables, respectively.

16. The semiconductor wafer processing apparatus of claim 15,

wherein the transfer device is a two-arm robot.

17. An alignment method for aligning a wafer using the alignment device according to any one of claims 1 to 14, the alignment method comprising:

loading the plurality of wafers into the plurality of tables arranged side by side in a horizontal plane, respectively;

holding the wafer by pad members respectively attached to the plurality of tables;

detecting a notch portion of a wafer on the stage while rotating the stage;

aligning the detected notch portion of the wafer to a position in a predetermined circumferential direction by further rotating the stage;

performing a first control of a position of the stage to prevent interference between wafers when aligning the wafers; and

unloading the wafers on the plurality of tables from the plurality of alignment devices, respectively, to bring the wafers outside the alignment devices by an external unloading device.

18. The method of aligning according to claim 17,

wherein (i) wafer loading, wafer unloading, or notch portion inspection in an area of one of the tables, and (ii) wafer loading, wafer unloading, or notch portion inspection in an area of another one of the tables are configured to be performed continuously or partially overlapped.

19. The alignment method according to claim 17 or 18,

and when the notch part detection determines that the position offset of the wafer relative to the carrying table exceeds a specified range, taking out the wafer from the alignment device.

20. The alignment method according to claim 17 or 18, further comprising:

reading, by an ID reading unit at an intermediate position between the plurality of stages, IDs respectively attached to the plurality of wafers.

21. The alignment method of claim 20, further comprising:

the position of the mounting table is controlled for the second time to prevent interference between wafers in ID reading.

22. The alignment method of claim 20, further comprising:

a second control to restrict movement of another one of the wafers to the ID reading unit during reading of the ID of the one of the wafers, and to allow the another one of the wafers to move to the ID reading unit after reading of the ID of the one of the wafers, thereby preventing interference between the wafers in the ID reading.

23. The method of alignment according to claim 20,

wherein the stage in a horizontal plane is moved to a take-out position to take out the wafer after ID reading to perform the alignment.

Technical Field

The present invention relates to an alignment apparatus for positioning a wafer. The invention also relates to a semiconductor wafer processing device comprising the alignment device and an alignment method using the alignment device.

Background

In general, a series of processing steps such as a pattern forming step of applying a photoresist to a semiconductor wafer (hereinafter referred to as a wafer) serving as a substrate to be processed and firing a pattern of a circuit, a film forming step of forming various films, and an etching step of removing unnecessary portions or films on the wafer are performed in a manufacturing process of a semiconductor device.

When the predetermined process is performed on the wafer, it is preferable to perform the predetermined process in a state where the crystal orientation of the wafer is maintained in a predetermined direction, which is apparent in the pattern forming step and other steps. For this reason, an alignment apparatus is generally used in which a notch cut in a U-shape or a V-shape is provided at an edge of a wafer, a circumferential position of the notch of the wafer to be processed is detected by a notch detection sensor, and the notch is positioned (i.e., aligned) to be aligned with a predetermined circumferential position based on detected data. In this way, a plurality of wafers in a state where the orientation of the wafers is maintained in a predetermined direction are transferred to the next process step by the robot.

Such alignment devices can be used by mounting them on special devices called sorters. The sorter (sorting device) includes, for example, two load ports, one or two wafer transfer robots, and one or two alignment devices. Each load port includes a lid opening and closing mechanism that opens and closes a lid of a container (e.g., FOUP) storing a plurality of wafers in a state in which inflow of external air is prevented. Here, one of the load ports includes a FOUP storing a plurality of wafers having random orientations. The other load port includes an empty FOUP. The robot extracts one (or two) of a plurality of wafers having random orientations from a FOUP of one load port and transfers the extracted wafers to the alignment device. The alignment device aligns the orientation of the wafer in a predetermined direction, and then the robot takes the wafer out of the alignment device and transfers the wafer to a FOUP of another load port in a standby state. By repeating this operation, wafers in a FOUP at one load port are transferred into a FOUP at the other load port in a state where the orientations of the wafers are aligned in a predetermined direction.

Currently, sorters may include two alignment devices. However, in this case, the footprint of the sorter is increased by simply adding one alignment device and by arranging two alignment devices side by side, which reduces the throughput of the sorter.

Further, in the alignment apparatus, in addition to precisely aligning the orientation of the wafer, the ID embedded on the wafer can be read.

Instead of installing two alignment devices in the sorter, it is conceivable to install one alignment device (hereinafter, referred to as W wafer alignment device) capable of aligning two wafers.

The alignment apparatus includes two mounting stages, two notch detection units, and two ID reading units on one body thereof. This makes the alignment device generally complicated and its cost increases.

JP-B-5452166 discloses an alignment device in the form of an example of a W wafer alignment device. In the alignment apparatus described in JP-B-5452166, a robot simultaneously transfers two wafers to the alignment apparatus in a state where the two wafers are stacked in a vertical direction, and the two wafers are simultaneously aligned in the alignment apparatus and simultaneously taken out of the alignment apparatus by the robot, so that the alignment time is short.

Disclosure of Invention

Problems to be solved by the invention

However, in the alignment apparatus described in JP-B-5452166, two wafers are aligned side by side in the horizontal direction. Therefore, after the robot transfers the two wafers to the alignment device and before the robot takes out the two wafers from the alignment device, it is necessary to change the holding postures of the two wafers. As a result, the throughput of the alignment apparatus is reduced.

Further, the alignment device described in JP-B-5452166 requires adjustment of the position of the robot-side arm when the robot takes out a wafer from the alignment device. That is, the robot takes out the wafer by: by finely adjusting its arm for each wafer based on information of the wafer center detected by the alignment device, the center of the wafer loading portion (hand) of the arm of the robot coincides with the wafer center on the alignment device. Therefore, there may be a time loss of fine adjustment and a problem that the throughput of the alignment apparatus is lowered.

Further, the alignment apparatus described in JP-B-5452166 does not clearly describe a unit for reading an ID embedded on a wafer. If the ID reading unit is simply equipped as one wafer-one ID reading unit, the size of the entire alignment apparatus increases, and the cost of the alignment apparatus increases because the ID reading apparatus is expensive.

JP-B-4720790 discloses an alignment apparatus as another example of a W wafer alignment apparatus. The alignment apparatus described in JP-B-4720790 is the same as that of JP-B-5452166 in that two wafers can be aligned in one alignment apparatus and simultaneously transferred by one wafer transfer robot. However, the aligning apparatus described in JP-B-4720790 differs from that of JP-B-5452166 in the following points.

That is, the alignment apparatus described in JP-B-4720790 includes a three-layer coaxial grip portion (corresponding to a stage) on which a wafer is loaded and held. The two wafers held by any two grip portions are not rotated individually, but are rotated together with each other to detect the notch position of each of the wafers. However, the alignment of the two wafers is not performed simultaneously based on the detected notch position information, but is performed separately. First, the first wafer is taken out after alignment, and the third wafer is placed on and held on the grip portion of the remaining layer. Next, the second wafer and the third wafer are rotated together to align the second wafer. Hereinafter, a description of detailed operations is omitted. However, in this alignment apparatus, two wafers held by any two grip portions are rotated together to detect the notch positions of the wafers, but the wafers are not aligned at the same time.

Since the alignment of the two wafers is not performed simultaneously, there is still room for improving the throughput of the alignment apparatus described in JP-B-4720790.

Further, in the aligning apparatus described in JP-B-4720790, there may be a problem that: since the ID reading device of the wafer is different for each wafer, the size and cost of the alignment device increase.

Further, it is known that a stage on an alignment apparatus, on which a wafer is mounted, is formed by directly cutting a member constituting the stage, or by attaching a packing molded from an elastic material such as natural rubber or synthetic rubber to the stage.

As an example of using such a pad, JP-Y-2586261 discloses an adsorption pad including an attachment portion, a root portion expanding to the attachment portion, and a skirt portion integrally connected to the root portion. The root portion has a generally circular cross-section and an outer periphery thereof is progressively enlarged in diameter to join the skirt portions. The skirt portion has a substantially circular cross-section greater than the cross-section of the root portion. The base portion from the starting point to the ending point of the skirt portion is integral with the skirt portion and becomes gradually thinner from the starting point to the ending point of the skirt portion. The inner bottom surface of the skirt portion is provided with a through hole reaching the opening from the bottom surface of the skirt portion in a substantially middle portion of the surface contacting the workpiece.

JP-B-5379589 discloses a vacuum suction pad attached to a first attachment hole in a transfer arm of a substrate transfer device and connected to a vacuum suction path of the transfer arm to vacuum-suck a substrate to the transfer arm.

