Substrate separation device

Abstract

Provided is a substrate separation device capable of suppressing intrusion of liquid into a portion between a chuck and a substrate. A substrate separation device according to an embodiment of the present invention comprises: a first chuck that attracts and holds one surface of a bonded substrate resulting from bonding of a pair of substrates; a second chuck that holds the other surface of the bonded substrate; an exhaust unit that is connected to the first chuck; a drive unit that rotates the first chuck and the second chuck; and a nozzle that ejects liquid to the lateral surface of the bonded substrate. The first chuck has a first recess connected to the exhaust unit, and a second recess not connected to the exhaust unit. The first recess is open in a first surface of the first chuck on the bonded substrate side. The second recess is open in a region in the first surface between a region in which the first recess is open and the circumferential edge of the first surface.

Description

Substrate separation device

[0001] SUMMARY OF THE INVENTION An embodiment of the present invention relates to a substrate separation apparatus.

[0002] For example, a technique has been proposed in which a pair of substrates are bonded together, the bonded pair of substrates are separated, and a layer formed on one substrate is transferred to the other substrate. Such a technique is used, for example, in the manufacture of semiconductor devices having a three-dimensional structure.

[0003] In this case, a liquid ejection device may be used to separate the bonded substrates. For example, the bonded substrates are sandwiched between a pair of chucks, and the bonded substrates are rotated by rotating the chucks. High-pressure liquid is ejected onto the sides of the rotating substrates to separate the bonded substrates. In this case, the bonded substrates are vacuum-adsorbed to the chucks. This prevents the bonded substrates from shifting position.

[0004] However, liquid sprayed onto the side of the bonded substrates may infiltrate between the chuck and the substrate. Because the substrates are vacuum-adsorbed to the chuck, if liquid infiltrates between the chuck and the substrate, the force holding the substrates weakens, and the bonded substrates may become misaligned. If the bonded substrates become misaligned, uniform separation may be hindered, reducing separation efficiency and possibly damaging the substrates. Therefore, there has been a need for a substrate separation device that can prevent liquid from infiltrating between the chuck and the substrate.

[0005] Japanese Patent Application Publication No. 11-005064

[0006] An object of the present invention is to provide a substrate separating apparatus that can prevent liquid from entering between the chuck and the substrate.

[0007] The substrate separating device according to the embodiment includes a first chuck for suction-holding one side of a bonded substrate formed by bonding a pair of substrates together, a second chuck for holding the other side of the bonded substrate, an exhaust unit connected to the first chuck, a drive unit for rotating the first chuck and the second chuck, and a nozzle for spraying liquid onto the side of the bonded substrate. The first chuck has a first recess connected to the exhaust unit and a second recess not connected to the exhaust unit. The first recess is open to a first surface of the first chuck facing the bonded substrate. The second recess is open to a region of the first surface between the region where the first recess is open and the periphery of the first surface.

[0008] According to an embodiment of the present invention, a substrate separating apparatus is provided that can prevent liquid from entering between a chuck and a substrate.

[0009] 1 is a schematic diagram illustrating a substrate separating apparatus according to the present embodiment. FIG. 2 is a schematic perspective view illustrating the configuration of a chuck. FIG. 3 is a schematic cross-sectional view of the chuck in FIG. 2 taken along line A-A. FIG. 4 is a schematic perspective view illustrating the configuration of a chuck according to another embodiment. FIG. 5 is a schematic cross-sectional view of the chuck in FIG. 4 taken along line B-B. (A) and (B) are schematic cross-sectional views illustrating the configuration of a chuck according to another embodiment. (A) to (H) are schematic views illustrating the operation of a substrate separating apparatus. FIG. 6 is a flowchart illustrating a procedure for separating bonded substrates. FIG. 7 is a schematic view illustrating the separation of bonded substrates. FIG. 8 is a schematic view illustrating the separation of bonded substrates.

[0010] Hereinafter, embodiments will be illustrated with reference to the drawings. In the drawings, like components are designated by like reference numerals and detailed descriptions thereof will be omitted where appropriate.

