阅读说明：本技术 用于晶片的衬底处置装置 (Substrate handling apparatus for wafers ) 是由 A·格莱斯纳 M·艾布尔 H·厄茨林格 于 2020-07-30 设计创作，主要内容包括：本发明涉及一种用于晶片的衬底处置装置、一种用于晶片的衬底处置系统和一种用于衬底处置的方法。所述衬底处置装置包括：末端执行器,矫直环,及吸盘。所述吸盘布置在所述矫直环内。将至少所述矫直环可释放地附着到所述末端执行器。所述吸盘的第一部分可连接到真空供应,且所述吸盘的第二部分可通过由所述真空供应提供的减压附着到衬底。所述吸盘在常压状态下从所述矫直环突出。所述吸盘在减压状态下与所述矫直环处于同一水平上,在所述减压状态下,所述衬底由所述吸盘固持,使得所述矫直环接触所述衬底。(The present invention relates to a substrate handling apparatus for a wafer, a substrate handling system for a wafer and a method for substrate handling. The substrate handling device comprises: an end effector, a straightening ring, and a suction cup. The suction cup is arranged in the straightening ring. Releasably attaching at least the straightening ring to the end effector. A first portion of the chuck may be connected to a vacuum supply and a second portion of the chuck may be attached to a substrate by a reduced pressure provided by the vacuum supply. The suction cup protrudes from the straightening ring under normal pressure. The suction cup is on the same level as the straightening ring in a reduced pressure state, and the substrate is held by the suction cup in the reduced pressure state so that the straightening ring contacts the substrate.)

1. A substrate handling device (10) for a wafer, comprising:

-an end effector (11),

-a straightening ring (12), and

-a suction cup (13),

wherein the suction cup (13) is arranged within the straightening ring (12) and at least the straightening ring (12) is releasably attached to the end effector (11),

Wherein a first portion of the suction cup (13) is connectable to a vacuum supply and a second portion of the suction cup (13) is attachable to a substrate by a reduced pressure provided by the vacuum supply,

wherein the suction cup (13) protrudes from the straightening ring (12) under normal pressure, and

wherein the suction cup (13) is on the same level as the straightening ring (12) in a depressurized state in which the substrate is held by the suction cup (13) such that the straightening ring (12) contacts the substrate.

2. The substrate handling device (10) according to claim 1, wherein the suction cup (13) is also releasably attached to the end effector (11).

3. The substrate handling device (10) according to any of the preceding claims, wherein the straightening ring (12) surrounds the suction cup (13) and limits radial deformation of the suction cup (13).

4. The substrate handling device (10) according to any of the preceding claims, wherein said suction cups (13) hold said substrate in said reduced pressure state in a substantially horizontal or substantially vertical position with respect to the ground.

5. The substrate handling device (10) according to any of the preceding claims, wherein the straightening ring (12) at least partially straightens the non-planar substrate when the straightening ring (12) contacts the substrate and the substrate is non-planar.

6. The substrate handling device (10) according to any of the preceding claims, wherein in the atmospheric pressure state the suction cup (13) protrudes from the straightening ring (12) by a distance d, and wherein the ratio of distance d to the dimension s of the substrate is between 30: 1 to 800: 1, in the range between.

7. The substrate handling device (10) according to any of the preceding claims, wherein the outer circumference of the straightening ring (12) is larger than the outer circumference of the suction cup (13).

8. The substrate handling device (10) according to any of the preceding claims, wherein a substrate contact surface (14) of the suction cup (13) protrudes from the straightening ring (12) in the atmospheric pressure state.

9. The substrate handling device (10) according to any of the preceding claims, wherein the straightening ring (12) is made of a more rigid material than the chuck material of the chuck (13).

10. The substrate handling device (10) according to any of the preceding claims, further comprising a plurality of suction cups (13), and preferably three suction cups (13).

11. The substrate handling device (10) according to the preceding claim, further comprising a plurality of straightening rings (12), and preferably three straightening rings (12), each straightening ring surrounding one of the suction cups (13).