However, when a wafer is held by a mounting table using the above-described pad, there may be the following problems.

In the suction pad of JP-Y-2586261, the portion that contacts the workpiece is reduced by thickening the base portion of the skirt portion. However, in recent years, the contact area between the suction pad and the workpiece tends to become small, so that a corresponding solution is required.

The vacuum adsorption pad of JP-B-5379589 is attached to the attachment hole of the transfer arm via a sealing member so that airtightness is ensured by the sealing member. Therefore, when the vacuum adsorption pad is replaced, the sealing member also needs to be replaced, so that the replacement work of the vacuum adsorption pad becomes complicated.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an alignment apparatus capable of stably holding a wafer mounted on a stage of the alignment apparatus and facilitating replacement work such as attaching and detaching a pad member.

Another object of the present invention is to provide an alignment apparatus capable of simultaneously aligning a plurality of wafers using one alignment apparatus and reading IDs of the plurality of wafers. Another object of the present invention is to provide an alignment apparatus which is compact and inexpensive with high throughput and can perform alignment and ID reading safely without interference between adjacent wafers. Another object of the present invention is to provide a semiconductor wafer processing apparatus including such an alignment apparatus and an alignment method using the same.

Means for solving the problems

In order to achieve the above object, the present invention provides an alignment apparatus for aligning a notch portion at an edge of a wafer to a predetermined position in a circumferential direction, the alignment apparatus comprising:

a plurality of tables arranged side by side in a horizontal plane, on which a wafer is placed;

a plurality of moving units configured to rotate the tables accordingly and move the tables in a predetermined direction in a horizontal plane;

a plurality of notch portion detecting units corresponding to the stage, the notch portion detecting units configured to detect circumferential positions of notch portions at edges of the wafer mounted on the stage, respectively; and

a controller configured to detect circumferential positions of the wafers via the notch portion detection unit, respectively, and to control positions of the stage in a horizontal plane via the moving unit to prevent interference between the wafers when the wafers mounted on the stage are rotated via the moving unit, respectively, so that the circumferential positions are aligned at positions in a predetermined circumferential direction, respectively, based on information on the circumferential positions,

wherein each of the plurality of tables includes a table body portion and a cushion member attached to an opening in the table body portion to hold a wafer,

wherein the cushion member further comprises:

a body portion attached to the opening, the body portion including a through-hole in a middle portion thereof;

a first annular portion on a front end side of the cushion member to abut against the wafer; and a first flange portion provided integrally with the first ring portion and the body portion, the first flange portion extending toward an outer side of the body portion.

According to this configuration, the spacer can be inserted into the opening (spacer attachment hole) in the table main body portion of the alignment apparatus while being deformed. Thus, the attachment of the gasket to the opening and the detachment thereof from the opening are easy.

In the aligning apparatus of the present invention, the cushion member may further include:

a second annular portion located on a rear end side of the cushion member, the second annular portion having the same shape as the first annular portion; and

a second flange portion provided integrally with the second annular portion and the body portion, the second flange portion being disposed in the body portion.

According to this configuration, the first annular portion and the second annular portion have a symmetrical structure. Thus, either of the first annular portion and the second annular portion may be the side in contact with the wafer. Further, erroneous mounting when the spacer is attached to the aligning device can be prevented, and attachment of the spacer is easy.

In the aligning apparatus of the present invention, the cushion member may further include:

a third flange portion provided integrally with the main body portion on a rear end portion side of the cushion member, the third flange portion extending toward an outer side of the main body portion.

According to this configuration, the packing can be easily attached to the opening of the table main body portion via the third flange portion.

In the alignment apparatus of the present invention, the stage main body portion may include a passage therein, one end portion of the passage being connected to the opening, and the other end portion of the passage being connected to the air intake and exhaust unit.

According to this configuration, when the cycle time is insufficient due to no adsorption, the wafer can be reliably held by providing separate intake and exhaust units and performing vacuum evacuation through the passage.

In the alignment device of the present invention, the main body portion may be a cylindrical member, and the first flange portion may include a tapered portion configured to be diametrically enlarged from the first annular portion side toward the main body portion side.

In the alignment device of the present invention, the second flange portion may include a tapered portion configured to be diametrically enlarged from the second annular portion side toward the main body portion side.

According to these configurations, the packing can be easily attached to the opening of the table main body portion.

In the alignment apparatus of the present invention, the cushion member may be attached to the table main body portion by clamping the table main body portion by the first flange portion and the second flange portion.

According to this configuration, the spacer can be prevented from falling off from the alignment device.

In the alignment apparatus of the present invention, the cushion member may be attached to the table main body portion by clamping the table main body portion by the first flange portion and the third flange portion.

According to this configuration, the spacer can be prevented from falling off from the alignment device.

In the alignment device of the present invention, the spacer member may be made of a conductive resin obtained by dispersing conductive particles in a resin composition.

According to this configuration, it is possible to prevent the wafer from being charged and accordingly to generate sparks, and to suppress the adhesion of particles to the wafer at the same time.

In the alignment device of the present invention, the outer diameter of the first annular portion may be smaller than the outer diameter of the body portion.

According to this configuration, the contact area between the wafer and the contact surface (first annular portion) of the pad can be reduced. Therefore, the adhesion of particles to the wafer caused by the contact between the wafer and the pad is suppressed.

The aligning apparatus of the present invention may further comprise an ID reading unit located at an intermediate position between the tables,

wherein the controller is configured to read the ID attached to the peripheral portion of the wafer via the ID reading unit while respectively detecting the circumferential position of the notch portion in the wafer via the notch portion detection unit by respectively rotating the wafer mounted on the stage via the moving unit, and simultaneously controlling the position of the stage in the horizontal plane via the moving unit to prevent interference between the wafers.

In the alignment apparatus of the present invention, the controller may include an interlock unit configured to control a position of the stage in a horizontal plane via the moving unit to prevent interference between the wafers loaded on the stage when the wafers are rotated by the moving unit.

In the alignment apparatus of the present invention, the controller may include an interlock unit configured to perform control to read an ID of one of the wafers, control a position of the stage in a horizontal plane via the moving unit, and perform control to read an ID of the other wafer so as to prevent interference between the wafers when the ID reading unit reads the IDs of the wafers mounted on the stage.

In the alignment apparatus of the present invention, the controller may include an interlock unit configured to control the position of the stage in the horizontal plane via the moving unit, and perform control to alternately read the IDs of the wafers with a time difference so as to prevent interference between the wafers when the ID reading unit reads the IDs of the wafers mounted on the stage.

In order to achieve the above object, the present invention provides a semiconductor wafer processing apparatus including the alignment apparatus having the above configuration, the semiconductor wafer processing apparatus further comprising:

a conveying device is arranged on the conveying device,

wherein the transfer device is configured to load and unload the wafer to and from each of a plurality of tables of the alignment device, the plurality of tables being arranged side by side in a horizontal plane.

In the semiconductor wafer processing apparatus of the present invention, the transfer device may be a double-arm robot.

In order to achieve the above object, the present invention provides an alignment method in which an alignment apparatus having the above configuration is used to align a wafer, the alignment method including:

loading the plurality of wafers into the plurality of tables arranged side by side in a horizontal plane, respectively;

holding a wafer via pad members respectively attached to the plurality of tables;

detecting a notch portion of a wafer on a stage while rotating the stage;

moving the position of the notch portion detected in the notch portion detection to a position in a predetermined circumferential direction by further rotating the stage;

performing a first control of a position of the stage to prevent interference between the wafers when the wafers are moved in the alignment operation, and

the wafers on the plurality of tables are unloaded from the plurality of alignment devices accordingly to be brought outside the alignment devices by an external unloading device.

In the alignment method of the present invention, (i) wafer loading, wafer unloading, or notch portion inspection in the area of one of the tables, and (ii) wafer loading, wafer unloading, or notch portion inspection in the area of the other of the tables may be performed continuously or partially overlapped.

In the alignment method of the present invention, when the notch portion detection determines that the positional displacement amount of the wafer with respect to the stage is out of the specified range, the wafer can be taken out from the alignment apparatus.

The alignment method of the present invention may further comprise: reading, by an ID reading unit at an intermediate position between the plurality of stages, IDs respectively attached to the plurality of wafers.

The alignment method of the present invention may further include a second control of the position of the stage to prevent interference between wafers in ID reading.