[0011] The bonded substrate 100 to be separated by the substrate separating apparatus 1 according to this embodiment includes, for example, a substrate 101 and a substrate 102 bonded to one side of the substrate 101. The substrates 101 and 102 may be, for example, semiconductor wafers. A porous layer is provided on one side of the substrate 101, and a single-crystal Si layer is provided on the porous layer. A single-crystal Si layer is provided on one side of the substrate 102. An insulating layer is provided on the single-crystal Si layer of the substrate 101 or on the single-crystal Si layer of the substrate 102. The substrates 101 and 102 are bonded together via the insulating layer. However, the bonded substrate 100 is not limited to the example shown. The bonded substrate 100 may be any substrate in which the substrate 101 and the substrate 102 are bonded together via a layer such as an insulating layer.

[0012] 1 is a schematic diagram illustrating a substrate separating apparatus 1 according to the present embodiment. As shown in FIG. 1, the substrate separating apparatus 1 includes, for example, a base 10, a holding unit 20, a positioning unit 30, a separating unit 40, and a controller 50.

[0013] The base 10 can be provided, for example, at the installation location of the substrate separating apparatus 1. A holding unit 20, a positioning unit 30, and a separating unit 40 can be provided on one surface of the base 10. In addition, a base 10a can be provided opposite the base 10. A chuck 21 (corresponding to an example of a second chuck), a support unit 22, a chuck 23 (corresponding to an example of a first chuck), a drive unit 24, and a moving unit 25, which will be described later, are provided between the base 10a and the base 10. The base 10a can be integrated with the base 10, for example, via a stand (not shown).

[0014] The holding unit 20 includes, for example, a chuck 21 , a support unit 22 , a chuck 23 , a drive unit 24 , a moving unit 25 , and an exhaust unit 26 .

[0015] The chuck 21 is provided on the substrate 101 side of the bonded substrate 100. The chuck 21 suction-holds one surface of the bonded substrate 100, which is made up of a pair of substrates 101 and 102 bonded together. The chuck 21 can be, for example, a vacuum chuck. The configuration of the chuck 21 will be described in detail later.

[0016] The support portion 22 rotatably supports the chuck 21. The support portion 22 is provided on, for example, the base 10a. The support portion 22 has, for example, a rotation shaft 22a and a rotation mechanism 22b.

[0017] The rotation shaft 22a extends along the rotation center axis 1a of the substrate separating apparatus 1. A chuck 21 is provided on one end side of the rotation shaft 22a. The other end side of the rotation shaft 22a is connected to a rotation mechanism 22b.

[0018] The rotation mechanism 22b rotates the chuck 21 in synchronization with the chuck 23, which will be described later. The rotation mechanism 22b has a synchronization transmission member such as a timing belt or a timing pulley. The synchronization transmission member is connected to the rotation shaft 22a on which the chuck 21 is provided and to a drive unit 24, which will be described later. In this manner, the drive unit 24 can rotate the chuck 21 simultaneously with the chuck 23, which will be described later, and at the same rotation speed. This makes it possible to simplify the configuration of the rotation mechanism 22b and the control software, and ultimately to reduce the manufacturing cost of the substrate separation apparatus 1.

[0019] The chuck 23 is provided on the substrate 102 side of the bonded substrate 100. The chuck 23 suction-holds the other surface of the bonded substrate 100 (the surface opposite to the surface on the substrate 101 side). The chuck 23 can be, for example, a vacuum chuck. In this case, as shown in FIG. 1 , the chuck 23 suction-holds the surface of the bonded substrate 100 on the lower side in the direction of gravity. Therefore, when separating the bonded substrate 100 into the substrate 101 and the substrate 102, the chuck 23 holds the substrate 102 on the reference side. The configuration of the chuck 23 will be described in detail later.