12. A substrate handling system for wafers comprising a substrate handling device (10) according to any of the preceding claims and a vacuum supply connected to a first part of a chuck (13) of the substrate handling device (10).

13. The substrate handling system of the preceding claim, further comprising at least one replacement straightening ring to replace a straightening ring (12) of the substrate handling device (10).

14. A method for substrate handling, comprising the steps of:

-providing a suction cup (13) arranged within the straightening ring (12),

wherein at least the straightening ring (12) is releasably attached to the end effector (11),

wherein a first part of the suction cup (13) is connected to a vacuum supply, and

wherein the suction cup (13) protrudes from the straightening ring (12) under normal pressure conditions,

-providing contact between a second part of the chuck (13) and the substrate, and

-providing a reduced pressure state by the vacuum supply such that the substrate is held by the chuck (13),

wherein the suction cup (13) is on the same level as the straightening ring (12) in the depressurized state such that the straightening ring (12) contacts the substrate.

15. The method according to the preceding claim, wherein the straightening ring (12) contacts the substrate and, in case the substrate is non-planar, at least partially straightens the substrate in the depressurized state.

Technical Field

The present invention relates to a substrate handling apparatus for a wafer, a substrate handling system for a wafer and a method for substrate handling. The invention relates in particular to single wafer handling for thin substrates. Thin substrates refer to substrates from a few hundred microns to under 100 microns.

Background

In the semiconductor and proximity industries (packaging, solar panels, etc.), wafer processing and in general substrate processing typically requires reliable handling of thin substrates. Reliable means for picking, placing or replacing substrates in a vertical or horizontal position from a storage cassette or for robotic handling in a processing tool without scratching, breaking, strongly bending or even cracking the substrates. Thin substrates refer to substrates from a few hundred microns to sometimes well below 100 microns.

The thin effect causes these substrates to often be very fragile and already bent, so no planar substrate is formed or displayed when held without a support structure. This natural occurrence of substrate bending, caused by stress in the material or simply gravity, is a major problem when attempting to handle thin wafers, especially when attempting to handle thin substrates with handling tools that hold the substrate in place by applying an amount of vacuum at one or more locations of the substrate.

When a sufficiently strong vacuum is applied so that the substrate does not fall off the moving handling device, the following occurs in currently existing systems: in addition to the already existing deformations, the substrate is also deformed by vacuum forces. This additional deformation leads in many cases to the fact that: the vacuum suction is lost and the substrate falls from the handling device or, in some cases, cracks and fractures due to additional deformation at the location where the vacuum force is applied.

WO 2015/134258 a1 discloses wafer handling end effectors and semiconductor manufacturing devices that include and/or are used with wafer handling end effectors. The end effector includes an end effector body and a plurality of wafer contact surfaces supported by the end effector body and configured to make at least partial face-to-face contact with a wafer. The end effector further includes a vacuum distribution manifold extending between a robot proximal end of the end effector body and the plurality of wafer contact surfaces. The end effector also includes a plurality of vacuum openings defined within the plurality of wafer contact surfaces and extending between the plurality of wafer contact surfaces and the vacuum distribution manifold. The end effector further includes a plurality of sealing structures, each of the sealing structures being associated with a respective one of the plurality of wafer contacting surfaces.

When a thin, already bent substrate is contacted by an end effector of, for example, WO 2015/134258 a1, the substrate remains bent or bent even more, since the washer is adjusting its deformation to the given bent state of the substrate. This deformation leads to the fact that vacuum suction is lost, the substrate falls off the handling device, and/or cracks.

Furthermore, there is a significant delay in releasing the wafer from the vacuum holding system when the vacuum is turned off. Since the substrate is in intimate contact with the wafer contact surface of the integrated vacuum source, it takes between hundreds of microseconds to a few seconds before the vacuum is weak enough to release the wafer. In large manufacturing operations that handle hundreds of thousands of wafers per day, this release delay results in significant processing and manufacturing delays.