The alignment method of the present invention may further include a second control to restrict movement of the other of the wafers to the ID reading unit during reading of the ID of the one of the wafers, and to allow the other of the wafers to move to the ID reading unit after reading of the ID of the one of the wafers, so as to prevent interference between the wafers in the ID reading.

In the alignment method of the present invention, the stage in the horizontal plane may be moved to the take-out position to take out the wafer after reading the ID, thereby performing alignment.

Effects of the invention

According to the present invention, it is possible to provide an alignment apparatus capable of stably holding a wafer mounted on a stage of the alignment apparatus and facilitating replacement work such as attaching and detaching a cushion member.

According to the present invention, it is possible to provide an alignment apparatus which is compact and inexpensive with high throughput and capable of simultaneously aligning a plurality of wafers. It is also possible to prevent an unexpected situation in which expensive wafers are damaged due to collision with each other during an alignment operation or an ID reading operation.

Drawings

FIG. 1 is a perspective view of a gasket according to the present invention;

FIG. 2 is a front view of the pad;

FIG. 3 is a top view of the pad;

FIG. 4 is a sectional view taken along line IV-IV in FIG. 3;

FIG. 5 is a top view of a sorter having the alignment apparatus of the present invention mounted thereon;

FIG. 6 is a perspective view of the alignment device of the present invention;

FIG. 7 is an enlarged perspective view of the interior of the alignment device with the top, front and right side panels of the base box of the alignment device removed;

fig. 8 is a perspective view of a state where two wafers are mounted on the alignment device and one wafer is shown by a virtual line (two-dot chain line);

fig. 9 is a perspective view showing an example of a stage of the alignment apparatus;

fig. 10 is a view showing a stage on which a wafer is placed;

FIG. 11 is a sectional view taken along line XI-XI in FIG. 9;

FIG. 12A is a top view of the alignment fixture immediately after receiving two wafers;

FIG. 12B is a top view of the alignment fixture when the wafer is in the ID reading position;

FIG. 12C is a top view of the alignment fixture when the wafer is in the wafer removal position;

fig. 13 is a flowchart of an alignment operation and an ID reading operation in the alignment apparatus;

fig. 14 is a sectional view showing a modification of the gasket according to the present invention;

fig. 15 is a partially enlarged front view showing a deformation of the gasket according to the present invention;

fig. 16 is a partially enlarged front view showing a deformation of the gasket according to the present invention; and

fig. 17 is a partially enlarged front view showing a deformation of the gasket according to the present invention.

Detailed Description

Hereinafter, an alignment device and a cushion member according to an embodiment of the present invention are described with reference to the accompanying drawings.

First, a gasket 1 (an example of a gasket member) according to this embodiment is described with reference to fig. 1 to 4. For example, the spacer 1 is used as a member for holding a wafer (i.e., a material for manufacturing a semiconductor element). The spacer 1 is provided in an alignment device for aligning a notch portion at an edge of a wafer to a predetermined position in a circumferential direction. The pads 1 may be attached to a plurality of tables on which wafers are placed. Details of the alignment device are described below.

As shown in fig. 1 to 4, the cushion 1 includes, in the height direction (vertical direction in fig. 2), a main body portion 2 at a middle portion and holding portions 3 at both end portions of the main body portion 2. The holding portion 3 in the present embodiment includes a first holding portion 3A at one end portion (e.g., an upper end portion in fig. 2 and 4) of the main body portion 2 and a second holding portion 3B at an end portion (e.g., a lower end portion in fig. 2 and 4) opposite to the first holding portion 3A. The main body portion 2 and the holding portions 3A and 3B are integrally formed.

The body portion 2 is cylindrical in shape. The height of the main body 2 is set to be, for example, substantially the same as the thickness (vertical height in fig. 11) of the table main body portion 301 in the opening 302 (see fig. 11), which will be described below. The height of the body 2 is, for example, approximately 1mm to 2 mm. The outer diameter R1 of the main body 2 is the same as or slightly larger than the inner diameter of an opening 302 (see fig. 11) to be described below. Preferably, the outer diameter R1 of the body 2 is slightly larger than the inner diameter of the opening 302. This increases the degree of adhesion of the main body 2 to the opening 302 during attachment of the gasket 1 to be described below.

The intermediate portion of the body portion 2 and the intermediate portion of the holding portion 3(3A, 3B) are formed with through holes 5 to connect and pass through the body portion 2 and the holding portion 3(3A, 3B). The through-hole 5 in the present embodiment has a circular cross section and a uniform diameter in the height direction of the gasket 1.

The holding portion 3(3A, 3B) includes an annular portion 31(31A, 31B), and the annular portion 31(31A, 31B) abuts against the wafer or the like when the wafer or the like is held (placed) as a target member. The annular portion 31(31A, 31B) has an annular shape at an edge portion of the through-hole 5. The annular portion 31A and the annular portion 31B may have substantially the same shape. In the present embodiment, the annular portion 31A and the annular portion 31B each have a circular shape having the same diameter. The outer diameter R2 of the ring portion 31(31A, 31B) is smaller than the outer diameter R1 of the body portion 2. In other words, the outer diameter R2 of the annular portion 31(31A, 31B) is slightly larger (the value of the radial width W to be described below) than the diameter R4 (see fig. 4) of the through-hole 5. The annular portion 31(31A, 31B) is a substantially flat surface orthogonal to the height direction of the main body portion 2. The wafer is held in contact with either one of the annular portion 31A (an example of a first annular portion) of the first holding portion 3A or the annular portion 31B (an example of a second annular portion) of the second holding portion 3B.

The holding portion 3(3A, 3B) includes a flange portion 32(32A, 32B) provided integrally with the main body 2 and the annular portion 31(31A, 31B) and between the main body 2 and the annular portion 31(31A, 31B). The flange portion 32(32A, 32B) includes a tapered portion 33(33A, 33B) and a seating surface 34(34A, 34B). The tapered portion 33(33A, 33B) expands in diameter from the annular portion 31(31A, 31B) side toward the main body portion 2 side. The seating surface 34(34A, 34B) is a portion of the flange portion 32(32A, 32B) that contacts the main body 2, and is parallel to a surface orthogonal to the height direction of the main body 2. That is, the outer diameter R3 of the flange portion 32(32A, 32B) is larger than the outer diameter R1 of the main body 2. When cushion 1 is attached to tables 202a and 202B, seating surface 34(34A, 34B) abuts against a portion of tables 202a and 202B.

In this way, the holding portion 3(3A, 3B) has a truncated cone shape. The first holding portion 3A at the upper end portion of the body portion 2 has a diameter that decreases toward the annular portion 31A. The second holding portion 3B at the lower end portion of the body portion 2 has a diameter that decreases toward the annular portion 31B. The first holding portion 3A and the second holding portion 3B are symmetrical, with the main body portion 2 interposed between the first holding portion 3A and the second holding portion 3B. Although illustration is omitted, the bottom view of the pad 1 is the same as the top view shown in fig. 3. Further, the rear view and the left and right views of the cushion 1 are the same as the front view shown in fig. 2.

The area of the annular portion 31(31A, 31B) is, for example, 0.1 to 1 square millimeter (mm)²) Or smaller. When the area of the annular portion 31(31A, 31B) is less than 0.1mm²When contact with the wafer fails, a failure may occur. On the other hand, when the area of the annular portion 31(31A, 31B) is larger than 1mm²There may be particle adhesion problems to the wafer. For example, when the diameter R4 of the through-hole 5 is 4mm, and the radial width W of the annular portion 31(31A, 31B) is 0.01mm to 0.065 mm. Further, the area of the annular portion 31(31A, 31B) varies depending on the allowable total contact area S between all the pads 1 and the wafer (i.e., the number of pads 1). When the allowable total contact area S between all the pads 1 and the wafer is constant, the area of each annular portion 31(31A, 31B) is reduced to S, S/2, S/3. In other words, when the allowable total contact area S between all pads 1 and the wafer is determined and attached to the carrier of the alignment device 200When the number of pads 1 of tables 202a and 202B is determined, the area of the annular portion 31(31A, 31B) is uniquely determined.

Specifically, for example, when the total contact area S is 3mm²Or less, the number of the packing 1 is 3, the diameter R4 of the through-hole 5 is 4mm, and the outer diameter R2 of the ring portion 31(31A, 31B) is 4.13mm, and the radial width W of the ring portion 31(31A, 31B) is 0.065 mm. At this time, the area of the ring portion 31(31A, 31B) was 0.83mm²The total area of the annular portion 31 is 2.49mm²So as to satisfy the total contact area S (3 mm)²Or smaller). Further, for example, when the total contact area S is 0.5mm²Or less, the number of the packing 1 is 3, the diameter R4 of the through-hole 5 is 4mm, and the outer diameter R2 of the ring portion 31(31A, 31B) is 4.02mm, and the radial width W of the ring portion 31(31A, 31B) is 0.01 mm. At this time, the area of the ring portion 31(31A, 31B) was 0.13mm²The total area of the annular portion 31 is 0.39mm²So as to satisfy the total contact area S (0.5 mm)²Or smaller).