[0020] The drive unit 24 rotates the chuck 23 and also rotates the chuck 21 in synchronization with the chuck 23 via the rotation mechanism 22b and the rotation shaft 22a. Therefore, the drive unit 24 can rotate the bonded substrate 100 gripped by the chuck 23 and the chuck 21. The drive unit 24 can also control the rotation speed of the bonded substrate 100 and control the start and stop of the rotation. The drive unit 24 can include, for example, a control motor such as a servo motor and a rotation shaft 24a. The chuck 23 is provided on one end side of the rotation shaft 24a. The other end side of the rotation shaft 24a is connected to the control motor via a transmission member or the like.

[0021] 1, the central axis of the rotation shaft 22a, the central axis of the chuck 21, the central axis of the chuck 23, and the central axis of the rotation shaft 24a overlap with the rotation central axis 1a. That is, these central axes are arranged to be coaxial. Therefore, when the bonded substrate 100 is rotated, it is possible to prevent the relative positions of the chuck 21 and the chuck 23 from shifting in the direction perpendicular to the rotation central axis 1a.

[0022] The moving unit 25 moves the driving unit 24 in a direction along the rotation central axis 1a. The moving unit 25, for example, raises and lowers the driving unit 24. Since the driving unit 24 (rotation axis 24a) is provided with a chuck 23, the distance between the chuck 23 and the chuck 21 in the direction along the rotation central axis 1a can be changed by moving the driving unit 24 with the moving unit 25. Therefore, the moving unit 25 can grip and release the bonded substrate 100 with the chuck 23 and the chuck 21. The moving unit 25 can have, for example, a driving mechanism such as an air cylinder or a hydraulic cylinder, and a guide mechanism for moving the driving unit 24 linearly.

[0023] The exhaust unit 26 is connected to the chuck 21 via a piping member such as a rotary joint provided on the support unit 22. The exhaust unit 26 performs suction so that the pressure between the chuck 21 and the bonded substrate 100 (substrate 101) becomes negative. The exhaust unit 26 is also connected to the chuck 23 via a piping member such as a rotary joint provided on the drive unit 24. The exhaust unit 26 performs suction so that the pressure between the chuck 23 and the bonded substrate 100 (substrate 102) becomes negative. The exhaust unit 26 has an exhaust device such as a vacuum pump.

[0024] Furthermore, a gas-liquid separator may be provided between the chucks 21 and 23 and an exhaust device such as a vacuum pump.

[0025] Furthermore, a pressure control device can be provided at least between the chuck 21 and the gas-liquid separator and between the chuck 23 and the gas-liquid separator. If a pressure control device is provided, it becomes possible to control the suction forces of the chucks 21 and 23.

[0026] The positioning unit 30 positions the bonded substrate 100 in a direction perpendicular to the rotation central axis 1a. The positioning unit 30 adjusts the position of the bonded substrate 100 so that the center of the bonded substrate 100 overlaps with the rotation central axis 1a.

[0027] The positioning portion 30 has, for example, a pin 31, an arm 32, a moving portion 33, a moving portion 34, a guide 35, and an absorbing portion 36. A plurality of sets of the pin 31, the arm 32, the moving portion 33, the guide 35, and the absorbing portion 36 can be provided.

[0028] The pin 31 has, for example, a columnar shape and extends in a direction along the rotation central axis 1a. The side surface of the pin 31 contacts the side surface of the laminated substrate 100. The pin 31 can be provided, for example, at the upper end of the arm 32. When viewed from the direction along the rotation central axis 1a, the multiple pins 31 can be provided at positions that are rotationally symmetric with respect to the rotation central axis 1a.

[0029] The arm 32 is plate-shaped and extends in a direction along the rotational axis 1a. The moving unit 33 moves the arm 32 in the direction along the rotational axis 1a. For example, the moving unit 33 raises and lowers the arm 32. The moving unit 33 has a driving mechanism such as an air cylinder or a hydraulic cylinder.