Disclosure of Invention

It may therefore be desirable to provide an improved substrate handling device which allows for better handling, in particular thin substrates.

The problem of the present invention is solved by the subject matter of the independent claims, wherein further embodiments are incorporated in the dependent claims. It should be noted that the aspects of the invention described below are also applicable to a substrate handling device for a wafer, a substrate handling system for a wafer, and a method for substrate handling.

According to the present invention, a substrate handling device for a wafer is presented. The substrate handling device comprises:

-an end-effector which, when the end-effector is in the closed position,

-a straightening ring, and

-a suction cup.

The suction cup is arranged in the straightening ring. A first portion of the chuck may be connected to a vacuum supply via the end effector, and a second portion of the chuck may be attached to a substrate by a reduced pressure provided by the vacuum supply. The suction cup protrudes from the straightening ring under normal pressure. The suction cup is on the same level as the straightening ring in a reduced pressure state in which the substrate is held by the suction cup so that the straightening ring contacts the substrate.

The substrate handling device is configured to handle a substrate. The substrate to be handled may be a wafer. The substrate may be thin or ultra-thin, which is to be understood as a substrate having a thickness of from several hundred micrometers to under 100 micrometers, preferably 10 to 750 μm, and more preferably 20 to 100 μm. Substrates having this thickness are typically very fragile and have initially been bent, possibly due to gravity, stresses within the material, or the like. This means that thin substrates typically do not have a flat surface or form a flat surface when held without support.

The suction cup is arranged in the straightening ring. The suction cup may be arranged in the center of the straightening ring. The straightening ring may surround the suction cup. The straightening ring thereby constrains the suction cup. The straightening ring limits or prevents (radial) deformation of the chuck and does not allow deformation of the chuck according to a given bending state of the substrate. Thus, in the case of thin and generally non-planar substrates, vacuum suction is not lost, and such substrates are neither broken nor lost.

The straightening ring may be releasably attached to the end effector. The straightening ring may be removably or interchangeably connected to the end effector. In other words, the straightening ring may not be part of the end effector, not integrated in the end effector, not integral with the end effector. The straightening ring may not be fixedly or permanently connected to the end effector, but may be replaced or replaced with another straightening ring that is newer or has other properties, shapes, or sizes. Additionally or alternatively, the suction cup may be releasably attached to the end effector.

In embodiments, the straightening ring may be connected to the end effector directly or indirectly via a support element disposed between the end effector and the straightening ring. When mounted to the end effector or the support element, the straightening ring may provide a form fit, force fit, or threaded connection such that the straightening ring may be easily released, exchanged, or replaced.

In embodiments, the suction cup may be connected to the end effector directly or indirectly via a support element disposed between the end effector and the straightening ring. The suction cup may be attached to the end effector independently of the straightening ring so that removal of the straightening ring does not affect the suction cup. When mounted to the end effector or the support element, the suction cups may provide a form fit, force fit, or threaded connection so that the suction cups may be easily released, exchanged, or replaced.

During operation of the substrate handling device, the first portion of the chuck is connected to the vacuum supply and the second portion of the chuck is sucked to the substrate or wafer.

Under normal pressure or ambient pressure, the suction cup protrudes from the straightening ring. In particular, the substrate contacting surface of the suction cup may protrude from the straightening ring. In other words, the outer edge of the suction cup may initially extend a distance further away from the end effector body than the straightening ring.

The suction cup is at the same level as the straightening ring in the state of reduced pressure provided by the vacuum supply. In other words, the outer edge of the suction cup may reach the same height as the straightening ring. In the reduced pressure state, the straightening ring may contact the substrate, a reduced pressure or vacuum may be applied to the substrate surface, and the chuck may hold the substrate in place. The straightening ring provides a specific contact area (specific area profile) with the substrate and thereby provides a means for straightening also curved and/or otherwise deformed substrates. Thus, the curvature of the substrate caused by the reduced pressure or vacuum, and if applicable, the initial or pre-existing curvature of the substrate, may also be significantly reduced.