The main body portion 2 and the holding portions 3(3A, 3B) constituting the gasket 1 are made of a conductive resin obtained by dispersing conductive fine particles in a resin composition. For example, the main body portion 2 and the holding portion 3(3A, 3B) may be made of a fluororesin such as polytetrafluoroethylene, perfluoroalkoxyalkane, ethylene-tetrafluoroethylene copolymer, or the like. All resins generally used for the pad of a robot hand for processing semiconductor wafers can be used as the resin composition.

Next, an alignment apparatus 200 including tables 202a and 202b to which the pads 1 are attached is described with reference to fig. 5 to 13.

The alignment apparatus 200 according to the present embodiment is included in a semiconductor wafer processing apparatus. The alignment apparatus 200 aligns a wafer received from a transfer apparatus (robot) in a semiconductor wafer processing apparatus and simultaneously reads an ID attached to a peripheral portion of the wafer. The alignment of the wafer is performed by aligning the circumferential position of a notch portion (e.g., notch or orientation flat) at the edge of the wafer to a predetermined position in the circumferential direction.

(sorter)

In practice, such an alignment device 200 is used by being installed in a specific device called a sorter. A sorter is disposed at a position where the wafer is loaded into or unloaded from the semiconductor wafer processing apparatus. Fig. 5 is a top view showing the sorter 101.

As shown in fig. 5, the sorter 101 includes two load ports 105a and 105b attached to a front surface thereof, and one wafer transfer robot 103 and one alignment device 200 therein. The aligning device 200 is installed at an end portion (left end portion in fig. 5) in the inner space of the sorter 101. The robot 103 travels in the seating space of the alignment apparatus 200 to transfer the wafer 102. The robot 103 is a robot of a double-arm type (a double-arm robot), and includes a pair of arms 104.

The cover opening and closing mechanisms are interposed between the inside of the sorter 101 and the load port 105a, and between the inside of the sorter 101 and the load port 105b, respectively. When a container (e.g., FOUP) storing a plurality of wafers 102 is placed on the load ports, the lid opening and closing mechanism opens the lid of the container in a state where inflow of external air is blocked. Therefore, the internal space of the FOUP and the internal space of the sorter 101 are always maintained in a clean working environment.

Here, when a FOUP storing a plurality of wafers 102 having random orientations is loaded on one load port 105a, the lip of the FOUP is opened by the lid opening and closing mechanism. The robot 103 picks up two wafers 102 from the FOUP and transfers them to the alignment apparatus 200. The alignment apparatus 200 aligns the orientations of the two wafers 102 in a predetermined direction and simultaneously reads the ID embedded on the wafers 102.

Here, "orientation" of wafer 102 refers to its crystal orientation. In the present embodiment, the "orientation" of wafer 102 is synonymous with the "circumferential position" of the notched portion of wafer 102. The orientation of the wafer 102 "aligned in a predetermined direction" means that its "circumferential position" is "located at a predetermined position (reference position"), thereby completing the alignment of the wafer 102.

Next, the robot 103 takes out the two wafers 102 oriented in the predetermined direction from the alignment apparatus 200 and transfers the two wafers 102 to another FOUP at another load port 105 b.

The lid of the other FOUP is closed by the lid opening and closing mechanism when a predetermined number of wafers 102 oriented in a predetermined orientation are stored in the FOUP. The FOUP is then transferred by the external robot to the next processing step.

(alignment device)

Next, the structure of the alignment device 200 is described in detail with reference to fig. 6 to 8.

The alignment device 200 includes: two tables 202a and 202b on which the wafers 102a and 102b are placed (see fig. 8); two mobile units 204a and 204 b; two notch portion detection units 206a and 206 b; an ID reading unit 208; and a controller 210 (see fig. 7). The tables 202a and 202b are arranged side by side in a horizontal plane. The moving units 204a and 204b rotate the tables 202a and 202b, respectively, and move the tables 202a and 202b in a predetermined direction in a horizontal plane. Notch portion detection units 206a and 206b correspond to the tables 202a and 202b, and detect circumferential positions of the notch portions 112 at the edges of the wafers 102a and 102b respectively mounted on the tables 202a and 202b (see fig. 8 and 9). The ID reading unit 208 reads the IDs of the wafers 102a and 102 b.

In fig. 8, the outline of only the wafer 102a placed on the stage 202a is indicated by a two-dot chain line. This is for easy understanding of the positional relationship between the wafer 102a and the stage 202 a. Reference numeral 215 in fig. 7 denotes wiring from the controller 210 to various devices.

Tables 202a and 202b protrude from openings 230a and 230b in top plate 211a of box-shaped base 211 of alignment apparatus 200. Tables 202a and 202b include pads 1 (not shown in fig. 6) that attract and hold wafers 102a and 102b mounted thereon.

The notch portion detection units 206a and 206b are located at the right and left end portions of the alignment apparatus 200. Similar to the tables 202a and 202b, upper halves of C-shaped notch portions (described below) of the notch portion detection units 206a and 206b protrude from openings 232a and 232b in the top plate 211a of the box-shaped base 211 of the alignment apparatus 200.

The ID reading unit 208 is located at an intermediate position between the two mobile units 204a and 204 b. More specifically, the ID reading unit 208 is located at an intermediate position between the two moving units 204a and 204b, and is located directly below a square hole in the top plate 211a of the box-shaped base 211. The ID reading unit 208 can read the ID attached to the peripheral portion of the wafer 102 through the hole. Here, the peripheral portion of wafer 102 refers to an outer peripheral portion of wafer 102 that includes an edge of wafer 102.

(detailed construction of Mobile Unit)

Next, the structure of the mobile units 204a and 204b is described in detail with reference to fig. 7. The mobile unit 204a and the mobile unit 204b have the same structure and are symmetrical. Therefore, in the following description, only the mobile unit 204a is described in detail, and the description of the mobile unit 204b is omitted.

In fig. 7, arrows X and Y indicate horizontal directions orthogonal to each other. The arrow X indicates a width direction as a first horizontal direction, and the arrow Y indicates a depth direction as a second horizontal direction.

The moving unit 204a is a table driving mechanism, and the moving unit 204a rotates the table 202a and simultaneously moves the table 202a in a predetermined direction in a horizontal plane in a state where the wafer 102a is placed on the table 202 a. The moving unit 204a includes a stage driving motor 224a, an X-axis slider 216a, and a Y-axis slider 220 a.

The stage driving motor 224a is located on the lower surface of the Y-axis slider 220a, and the output shaft 241 of the stage driving motor 224a protrudes from an opening (not shown) in the Y-axis slider 220 a. The tip of the output shaft 241 is coupled to the table 202a such that the table 202a is rotated by the rotation of the table driving motor 224 a. The stage driving motor 224a is inserted into an opening OP1 in the center of the X-axis slider 216 a. Thus, when the Y-axis slider 220a moves, the stage driving motor 224a does not interfere with the X-axis slider 216 a.

The Y-axis slider 220a is driven in the Y-axis direction by a Y-axis driving ball screw unit 223a, and slides over a pair of left and right Y-axis linear guides 221a and 221a on the X-axis slider 216 a.

The Y-axis drive ball screw unit 223a is fixed to the X-axis slider 216a via a bracket. The ball screw of the Y-axis driving ball screw unit 223a is screwed by rotation of the Y-axis driving motor 222 a. As described above, the Y-axis slider 220a slides over the pair of left and right Y-axis linear guides 221a and 221a, and moves in the Y-axis direction.

The X-axis slider 216a is driven in the X-axis direction by an X-axis driving ball screw unit 219a, and slides over a pair of upper and lower X-axis linear guides 217a and 217a on the rear wall of the box-shaped base 216 a.

The X-axis driving ball screw unit 219a is fixed to the left wall of the box-shaped base 211. The ball screw of the X-axis driving ball screw unit 219a is screwed by rotation of the X-axis driving motor 218 a. As described above, the X-axis slider 216a slides over the pair of upper and lower X-axis linear guides 217a and 217a, and moves in the X-axis direction.