[0030] One moving unit 34 can be provided for each of the multiple arms 32. The moving unit 34 has, for example, a link mechanism or a cam mechanism, and simultaneously changes the positions of the multiple arms 32 in a direction perpendicular to the rotation center axis 1a. For example, the moving unit 34 moves the multiple arms 32 toward the rotation center axis 1a, causing the multiple pins 31 to press the side surfaces of the bonded substrate 100 toward the rotation center axis 1a. The multiple pins 31 press the side surfaces of the bonded substrate 100 toward the rotation center axis 1a, causing the center of the bonded substrate 100 to overlap the rotation center axis 1a. In other words, the bonded substrate 100 is positioned. Furthermore, for example, the moving unit 34 moves the multiple arms 32 in a direction away from the rotation center axis 1a, thereby separating the multiple pins 31 from the side surfaces of the bonded substrate 100.

[0031] The guides 35 are provided between each of the multiple arms 32 and the moving unit 34. The guides 35 guide the movement of the arms 32 in the direction along the rotation central axis 1a. The guides 35 may be, for example, linear guides. If the guides 35 are provided, the relative positions between the arms 32 and the moving unit 34 in the direction along the rotation central axis 1a can be changed as desired.

[0032] The absorbing portion 36 is provided between the arm 32 and the moving portion 33. The absorbing portion 36 absorbs changes in position between the arm 32 and the moving portion 33 in a direction perpendicular to the rotation center axis 1 a. The absorbing portion 36 may include an elastic body such as rubber or a spring. If the absorbing portion 36 is provided, the moving portion 34 can absorb the amount of misalignment even if the position between the moving portion 33 and the arm 32 is misaligned in the direction perpendicular to the rotation center axis 1 a.

[0033] The separating unit 40 sprays a high-pressure liquid 40a onto the side surface of the rotating bonded substrate 100 to separate the bonded substrate 100 into the substrate 101 and the substrate 102. The liquid 40a is sprayed toward a layer (e.g., a porous layer or a single-crystal Si layer) provided between the substrate 101 and the substrate 102. The liquid 40a can be, for example, water such as ultrapure water. When the liquid 40a is water, the separating unit 40 can be a so-called water jet device.

[0034] The separation unit 40 includes, for example, a nozzle 41, a liquid supply unit 42, and a moving unit 43. The nozzle 41 is cylindrical and has an injection port 41a at one end. The diameter of the injection port 41a is, for example, about 0.1 mm to 1 mm. The thickness of the end of the nozzle 41 where the injection port 41a is provided is, for example, about 1 cm to 5 cm. By setting the thickness of the end of the nozzle 41 in this manner, damage to the nozzle 41 can be suppressed even when the liquid 40a is injected at high pressure. In the direction along the rotation central axis 1a, the central axis of the injection port 41a of the nozzle 41 is located between the substrate 101 and the substrate 102. Furthermore, the central axis of the injection port 41a of the nozzle 41 can be, for example, approximately parallel to the surface 23b (corresponding to an example of the first surface) of the chuck 23 facing the bonded substrate 100.

[0035] The liquid supply unit 42 supplies high-pressure liquid 40a to the nozzle 41. The pressure of the liquid 40a is, for example, approximately 15 MPa to 90 MPa. The flow rate of the liquid 40a is approximately 60 mL / min to 150 mL / min. The liquid supply unit 42 is connected, for example, via high-pressure piping, to the end of the nozzle 41 opposite the end where the injection port 41a is provided. The liquid supply unit 42 may be provided with, for example, a tank that stores the liquid 40a, a high-pressure pump that supplies the liquid 40a stored in the tank to the nozzle 41, a flow control valve that controls the flow rate and pressure of the liquid 40a supplied to the nozzle 41, and a switching valve that switches between supplying and stopping the supply of the liquid 40a.

[0036] The moving unit 43 moves the position of the nozzle 41 (ejection port 41a) in a plane perpendicular to the rotation center axis 1a. The moving unit 43 moves the position of the nozzle 41 (ejection port 41a), for example, in a direction along a tangent to the periphery of the bonded substrate 100 and in a direction toward the central axis (rotation center axis 1a) of the bonded substrate 100. The moving unit 43 can be, for example, an XY table or a robot capable of control along two or more axes. The moving unit 43 can be provided on the base 10 via, for example, a stand 43a.