The substrate handling device for wafers according to the invention thus allows better handling of thin substrates. It significantly improves the performance and functionality of handling fragile substrates. The disc-shaped straightening ring is arranged around the suction cup and acts as a vacuum suction gasket. The straightening ring thereby limits or prevents (radial) deformation of the suction cup and does not allow deformation of the suction cup according to a given bending state of the substrate. Thus, in the case of thin and generally non-planar substrates, vacuum suction is not lost, and such substrates are neither broken nor lost. Thereby, it is possible to safely move thin and/or curved substrates into and out of very small gaps (such as transport cassettes or special processing chambers or equipment or the like) having dimensions close to the thickness of the substrate. In other words, thin and even warped, curved, bent, and/or otherwise non-planar wafers/substrates may be handled, held, transferred, and/or the like. Such substrates can be straightened or flattened at handling to allow movement also with reduced space requirements.

In an embodiment, the rate of protrusion or release speed of the chuck from the straightening ring may be adjusted by controlling the pressure or vacuum applied in the chuck to release the substrate from the chuck in a controlled manner. Thus, the reduced pressure or vacuum may be gradually turned off or reduced. Thus, the substrate may be released at a predetermined point in time. Releasing the chuck and thus the substrate from the straightening ring can be done at all speeds from immediate to relatively slow. It may be pop-up or it may be done carefully and smoothly. In some cases, the main advantage may be that the release of the substrate may be achieved with zero uncontrolled delay. There may also be a microsecond to second intentional delay in releasing the substrate before the reduced pressure or vacuum is intentionally weakened sufficiently to release the substrate. When the substrate is released again, the reduced pressure or vacuum may be turned off or gradually reduced. Thus, the suction cup lifts, moves, expands back to its original position, and again extends a distance further away from the end effector body than the straightening ring. Thus, the substrate is pushed off the straightening ring and can be released from the chuck at a predetermined moment without any difficulty or delay in release. In other words, the release of the substrate takes place instantaneously at a moment determined according to need. Thereby, substrate handling and substrate handling time is significantly improved and the risk of wafer breakage by delaying substrate release is significantly eliminated.

In an embodiment, the straightening ring at least partially straightens a non-planar substrate when the straightening ring contacts the substrate and the substrate is non-planar. The straightening ring may not only contact the substrate but may also carefully force the straightening of a substrate that has been initially bent or curved. The straightening may depend on the vacuum strength and/or the size and/or shape of the straightening ring. In other words, the straightening effect on a curved substrate can be adjusted by the strength of the applied vacuum or reduced pressure and/or the size and/or shape of the straightening ring. In embodiments, the suction cup may retract with the strength of the applied vacuum or reduced pressure. Therefore, flattening of the bent substrate can be facilitated without damaging the (ultra) thin substrate.

The substrate may comprise a conductor plate, a semiconductor substrate, a thin film substrate, a substantially plate-like, metallic or metalized workpiece, or the like. Vacuum or reduced pressure may be supplied to the substrate, and preferably to the backside of the substrate, through the chuck. The back side of the substrate is the side of the substrate that does not have structures such as electronic components or that has smaller such structures (if applicable). However, the front side of the substrate, which is the side with the (more) structure or electronic component, may also be contacted. The structure or electronic component may be protected from contact damage by, for example, a passivation layer deposited on top of the structure or electronic component. A vacuum outlet may be positioned below the straightening ring, and preferably at a distance from the straightening ring.

The end effector may include a plurality of substrate handling surface contacts and hold the substrate or wafer on the end effector with a vacuum or reduced pressure. The strength of the applied vacuum or reduced pressure can be adjusted depending on the requirements of different substrates and their bending profiles. Furthermore, the shape, size and material of the straightening ring can be adjusted according to the requirements of different substrates and their bending profiles. As does the suction cup.

The suction cup may be resilient, soft and/or flexible. It may be made of a resilient, soft and/or flexible material. It may be made of a material that does not contaminate the substrate. The suction cup may be made of silicone.