(operation of Mobile Unit)

The moving unit 204a controls the stage driving motor 224a via the controller 210 to rotate the stage 202a on which the wafer 102a is mounted, and simultaneously controls the X-axis driving motor 218a and the Y-axis driving motor 222a via the controller 210 to move the X-axis slide 216a and the Y-axis slide 220a in a predetermined direction on a horizontal plane. As a result, the stage 202a on which the wafer 102a is placed moves in a predetermined direction in the horizontal plane.

(detailed construction of notch portion detecting Unit)

As shown in fig. 7, each of the notch portion detection units 206a, 206b includes a notch 291 at an intermediate portion in a length direction of a rectangular member elongated in the vertical direction. The entire recess 291 has a C-shaped profile. The notch portion detecting units 206a and 206b are arranged such that the notches 291 face each other. The edges of the wafers 102a and 102b mounted on the stages 202a and 202b pass through the notches 291 (see fig. 8). A laser projection unit facing the notch portion 291 is located on one of the upper portion or the lower portion of each of the notch portion detection units 206a and 206b, and a laser reception unit is located on the other portion.

(operation of notch portion detecting unit)

The notch portion detection units 206a and 206b irradiate the laser light projected from the laser projection unit to the edges of the rotating wafers 102a and 102b, respectively, passing through the notch 291. Thus, the change in the contour shape of the edge of the wafer 102 is continuously detected. The notch portion (notch, orientation flat, etc.) at the edge is detected by a change in the amount of laser light received by the light receiving unit through the edge, thereby detecting the circumferential position thereof. Meanwhile, the center positions of the wafers 102a and 102b are detected by the previously known diameters of the wafers 102a and 102b and the incident angles and incident depths of the laser light to the wafers 102a and 102b passing through the notch 291, respectively.

(detailed Structure of cushion attached to Table)

Next, the tables 202a and 202b are described with reference to fig. 9 to 11, and the cushion 1 is attached to the tables 202a and 202 b.

Fig. 9 is a perspective view showing the table 202a to which the cushion 1 is attached. Fig. 10 is a view showing the stage 202a when a wafer is placed thereon. Fig. 11 is a cross-sectional view XI-XI of the table 202a with the pad 1 attached. As described above, since the tables 202a and 202b have substantially the same structure, the table 202a is representatively described below.

As shown in fig. 9 and 10, a plurality of (three in the present embodiment) pads 1 for holding the wafer 102a are attached to the stage 202 a. The table 202a includes an air intake and exhaust unit (not shown), and each of the pads 1 is connected to the air intake and exhaust unit. The pad 1 attached to the stage 202a holds the wafer 102a by vacuum-sucking the wafer 102a so that the wafer 102a does not shift with respect to the stage 202a or fall off the stage 202 a. The stage 202a is made of a ceramic material such as alumina.

As shown in fig. 11, the stage 202a includes a stage main body portion 301, an opening 302 for attaching the cushion 1, a passage 303 (a part of the air intake and exhaust unit) connected to the opening 302, and a loading surface 304 (i.e., a surface on which the wafer 102a is loaded).

The opening 302 is a hole in a mounting surface 304 (upper surface in fig. 11), i.e., a surface on which the wafer 102a is held on the stage main body portion 301. The opening 302 is connected to a channel 303. The opening 302 in the present embodiment has a circular cross section and a uniform diameter in the thickness direction of the table main body portion 301 in the opening 302. The diameter of the opening 302 is substantially the same as the outer diameter R1 of the body 2 of the gasket 1.

In the passage 303, a groove is present in a surface (inner surface) 305 opposed to the mounting surface 304 of the stage main body portion 301, and the groove is sealed by a cover member (sealing member) 306. The surface of the cover member (sealing member) 306 opposite to the channel 303 is supported by the base 307. An end portion (left end portion in fig. 11) of the passage 303 is connected to an intake and exhaust unit (not shown).

The holding portion 3(3A or 3B) on either side of the packing 1 is inserted into the opening 302 from the loading surface 304 side of the table main body portion 301 while being elastically deformed. At this time, since the flange portion 32(32A, 32B) includes the tapered portion 33(33A, 33B), the holding portion 3(3A or 3B) is guided into the opening 302 while being automatically adjusted. Then, the maximum diameter portion 321 (see fig. 11) of the flange portion 32(32A, 32B) is folded back and elastically deformed toward the main body portion 2, and is elastically deformed into its original shape after passing completely through the opening 302, so that the holding portion 3(3A or 3B) is brought into close contact with the lower edge of the opening 302. For example, when the second holding portion 3B is inserted into the opening 302, the flange portion 32B (tapered portion 33B) of the second holding portion 3B enters the opening 302, so that the second holding portion 3B (annular portion 31B and flange portion 32B) is located in the passage 303. Accordingly, the seating surface 34B of the second holding portion 3B arranged in the passage 303 abuts (seats) against the inner wall surface of the passage 303 (the upper surface of the passage 303 in fig. 11).

At this time, the main body portion 2 of the packing 1 abuts against the inner peripheral surface of the opening 302 so that the two are in close contact with each other. Further, the first holding portion 3A, which is not inserted into the opening 302, is located outside the opening 302 (above the placement surface 304 in fig. 11) such that the seating surface 34A of the first holding portion 3A is attached in contact with the placement surface 304. That is, by sandwiching the table main body portion 301 by the flange portion 32A of the first holding portion 3A and the flange portion 32B of the second holding portion 3B, the packing 1 is attached in firm close contact with the table main body portion 301. In this way, the attachment position of the cushion 1 to the table 202A is defined to an appropriate position by the flange portion 32A of the first holding portion 3A and the flange portion 32B of the second holding portion 3B.

When the cushion 1 is attached to the table 202a via the opening 302, the through hole 5 of the cushion 1 is connected to the passage 303 of the table 202 a. In this state, the air in the through-hole 5 and the passage 303 is vacuum-evacuated by the operation of the air intake and exhaust unit, and thus the wafer 102a is vacuum-sucked onto the ring-shaped portion 31A of the cushion 1 attached to the stage 202 a.

In the present embodiment, three pads 1 are attached to one table 202 a. Therefore, the contact area between the pad 1 (the ring portion 31A) and the wafer 102a on the stage 202a is 3mm²Or smaller.

(alignment method)

Next, an alignment method of the wafers 102A and 102b after the operation of the alignment apparatus 200 is described in detail with reference to fig. 12A to 12C and in the order of steps in the flowchart in fig. 13. The alignment method comprises the following steps: transferring wafers 102a and 102b to alignment apparatus 200; detecting notch portions 112 in wafers 102a and 102b in alignment apparatus 200; reading the ID of wafers 102a and 102 b; aligning the wafers 102a, 102 b; wafers 102a and 102b are removed from alignment apparatus 200. In fig. 13, wafer 102a is referred to as a "first wafer", wafer 102b is referred to as a "second wafer", and stage 202a is referred to as a "first stage".

(wafer Transmit-receive wafer)

First, the wafers 102a and 102b are transferred (loaded) to the tables 202a and 202b, respectively, by the robot 103 (see fig. 5) (step S1).

Fig. 12A shows a state of the alignment apparatus 200 immediately after the wafers 102A and 102b are transferred to the alignment apparatus 200. The wafers 102a and 102b received on the tables 202a and 202b are vacuum-sucked on pads 1 (see fig. 9) attached to the tables 202a and 202b, respectively.

In fig. 12A, in order to facilitate understanding of the positional relationship between the wafer 102A and the stage 202A, only the outline of the wafer 102A mounted on the stage 202A is shown by a two-dot chain line. Table 202b is not shown. The same description and illustration omission also apply to fig. 12B and 12C.

Thus, when the wafers 102A and 102b are placed on the alignment apparatus 200, the stage 202A receiving the wafer 102A is in the initial position (starting point: center of the opening 230 a) as shown in FIG. 12A. In contrast, the center position 102ac of the wafer 102a on the stage 202a is generally offset from the center position 202ac of the stage 202 a.

Thus, the state of the two offset center positions 102ac and 202ac also applies to the wafer 102b and the stage 202 b.

(notch part inspection-inspecting notch part and center position of wafer)

Next, the alignment apparatus 200 detects the notch portions 112 and the center positions 102ac and 102bc of the wafers 102a and 102b (step S2).

The detection is performed as follows. That is, the controller 210 rotates the tables 202a and 202b via the moving units 204a and 204b, so that the wafers 102a and 102b mounted on the tables 202a and 202b are rotated. Meanwhile, via the notch portion detecting units 206a and 206b, the controller 210 detects circumferential positions of the notch portions 112 of the wafers 102a and 102b at the edges of the notches 291 of the notch portion detecting units 206a and 206b while the wafers 102a and 102b are rotated, and detects center positions 102ac and 102bc of the wafers 102a and 102 b. The inspection is performed on both wafers 102a and 102b simultaneously in the same order.