[0037] The controller 50 includes, for example, a calculation unit such as a CPU (Central Processing Unit) and a storage unit such as a memory. The controller 50 is, for example, a computer. The controller 50 controls the operation of each element provided in the substrate separating apparatus 1 based on a control program stored in the storage unit.

[0038] Next, the configurations of the chuck 21 and the chuck 23 will be further described. The configurations of the chuck 21 and the chuck 23 can be the same or different. In the following, a case will be described in which the chuck 21 and the chuck 23 have the same configuration. In this case, as described above, the chuck 23 holds the substrate 102, which serves as the reference side located on the lower side in the direction of gravity during separation processing. Therefore, the following description will mainly focus on the chuck 23.

[0039] Fig. 2 is a schematic perspective view illustrating the configuration of the chuck 23. Fig. 3 is a schematic cross-sectional view of the chuck 23 in Fig. 2 taken along line A-A. As shown in Figs. 2 and 3, the chuck 23 has a plate-like shape. When viewed from a direction along the central axis 23a of the chuck 23, the shape of the chuck 23 can be, for example, circular. The dimension of the chuck 23 in a direction perpendicular to the central axis 23a can be smaller than the dimension of the bonded substrate 100 (see Fig. 1).

[0040] The surface 23b of the chuck 23 facing the bonded substrate 100 can be a flat surface. The chuck 23 has at least one hole 23c opening on the surface 23b. The chuck 23 illustrated in FIGS. 2 and 3 has one hole 23c located at the center axis 23a and four holes 23c located at positions rotationally symmetrical about the center axis 23a. The number and arrangement of the holes 23c are not limited to those illustrated, and can be changed as appropriate depending on the size of the bonded substrate 100, etc. The hole 23c is connected to the exhaust unit 26, for example, via a piping member such as a rotary joint provided in the drive unit 24.

[0041] Furthermore, at least one recess 23d (corresponding to an example of a first recess) can be provided on the surface 23b. In this case, if multiple recesses 23d are provided, the suction force can be increased. The recess 23d is open to the surface 23b. The recess 23d is not open to the side of the chuck 23 facing the surface 23b. The recess 23d is connected to the hole 23c. The recess 23d is connected to the exhaust section 26 via the hole 23c. The recess 23d functions as a suction groove that suctions the bonded substrate 100. When viewed from a direction along the central axis 23a, the outline of the outer edge of the recess 23d can be similar to the outline of the periphery of the surface 23b. For example, in the case of the chuck 23 illustrated in FIG. 2, when viewed from a direction along the central axis 23a, the outline of the outer edge of the recess 23d can be circular. This makes it easier to uniform the suction force around the central axis 23a.

[0042] Furthermore, when multiple recesses 23d are provided, at least one recess 23d1 can be provided to connect the recesses 23d to one another. The recess 23d1 can be open to the surface 23b. If the recess 23d1 is provided, it becomes easy to connect the multiple recesses 23d to the hole 23c. Furthermore, if the recess 23d1 is open to the surface 23b, the recess 23d1 can function as a suction groove. This can increase the suction force.

[0043] Furthermore, when multiple recesses 23d1 are provided, the multiple recesses 23d1 can be provided at positions that are rotationally symmetrical about the central axis 23a. In this way, it is easy to make the suction force around the central axis 23a uniform. Furthermore, although Fig. 2 illustrates an example in which at least one end of the recess 23d1 directly communicates with the hole 23c, both ends of the recess 23d1 may communicate with the recess 23d.

[0044] The dimensions, number, arrangement, etc. of the recesses 23d, the recesses 23d1, and the holes 23c can be changed as appropriate depending on the dimensions of the surface 23b of the chuck 23, the required holding force, etc. These can be determined as appropriate by, for example, conducting experiments or simulations.