The straightening ring or disc may be implemented in a circular shape or a non-circular shape, which may be circular, oval or square or any other shape that may provide a beneficial effect. The straightening ring may be hard, stiff and/or rigid. In an embodiment, the straightening ring is made of a material that is more rigid than the material of the suction cup. The straightening ring may be made of ceramic (e.g. SiC) or plastic (e.g. PEEK).

In an embodiment, the substrate handling device further comprises a plurality of suction cups. Preferably, the substrate handling device comprises two to twenty, and more preferably two, three or four suction cups.

In an embodiment, the substrate handling device further comprises a plurality of straightening rings, each straightening ring surrounding one of the chucks. Preferably, the substrate handling device comprises two to twenty, and more preferably two, three or four straightening rings, each surrounding one of the suction cups. The substrate handling device preferably comprises an equal number of suction cups and straightening rings.

In embodiments, the chuck may hold the substrate in a depressurized state at all positions or at several selected positions or at any position relative to the ground. Preferably, the substrate handling device and the suction cup may hold the substrate in the reduced pressure state in a substantially horizontal or vertical position. When a substrate and a substrate handling device are positioned in a horizontally extending direction, the substrate may be placed or on top of the chuck of the substrate handling device. The substrate may also be mounted below the chuck when the handling device is inverted to pick the substrate from a location where the substrate had been previously placed. When a substrate and a substrate handling device are positioned in a vertically extending direction, such as within a storage or transport cassette, the substrate may be placed or positioned in parallel and vertically extending proximity to the chuck. Due to the reduced pressure or vacuum, the chuck can be attached to the substrate in a horizontal or vertical position and pull the substrate closer until the substrate touches the straightening ring.

In an embodiment, the outer circumference of the straightening ring is larger than the outer circumference of the suction cup. This is to be understood as meaning that the straightening ring can extend radially above the suction cup.

In an embodiment, the suction cup protrudes a distance from the straightening ring under normal pressure conditions. The ratio of the distance to the size of the substrate may be in the range of 30: 1 to 800:1, and preferably in the range of 100: 1 to 600: 1, in the above range. In other words, the suction cup may extend axially above the straightening ring under normal pressure conditions. In contrast, the suction cup may be at the same level as the straightening ring in a depressurized state.

According to the invention, a substrate handling system for a wafer is also presented. The substrate handling system comprises a substrate handling device and a vacuum supply as described herein. The vacuum supply is connected to a first portion of a chuck of the substrate handling device.

In an embodiment, the substrate handling system further comprises at least one replacement straightening ring to replace a straightening ring of the substrate handling device.

According to the invention, a method for substrate handling is also proposed. The substrate handling method comprises the following steps, not necessarily in this order:

a) Suction cups are provided which are arranged inside the straightening ring.

Releasably attaching at least the straightening ring to an end effector. Connecting a first portion of the suction cup to a vacuum supply via the end effector. The suction cup protrudes from the straightening ring under normal pressure.

b) Providing contact between the second portion of the chuck and the substrate.

c) Providing a reduced pressure state by the vacuum supply such that the substrate is held by the chuck.

The suction cup is on the same level as the straightening ring in the reduced pressure state so that the straightening ring contacts the substrate.

The straightening ring contacts the substrate in the reduced pressure state and, in the event the substrate is non-planar, may at least partially straighten the substrate.

In particular, the apparatus, systems and methods are applicable to the processing of structured semiconductor substrates, conductor plates and thin film substrates, but also to the processing of planar metal and metallized substrates across their entire surface. According to the present invention, the apparatus, system and method can also be used to produce large surface photovoltaic panels or large monitor panels for solar power generation.

It shall be understood that the system, the apparatus and the method for substrate handling of wafers according to the independent claims have similar and/or identical preferred embodiments, in particular as defined in the dependent claims. It shall further be understood that preferred embodiments of the present invention may also be any combination of the dependent claims with the respective independent claims.

These and other aspects of the invention will be apparent from and elucidated with reference to the embodiments described hereinafter.