Here, the circumferential position of the notch portion 112 in the wafers 102a and 102b refers to a relative position of the notch portion 112 with respect to the starting point of the rotation angle of the tables 202a and 202 b. The center positions 102ac and 102bc of the wafers 102a and 102b refer to the positions of the wafers 102a and 102b with respect to the center positions 202ac and 202bc of the tables 202a and 202 b.

Next, the controller 210 determines whether the detected center positions 102ac and 102bc of the wafers 102a and 102b are within a predetermined range of a specified value (step S3).

When determining that the center positions 102ac and 102bc of the wafers 102a and 102b are out of the specified value range (no in step S3), the controller 210 determines that the positional shift amount of the center position of the corresponding wafer is out of the specified range, so that the wafer is regarded as abnormal. The controller 210 then stops operation of the alignment device 200 and issues an alarm. At this time, the wafer regarded as abnormal is removed from the alignment apparatus 200, and the wafer transfer process is performed again.

Such determination and device operation based on the determination may also be performed in step S2.

(ID read-read wafer ID)

On the other hand, if it is determined in step S3 that the center positions 102ac and 102bc of the wafers 102a and 102b are within the predetermined range of the specified values (yes in step S3), the alignment apparatus 200 reads the IDs of the wafers 102a and 102b (steps S4 to S6).

Fig. 12B shows a state where the wafer 102a is moved to the ID reading position. Hereinafter, an operation of the alignment apparatus 200 to read the ID of the wafer 102a is described with reference to fig. 12B.

(ID read preparation)

First, the alignment apparatus 200 reads the ID of the wafer 102 a. At this time, the controller 210 determines whether the wafer 102b is out of the ID reading position before the wafer 102a is moved to the ID reading position (step S4).

When it is determined that the wafer 102b is not outside the ID reading position (at the ID reading position) (no in step S4), the controller 210 moves the wafer 102b while waiting for the wafer 102a to be moved to the ID reading position to prevent interference between the wafers 102a and 102 b. Specifically, the controller 210 controls the position of the stage 202b in the horizontal plane via the moving unit 204b, and moves the wafer 102b mounted on the stage 202b out of the ID reading position.

When it is determined that the wafer 102b is in the ID reading position even after the wafer 102a is held waiting for a predetermined time, the controller 210 stops the operation of the alignment apparatus 200 and issues an alarm.

(ID reading)

When it is determined that the wafer 102b is outside the ID reading position (not at the ID reading position) after such ID reading preparation (yes in step S4), the controller 210 moves the wafer 102a to the ID reading position (step S5).

The movement is performed as follows. That is, the controller 210 controls the X-axis drive motor 218a, the Y-axis drive motor 222a, and the stage drive motor 224a via the moving unit 204a based on data relating to the circumferential position of the notch portion 112 of the wafer 102a and the center position 102ac of the wafer 102a obtained in the previous notch portion detection. Then, the controller 210 horizontally and rotationally moves the stage 202a so that the portion where the ID is embedded on the peripheral portion of the wafer 102a comes directly above the ID reading unit 208. Accordingly, the wafer 102a moves to the ID reading position. According to the standard, the ID of the wafer is embedded at a position spaced apart from the notch portion in the wafer by a predetermined angle, so that such control can be performed.

In this way, when the wafer 102a reaches the ID reading position, the controller 210 reads the ID of the wafer 102a via the ID reading unit 208 (step S6).

Next, the controller 210 determines whether the ID reading unit 208 reads the ID of the wafer 102a (step S7). When the ID of the wafer 102a is not correctly read (no in step S7), the controller 210 instructs to retry reading the ID. This ensures reading of the ID.

On the other hand, when the ID of the wafer 102a is correctly read (yes in step S7), the controller 210 controls the position of the stage 202a in the horizontal plane via the moving unit 204a so that the wafer 102a is moved to the next position for taking out the wafer. At the same time, the controller 210 controls the position of the stage 202b in the horizontal plane via the moving unit 204b so that the wafer 102b is moved to the ID reading position.

(interlock for preventing interference between wafers-second position control)

Next, a method for preventing interference between the wafers 102a and 102b when the wafer 102a is in the ID reading state is described.

As described above, in the ID reading preparation (step S4), while waiting for the wafer 102a to move to the ID reading position, the controller 210 controls the position of the stage 202b in the horizontal plane via the moving unit 204b to prevent interference between the wafers 102a and 102 b. Accordingly, the controller 210 moves the wafer 102b mounted on the stage 202b out of the ID reading position. Here, the controller 210 has an interlock function of controlling the positions of the tables 202a and 202b in the horizontal plane via the moving units 204a and 204b to prevent interference between the wafers 102a and 102 b.

The alignment method of the present embodiment includes interlocking based on this function. The evacuation movement of the wafer 102b from the ID reading position in the ID reading preparation (step S4) is an example of utilizing this function. In the ID reading, a step specifically prepared for utilizing this function is referred to as "second position control" in this specification.

The interlock function not only prevents interference between the wafers, but also helps prevent the IDs of two wafers from being read at the same time because one wafer always reaches the position of the ID reading unit 208 through the above-described sequence.

In the aligning apparatus 200 of the present embodiment, an interlock unit based on an interlock function is also mounted to the controller 210.

Here, an example of the interlock method employed in the "second position control" is described. Examples of the interlocking method include the following methods (1) to (3).

(1) The controller 210 controls the positions of the stages 202a and 202b in the horizontal plane via the moving units 204a and 204b to prevent interference between the two wafers 102a and 102 b.

The controller 210 controls the position of the tables 202a and 202b because the controller 210 stores a history of the center positions 202ac and 202bc of the tables 202a and 202 b.

(2) This method is employed in the present embodiment described above, and is a specific example of the method (1). For example, in order to prevent interference between the two wafers 102a and 102b, the controller 210 performs control to read the ID of one wafer 102a, control the positions of the stages 202a and 202b in the horizontal plane via the moving units 204a and 204b, and perform control to read the ID of the other wafer 102 b. Accordingly, the controller 210 restricts the movement of one wafer 102a to the ID reading unit 208 while the ID of the other wafer 102b is read, and moves the other wafer 102b to the ID reading unit 208 after the ID of the one wafer 102a is read.

(3) In order to prevent interference between the two wafers 102a and 102b, the controller 210 may control the positions of the stages 202a and 202b in the horizontal plane via the moving units 204a and 204b, and perform control so as to alternately read the IDs of the wafers 102a and 102b with a time difference.

(alignment and wafer unload-alignment and removal of wafer 102)

When the ID of the wafer 102a is read in steps S6 and S7, the controller 210 moves the wafer 102a to the wafer take-out position and aligns the notch portion 112 in the wafer 102a (step S8).

Fig. 12C shows a state immediately after the wafer 102a is moved to the wafer take-out position to align the notch portion 112 of the wafer 102 a.

The movement of the wafer 102a to the wafer take-out position and the alignment of the notch portion 112 of the wafer 102a are performed as follows. The controller 210 controls the X-axis drive motor 218a, the Y-axis drive motor 222a, and the stage drive motor 224a via the moving unit 204a based on the data on the circumferential position of the notch portion 112 of the wafer 102a and the center position 102ac of the wafer 102a obtained in the aforementioned notch portion detection. Accordingly, the wafer 102a is moved to the position for the arm 104 of the robot 103 to take out the wafer 102a, and simultaneously rotated so that the notch portion 112 reaches a predetermined position in the circumferential direction.

Accordingly, the alignment of the wafer 102a is completed, the wafer 102a is taken out by the robot 103, and a new wafer is placed on the stage 202a of the alignment apparatus 200.

(relationship between positions)

Next, the relationship between the taking-out position and the alignment position of the wafer 102a, the initial position of the stage 202a, and the "predetermined position in the circumferential direction" is described in detail.

As described above, notch portion 112 in wafer 102a is aligned with the removal position of wafer 102 a. In other words, the notch portion 112 of the wafer 102a in the take-out position is located on the side of the robot 103 in fig. 5 (the right side in fig. 5), and the direction thereof is aligned in the predetermined direction (the Y direction in fig. 12C). In addition, as shown in fig. 12C, the position of the notch portion 112 in the X direction is set at the same position as the center of the opening 230a (initial position of the table 202A in fig. 12A). At this time, when the wafer 102a is transferred to the stage 202a, the center position 202ac of the stage 202a and the center position 102ac of the wafer 102a may not coincide with each other depending on the relative position therebetween, as shown in fig. 12C.