[0045] There are no particular limitations on the material of the chuck 23 as long as it has chemical and physical resistance to the sprayed liquid 40a. The material of the chuck 23 can be, for example, a metal such as stainless steel.

[0046] Here, the liquid 40a sprayed from the separation unit 40 may seep between the chuck 23 and the bonded substrate 100 (substrate 102). The liquid 40a that has reached at least one of the recess 23d and the recess 23d1 can be discharged by, for example, a gas-liquid separator provided in the exhaust unit 26.

[0047] However, even if the gas-liquid separator can protect an exhaust device such as a vacuum pump provided in the exhaust section 26, if the liquid 40a enters at least one of the recesses 23d, 23d1, and the hole 23c, the force (adsorption force) holding the bonded substrate 100 may decrease. If the force holding the bonded substrate 100 decreases, the position of the bonded substrate 100 with respect to the rotation center axis 1a may shift. If the position of the bonded substrate 100 shifts, uniform separation may be hindered, reducing separation efficiency, or at least one of the substrates 101 and 102 may be damaged.

[0048] 2 and 3, the chuck 23 is provided with at least one recess 23e (corresponding to an example of a second recess). The recess 23e is open to the surface 23b. The recess 23e can be provided near the periphery of the surface 23b. For example, the recess 23e is open to a region of the surface 23b between the region where the recess 23d, the recess 23d1, and the hole 23c are open and the periphery of the surface 23b. The recess 23e is not in communication with the recess 23d, the recess 23d1, and the hole 23c.

[0049] As shown in Fig. 2, the recess 23e has, for example, a frame shape and surrounds the area where the recess 23d, the recess 23d1, and the hole 23c are open. The recess 23e extends, for example, along the periphery of the surface 23b. In this case, the outline of the outer edge of the recess 23e when viewed from the direction along the central axis 23a can be similar to the outline of the periphery of the surface 23b. For example, in the case of the chuck 23 illustrated in Fig. 2, the outline of the outer edge of the recess 23e when viewed from the direction along the central axis 23a can be circular.

[0050] When a plurality of recesses 23e are provided, the plurality of recesses 23e may be arranged in a direction perpendicular to the central axis 23a. In this case, the plurality of recesses 23e may be provided concentrically around the central axis 23a.

[0051] If the recess 23e is provided near the periphery of the surface 23b, even if the liquid 40a penetrates between the chuck 23 and the bonded substrate 100 (substrate 102), the infiltrating liquid 40a can be captured by the recess 23e. Therefore, even if the liquid 40a penetrates between the holding unit 20 (chuck 23) and the bonded substrate 100 (substrate 102), the infiltrating liquid 40a can be prevented from reaching the recess 23d, the recess 23d1, and the hole 23c. If the infiltrating liquid 40a can be prevented from reaching the recess 23d, the recess 23d1, and the hole 23c, a decrease in the force (adsorption force) holding the bonded substrate 100 can be prevented. As a result, a misalignment of the bonded substrate 100 relative to the rotation center axis 1a can be prevented, which would hinder uniform separation, reduce separation efficiency, or cause damage to at least one of the substrates 101 and 102.

[0052] Furthermore, when the liquid 40a is sprayed by the liquid supply unit 42, the bonded substrate 100 is rotating. Therefore, the liquid 40a captured by the recess 23e is discharged to the outside of the bonded substrate 100 by centrifugal force. This further prevents the liquid 40a from reaching the recess 23d, the recess 23d1, and the hole 23c. In this case, for example, the distance between the recess 23e and the periphery of the surface 23b can be made shorter than the distance between the recess 23e and the recess 23d. In this way, it becomes easier to discharge the liquid 40a captured in the recess 23e to the outside of the chuck 23.

[0053] It is also possible to provide a plurality of recesses aligned along the periphery of surface 23b. This configuration also prevents infiltrating liquid 40a from reaching recesses 23d, 23d1, and holes 23c. However, if recess 23e is formed as a frame extending along the periphery of surface 23b, it is possible to more reliably prevent liquid 40a from reaching the regions where recesses 23d, 23d1, and holes 23c are provided.