Drawings

Exemplary embodiments of the invention will be described below with reference to the accompanying drawings:

fig. 1 shows schematically and exemplarily an embodiment of a substrate handling device for a wafer according to the present invention.

Detailed Description

Fig. 1 shows schematically and exemplarily an embodiment of a substrate handling device 10 for a wafer according to the present invention. The substrate handling device 10 is configured to handle thin or ultra-thin substrates or wafers (not shown), which may have a thickness of about 20-500 μm. Substrates with such thicknesses are typically very fragile, have been bent initially, and do not have flat surfaces.

The substrate handling device 10 includes:

-an end-effector 11 for performing a surgical operation,

a straightening ring 12, and

-a suction cup 13.

The end effector 11 includes a plurality of suction cups 13 (only one shown), which suction cups 13 contact the substrate and utilize a vacuum or reduced pressure to hold the substrate on the suction cups 13 or the end effector 11.

The straightening ring 12 is more rigid than the suction cups 13, said suction cups 13 being softer and more resilient than the straightening ring 12. The straightening ring 12 is releasably attached to the end effector 11. The outer circumference of the straightening ring 12 is larger than the outer circumference of the suction cup 13. This can be understood as the straightening ring 12 extending radially above the suction cup 13.

The suction cup 13 is arranged inside the straightening ring 12 and in the centre of the straightening ring 12. The straightening ring 12 surrounds the suction cup 13 and thereby constrains the suction cup 13. It restricts or prevents radial deformation of the suction cup 13, and does not allow the suction cup 13 as a gasket to deform according to a given bent state of the thin substrate. Thus, in the case of thin and generally non-planar substrates, vacuum suction is not lost, and such substrates are neither broken nor lost.

A first portion of the chuck 13 is connected to a vacuum supply via a vacuum outlet 15 of the end effector 11, and a second portion of the chuck 13 may be attached to the substrate by a reduced pressure provided by the vacuum supply. During operation of the substrate handling device 10, the vacuum supply is activated and the second part of the chuck 13 is sucked to the substrate. In fig. 1, the substrate will be in a horizontal extension on top of the chuck 13.

As shown, the suction cup 13 protrudes from the straightening ring 12 under normal pressure conditions. In particular, the substrate contact surface 14 or outer edge of the suction cup 13 protrudes axially from the straightening ring 12. It extends a distance further away from the end effector body than the straightening ring 12. The suction cup 13 will be at the same level as the straightening ring 12 in a depressurized state (not shown), wherein the straightening ring 12 contacts the substrate so that the substrate is held by the suction cup 13. The outer edge of the suction cup 13 will reach the same height as the straightening ring 12 and will thus straighten a potentially curved substrate.

When the substrate should be released, the reduced pressure or vacuum will be turned off or gradually reduced. Thus, the suction cup 13 will be lifted back to its original position and extend further away from the end effector body and the straightening ring 12 again. Thus, the substrate will be pushed off the straightening ring and then released from the chuck 13 at a predetermined moment.

The straightening ring 12 and suction cup 13 are releasably, removably and interchangeably attached to the end effector 11. It can be exchanged or replaced by another straightening ring 12 or suction cup 13, said other straightening ring 12 or suction cup 13 being renewed or having other properties, shapes or sizes.

It must be noted that embodiments of the invention are described with reference to different subject matters. In particular, some embodiments are described with reference to method type claims, whereas other embodiments are described with reference to apparatus type claims. However, a person skilled in the art will gather from the above and the following description that, unless other notified, in addition to any combination of features belonging to one type of subject matter also any combination between features relating to different subject matters is considered to be disclosed. However, all functions may be combined, providing more synergistic effects than a simple addition of functions.

While the invention has been illustrated and described in detail in the drawings and foregoing description, such illustration and description are to be considered illustrative or exemplary and not restrictive. The invention is not limited to the disclosed embodiments. Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure, and the appended claims.

In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality. A single processor or other unit may fulfill the functions of several items recited in the claims. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. Any reference signs in the claims shall not be construed as limiting the scope.