The taking-out position of the wafer 102a refers to a "predetermined position in the circumferential direction" when the wafer 102a is aligned.

In this state (state where the position and orientation are aligned), the wafer 102a waits for the robot 103 to correctly take out the wafer 102 a. Therefore, when the wafer 102a is taken out by the robot 103, the center position 102ac of the wafer 102a coincides with the center position of the wafer placement portion of the arm 104 of the robot 103. Therefore, the robot 103 does not have to finely adjust the wafer receiving position to align the two center positions, eliminating the loss of wafer transfer time and improving the throughput of the apparatus.

(interlock for preventing interference between wafers-first position control)

Next, a method for preventing interference between the wafers 102a and 102b when the wafer 102a is in alignment is described.

When wafer 102a is moved to the wafer removal position, notch portions 112 in wafer 102a are aligned. At this time, as described above, the center position 202ac of the stage 202 may not coincide with the center position 102ac of the wafer 102 a. In this case, the center position 202ac of the stage 202a is offset from the center position 102ac of the wafer 102a, as shown in fig. 12C. Thus, when wafer 102a is rotated to align notched portions 112, wafer 102a is rotated in an offset state.

On the other hand, the wafer 102b is positioned on the stage 202b and is in wafer transfer, ID read preparation, ID read, alignment, or wafer retrieval. Depending on the situation, the operation of the wafer 102b is out of order and may also be in notch portion inspection. Even in any step, the wafer 102b and the stage 202b may be in a deviated state, as in the case of the wafer 102a and the stage 202a (see fig. 9A to 9C).

Therefore, it is necessary to provide a method for preventing either or both of wafer 102a and wafer 102b from interfering with each other when either wafer 102a or wafer 102b is rotated for either of the processing steps.

In the wafer alignment according to the alignment method of the present embodiment, the "interlock function" of the controller 210 described above is used as such a method. In this specification, the specific preparation step is referred to as "first position control".

Here, the interlock method employed in the "first position control" is the same as the interlock method (1) employed in the "second position control", and the controller 210 controls the positions of the tables 202a and 202b in the horizontal plane via the moving units 204a and 204b to prevent interference between the two wafers 102a and 102 b.

(execution mode in alignment method)

Next, various combination patterns of steps in the alignment method of the present embodiment are described.

In the alignment apparatus 200, two tables 202a and 202b arranged side by side in a horizontal plane may be independently controlled by the controller 210. Therefore, in the alignment method according to the present embodiment, steps other than ID reading can be independently performed with respect to the wafers 102a and 102b mounted on the stage. Further, in the alignment method according to the present embodiment, it may be necessary to independently perform each step based on the history of the aforementioned steps performed on the wafers 102a and 102 b.

In the alignment method according to the present embodiment, the step of transferring the wafer 102a, taking out the wafer 102a, or inspecting the notch portion of the wafer 102a in the area of the stage 202a, and the step of transferring the wafer 102b, taking out the wafer 102b, or inspecting the notch portion of the wafer 102b in the area of the stage 202b may be performed continuously or partially overlapping. When these steps are performed in a combined manner, there may be various modes of operation combinations of the apparatuses (robot and notch portion detecting unit) that perform these steps.

Hereinafter, typical examples of such modes are enumerated and described.

In addition, mode (3) to be described below is an example in which three tables 202a, 202b, and 202c are provided as a modification of the present embodiment.

In mode (1), the transfer operation of the wafer 102a or the take-out operation of the wafer 102a in the area of the stage 202a and the detection operation of the notch portion 112 in the mounted wafer 102b mounted in the area of the stage 202b are continuously or partially performed overlapping.

In mode (2), the inspection operation of the notch 112 in the wafer 102a mounted in the area of the stage 202a and the inspection operation of the notch portion 112 in the wafer 102b mounted in the area of the stage 202b are continuously or partially overlapped.

In mode (3), the transfer operation of the wafer 102a in the area of the stage 202a, the take-out operation of the wafer 102b in the area of the stage 202b, and the detection operation of the notch portion 112 in the wafer 102c mounted in the area of the stage 202c are continuously or partially overlapped.

As described above, the aligning apparatus 200 according to the present embodiment includes: tables 202a and 202b arranged side by side in a horizontal plane, the wafers 102a and 102b being placed on the tables 202a and 202 b; moving units 204a and 204b that rotationally move the tables 202a and 202b, respectively; two notch portion detection units 206a and 206b that detect circumferential positions of the notch portions 112 at edges of the wafers 102a and 102b mounted on the stages 202a and 202b, respectively; and a controller 210 that controls the positions of the tables 202a and 202b in the horizontal plane via the moving units 204a and 204b to prevent interference between the wafers 102a and 102b when the circumferential positions of the notch sections 112 of the wafers 102a and 102b are aligned in predetermined positions. Each of tables 202a and 202b includes a table body portion 301 and at least one pad 1 attached to an opening 302 in table body portion 301 to hold wafers 102a and 102 b. The gasket 1 includes: a body portion 2 attached to the opening 302 and having a through-hole 5 in a central portion thereof; an annular portion 31 located at an end portion of the pad 1 to abut against the wafers 102a and 102 b; and a flange portion 32 provided integrally with the ring portion 31 and the body portion 2 and extending toward the outside of the body portion 2. The outer diameter R2 of the ring portion 31 is smaller than the outer diameter R1 of the body portion 2. According to this configuration, the contact area between the wafers 102a and 102b and the annular portion 31A of the gasket 1 is reduced. Therefore, the adhesion of particles to the wafers 102a and 102b caused by the contact between the wafers 102a and 102b and the pad 1 is suppressed. According to this configuration, the pad 1 is attached to the alignment device 200 only by deforming the pad 1 to press the pad 1 and inserting the pad 1 into the opening 302 of the table main body portion 301 serving as a pad loading hole. For this reason, no special tool or member is required in attaching the gasket 1 to the opening 302 and detaching the gasket 1 from the opening 302. Therefore, the attaching and detaching work is easy, and the component cost associated with the attaching and detaching is zero. Further, since the pad 1 is made of a resin composition containing conductive fine particles, by bringing the pad 1 into contact with the wafer, the static electricity charged on the wafer is grounded. As a result, no spark is generated between the pad 1 and the wafer. Therefore, the wafer is not damaged and the yield thereof is improved.

In the aligning apparatus 200 of the present embodiment, the annular portion 31 includes an annular portion 31A (an example of a first annular portion) on the front end side of the packing 1 and an annular portion 31B (an example of a second annular portion) having the same shape as the annular portion 31A on the rear end side of the packing 1. The flange portion 32 includes a flange portion 32A (an example of a first flange portion) provided integrally with the ring portion 31A and the main body portion 2, and a flange portion 32B (an example of a second flange portion) provided integrally with the ring portion 31B and the main body portion 2. In this way, since the ring portion 31A and the ring portion 31B have a symmetrical structure, any one of the ring portion 31A and the ring portion 31B may be a side that contacts the wafer. Further, since the flange portion 32A and the flange portion 32B have a symmetrical structure, erroneous mounting when the gasket 1 is attached to the alignment device 200 is prevented, and attachment of the gasket 1 is easy.

In the alignment apparatus 200 of the present embodiment, the stage main body portion 301 includes a passage 303 therein. One end portion of the passage 303 is connected to the opening 302, and the other end portion thereof is connected to the intake and exhaust unit. Therefore, when the cycle time without adsorption and wafer transfer is insufficient, or when the adsorption force is insufficient, the wafers 102a and 102b can be transferred in a state of being reliably held by the additional intake and exhaust units separately provided and performing vacuum evacuation through the passage 303.

In the alignment apparatus 200 of the present embodiment, when the packing 1 is attached to the table main body portion 301, the table main body portion 301 is clamped by the flange portions 32A and 32B, so that the packing 1 is held in firm close contact with the table main body portion 301. This prevents the spacer 1 from falling off the aligning apparatus 200.

According to the aligning apparatus 200 of the present embodiment, when the packing 1 is worn by use, only the packing 1 can be removed and replaced without replacing the aligning apparatus 200 itself. During replacement, the gasket 1 can be manually and easily detached and attached without special tools, members, etc. Furthermore, the pad 1 does not need to be distinguished from the front and back during the first attachment, and the opposite back side (one side in the channel 303) thereof is reused once the pad 1 is detached after the first attachment to use the front side thereof. Therefore, the time required for the replacement work is greatly reduced, and the component cost is not required for the replacement. Further, one pad 1 may be used twice.