[0054] The dimensions (width and depth), arrangement, number, etc. of the recesses 23e can be changed as appropriate depending on the pressure and flow rate of the ejected liquid 40a, the required holding power (adsorption power), etc. For example, these can be determined as appropriate by conducting experiments or simulations.

[0055] Although the configuration of the chuck 23 has been exemplified above, the configuration of the chuck 21 can be similar. For example, the chuck 21 can have a recess 23d (corresponding to an example of a third recess), a recess 23d1, and a hole 23c connected to the exhaust unit 26, and a recess 23e (corresponding to an example of a fourth recess). The recess 23d opens on the surface of the chuck 21 facing the bonded substrate 100 (corresponding to an example of a second surface). The recess 23e opens in a region of the surface of the chuck 21 facing the bonded substrate 100, between the region where the recess 23d, the recess 23d1, and the hole 23c open and the periphery of the surface. The recess 23e can also be frame-shaped and surround the region where the recess 23d, the recess 23d1, and the hole 23c open. The recess 23e can also extend along the periphery of the surface of the chuck 21 facing the bonded substrate 100. Furthermore, the distance between the recess 23e and the periphery of the surface of the chuck 21 facing the bonded substrate 100 can be made shorter than the distance between the recess 23e and the recess 23d.

[0056] However, the configuration of the chuck 21 may be different from the configuration of the chuck 23. For example, the outer dimensions of the chuck 21, and the dimensions, number, and arrangement of the recesses 23d, 23d1, holes 23c, and recesses 23e may be different from those of the chuck 23.

[0057] For example, as described above, the chuck 23 holds the substrate 102 on the reference side (the substrate 102 on the lower side in the direction of gravity) when separating the bonded substrate 100 into the substrates 101 and 102. Therefore, the dimension of the surface 23b of the chuck 23 in the direction perpendicular to the rotation central axis 1a may be larger than the dimension of the surface of the chuck 21 on the bonded substrate 100 side (the surface that adsorbs the substrate 101). In this way, the posture of the bonded substrate 100 can be stabilized during the separation process.

[0058] Furthermore, the recess 23e for capturing the liquid 40a can be omitted from the chuck 21. That is, the recess 23e may be provided only in the chuck 23. If the recess 23e is not provided in the chuck 21, the liquid 40a sprayed from the separation unit 40 will easily penetrate between the chuck 21 and the bonded substrate 100 (substrate 101), which may weaken the holding force of the chuck 21. However, as long as the holding force (adsorption force) of the chuck 23 that holds the lower surface in the direction of gravity, which serves as the reference for separation processing, is not reduced, even if the holding force of the chuck 21 is weakened, it is possible to prevent the position of the bonded substrate 100 from shifting relative to the rotation center axis 1a.

[0059] That is, the recess 23e can be provided at least in the chuck 23. However, if the recess 23e is provided in the chuck 23 and the chuck 21, for example, even if the liquid 40a penetrates into either the chuck 23 or the chuck 21 and the holding force (adsorption force) of one of the chucks decreases, it is possible to prevent the position of the bonded substrate 100 from shifting relative to the rotation central axis 1a.

[0060] FIG. 4 is a schematic perspective view illustrating the configuration of a chuck 123 according to another embodiment. FIG. 5 is a schematic cross-sectional view of the chuck 123 in FIG. 4 taken along line B-B. As shown in FIGS. 4 and 5, the chuck 123 may be configured by adding a hole 23e1 to the chuck 23 described above. At least one hole 23e1 may be provided. One end of the hole 23e1 is connected to the recess 23e. For example, one end of the hole 23e1 may be connected to the vicinity of the bottom surface of the recess 23e. The other end of the hole 23e1 opens to a side surface of the chuck 123. When multiple holes 23e1 are provided, the multiple holes 23e1 may be arranged side by side along the side surface of the chuck 123. In this case, the multiple holes 23e1 may be provided at positions that are rotationally symmetrical about the central axis 23a.