According to the gasket 1 of the present embodiment, when the gasket 1 is attached to the aligning apparatus 200, since the attachment of a sealing member such as a vacuum adsorption gasket disclosed in JP-B-4720790 is not required, the replacement work of the gasket 1 is easier.

Due to the configuration and operation of the alignment device 200 of the present embodiment as described above, the following effects can be obtained.

(1) In the alignment apparatus 200 of the present embodiment, a plurality of wafers 102a and 102b can be aligned simultaneously. The alignment apparatus has a compact size, low cost, and high throughput while including the ID reading unit 208.

(2) The alignment apparatus 200 of the present embodiment can prevent an unexpected situation in which the expensive wafers 102a and 102b are damaged due to collision with each other during the alignment operation (the detection operation of the circumferential position of the notch portion 112 in the wafers 102a and 102b and the alignment operation) and the ID reading operation. Further, the alignment apparatus 200 of the present embodiment can prevent the IDs of the wafers 102a and 102b mounted on the stages 202a and 202b from being read at the same time, and prevent the process histories of the wafers 102a and 102b from being mixed up.

Due to the above-described configuration and operation of the semiconductor wafer processing apparatus (including the sorter 101) of the present embodiment, the following effects can be obtained.

The semiconductor wafer processing apparatus of the present embodiment further includes a robot 103 in addition to the alignment apparatus 200. The robot 103 may load (transfer) the wafers 102a and 102b to a plurality of tables 202a and 202b, respectively, arranged side by side in the horizontal plane of the alignment apparatus 200, and take out the wafers 102a and 102b from the tables 202a and 202 b. Thus, the processing speed of alignment and delivery of the wafers 102a and 102b is increased, and the throughput of the semiconductor wafer processing apparatus can be improved. Further, by using the robot 103 of the double arm type, when transferring wafers between the robot 103 and the alignment apparatus 200, two wafers 102a and 102b can be taken out and transferred at a time, so that the throughput of the semiconductor wafer processing apparatus can be further improved.

Since the alignment method of the present embodiment is configured as described above, the following effects can be obtained.

(1) According to the alignment method of the present embodiment, since the plurality of wafers 102a and 102b can be aligned at the same time and include ID reading, the semiconductor wafer processing apparatus has a compact size, low cost, and high throughput.

(2) According to the alignment method of the present embodiment, an unexpected situation in which the expensive wafers 102a and 102b are damaged due to collision with each other during the alignment operation (positioning operation) and the ID reading operation can be prevented. Further, according to the alignment method of the present embodiment, the IDs of the wafers 102a and 102b mounted on the stages 202a and 202b can be prevented from being read at the same time, and the process histories of the wafers 102a and 102b can be prevented from being mixed up.

(3) According to the alignment method of the present embodiment, the plurality of tables 202a and 202b may perform the steps independently of the steps of the other tables 202b and 202a, except for the ID reading. Therefore, the degree of freedom in transferring the wafer to the alignment apparatus 200 and taking the wafer out of the alignment apparatus 200 can be increased, and the throughput of the apparatus can be further improved.

(4) According to the alignment method of the present embodiment, even when the wafers 102a and 102b are in an abnormal position due to some failure in wafer transfer, an unexpected situation such as damage due to collision between the wafers 102a and 102b can be prevented in the later step.

(5) According to the alignment method of the present embodiment, the center positions 102ac and 102bc of the wafers 102a and 102b and the center position of the wafer loading portion (hand) of the arm of the robot 103 are aligned. Therefore, the robot 103 does not have to finely adjust the wafer receiving position, the loss of wafer transfer time between the alignment apparatus 200 and the robot 103 is eliminated, and the throughput of the apparatus can be further improved.

(variants of the embodiments)

In the above-described embodiment, the holding portion 3 including the ring portion 31 and the flange portion 32 is located at both end portions of the body portion 2, but the present invention is not limited thereto. The holding portion 3 may be provided on at least one end portion of the body portion 2. For example, as in the packing 1A shown in fig. 14, a holding portion having a shape different from that of the holding portion 3 of the above embodiment may be provided at an end portion (lower end portion in fig. 14) of the main body portion 2 inserted into the table main body portion 301. Specifically, in the packing 1A, the holding portion 3BA inserted into the stage main body portion 301 includes a flange portion 32BA (an example of a third flange portion) extending toward the outside of the main body portion 2. The flange portion 32BA includes: a surface 35BA at the edge of the through-hole 5, which is parallel to a surface orthogonal to the height direction of the body 2; a surface 33BA perpendicular to the outer end portion of the main body portion 2 from the surface 35 BA; and a surface (seating surface) 34BA at a portion of the flange portion 32BA contacting the main body portion 2, which is parallel to a surface orthogonal to the height direction of the main body portion 2. With this configuration, by sandwiching the table main body portion 301 with the flange portions 32A and 32BA on both ends of the main body portion 2, the packing 1A can also be attached to the alignment device 200 to be firmly brought into close contact with the alignment device 200. Therefore, the spacer 1A can be prevented from falling off from the aligning apparatus 200.

In the above-described embodiment, the main body portion 2 has a cylindrical shape, but the present invention is not limited thereto. The body 2 is appropriately selected according to the shape of the opening 302, and may be a prismatic shape such as a quadrangular prism or a polygonal column.

In the above-described embodiment, the holding portion 3(3A, 3B) has a truncated cone shape, but the present invention is not limited thereto. The holding portion 3 is also appropriately selected in accordance with the shape of the opening 302, and may be, for example, a truncated pyramid shape.

In the above-described embodiment, the annular portion 31(31A, 31B) has a substantially flat shape orthogonal to the axial direction of the main body portion 2, but the present invention is not limited thereto. For example, the ring portion 31(31A, 31B) may be an inclined surface gradually inclined to the flange portion 32(32A, 32B) toward the inside thereof (toward the through hole 5), or an inclined surface gradually inclined to the flange portion 32(32A, 32B) toward the outside thereof (apart from the through hole 5). In the former case, the outer peripheral side edge portion of the ring portion 31(31A, 31B) is in contact with the wafer, and in the latter case, the inner peripheral side edge of the ring portion 31(31A, 31B) is in contact with the wafer.

In the above-described embodiment, the tapered portion 33(33A, 33B) has the ridge line of a straight line shape in a front view, but the present invention is not limited thereto. For example, the ridgeline in the front view may be an upwardly convex arc-shaped tapered portion 33C (see fig. 15) or a downwardly concave arc-shaped tapered portion 33D (see fig. 16). The tapered portion may not be continuous, and may be a tapered portion 33E having a stepped shape in a front view (see fig. 17).

The alignment may be performed without the ID reading unit 208 and the ID reading. However, in this case, the ID reading unit 208 is installed in another location.

In the above-described embodiment, the case where two tables (tables 202a and 202b) are provided in the alignment apparatus 200 has been described as an example, but the present invention is not limited thereto. For example, three or more tables may be provided in the alignment apparatus. In this case, the number of ID reading units 208 is increased according to the number of tables to be added.

The cushion 1 of the above embodiment can be attached to a table even in an alignment apparatus including only one table. In this configuration, since the contact area between the wafer and the annular portion 31A of the pad 1 can be reduced, the adhesion of particles to the wafer can be suppressed. As with the above-described embodiment, it is also possible to achieve an easy attaching work of the cushion 1 to the table main body portion and an easy detaching work thereof from the table main body portion.

The case of using the laser sensors as the notch portion detection units 206a and 206b has been described as an example, but the present invention is not limited thereto, and a sensor such as a reflection sensor may be used.

The present invention is not limited to the above-described embodiments, and may be appropriately modified or improved. The materials, shapes, sizes, numerical values, forms, numbers, arrangement positions, and the like of the components in the above-described embodiments are arbitrary and are not limited as long as the present invention can be achieved.

Description of reference numerals

1 liner

2 main body part

3 holding part

3A first holding part

3B second holding part

5 through hole

31(31A, 31B) annular portion (examples of first and second annular portions)

32(32A, 32B) flange portion (examples of first and second flange portions)

33(33A, 33B) tapered portion

34(34A, 34B) seating surface

101 sorter

102(102a, 102b) wafer

103 conveying device (robot)

104 arm

105a, 105b load port

112 notched portion

200 alignment device

202a, 202b table

204a, 204b mobile unit

206a, 206b notch portion detecting unit

208ID reading unit

210 controller

291 notch

301 table body part

302 opening

303 channel

304 carrying the surface.