[0061] If hole 23e1 is provided, centrifugal force makes it easier to discharge liquid 40a trapped in recess 23e to the outside of chuck 123. Therefore, liquid 40a trapped in recess 23e can be further prevented from reaching recess 23d, recess 23d1, and hole 23c, thereby further preventing a decrease in the force (adsorption force) holding bonded substrate 100. As a result, it is possible to further prevent a misalignment of bonded substrate 100 with respect to rotation center axis 1a from hindering uniform separation, reducing separation efficiency, or causing damage to at least one of substrate 101 and substrate 102.

[0062] When the recess 23e is provided in the chuck 21, a hole 23e1 can be provided in the chuck 21.

[0063] The opening size, arrangement, number, etc. of the holes 23e1 can be changed as appropriate depending on the pressure and flow rate of the ejected liquid 40a, the required holding power (adsorption power), etc. For example, these can be determined as appropriate by conducting experiments or simulations.

[0064] 6A and 6B are schematic cross-sectional views illustrating the configuration of chucks 123a and 123b according to other embodiments. As shown in FIG. 6A, the chuck 123a may be configured by adding an inclined surface 23e2 to the chuck 23 described above. The inclined surface 23e2 may be provided over the entire peripheral area of ​​the chuck 123a, or may be provided over a partial area. The inclined surface 23e2 may be a flat surface or a curved surface. The inclined surface 23e2 is inclined in a direction away from the surface 23b as it approaches the peripheral edge of the surface 23b.

[0065] 6(B), the chuck 123b may be configured by adding a step 23e3 to the above-described chuck 23. The step 23e3 may be provided over the entire peripheral area of ​​the chuck 123b, or may be provided over a partial area. The distance between the surface of the surface 23b of the chuck 123b that adsorbs the bonded substrate 100 and the step 23e3 is shorter than the distance between the surface 23b of the chuck 123b and the bottom surface of the recess 23e.

[0066] If the inclined surface 23e2 or the step 23e3 is provided, centrifugal force can easily drain the liquid 40a trapped in the recess 23e to the outside of the chucks 123a and 123b. Therefore, the liquid 40a trapped in the recess 23e can be further prevented from reaching the recess 23d, the recess 23d1, and the hole 23c, thereby further preventing a decrease in the force (adsorption force) holding the bonded substrate 100. As a result, it is possible to further prevent a misalignment of the bonded substrate 100 with respect to the rotation center axis 1a, which would hinder uniform separation and reduce separation efficiency, or to further prevent damage to at least one of the substrates 101 and 102.

[0067] When the recess 23e is provided in the chuck 21, the chuck 21 may be provided with an inclined surface 23e2 or a step 23e3.

[0068] The dimensions, arrangement, and number of the inclined surface 23e2 and the step 23e3 can be changed as appropriate depending on the pressure and flow rate of the ejected liquid 40a, the required holding power (adsorption power), etc. For example, these can be determined as appropriate through experiments and simulations. Also, the holes 23e1, the inclined surface 23e2, and the step 23e3 can be used in combination as appropriate.

[0069] Next, we will explain the operation of the substrate separating apparatus 1, i.e., the method for separating the bonded substrate 100. Figures 7A to 7H are schematic views illustrating the operation of the substrate separating apparatus 1. Figure 8 is a flowchart illustrating the procedure for separating the bonded substrate 100.

[0070] As shown in FIG. 7A, when the substrate separating apparatus 1 is started, the pin 31, the arm 32, and the chuck 23 are at their lowest positions.

[0071] Next, as shown in Fig. 7(B) and step S101 in Fig. 8, the bonded substrate 100 is placed on the arm 32 by the conveying device 200. Next, as shown in Fig. 7(C) and step S102 in Fig. 8, the arm 32 on which the bonded substrate 100 is placed is raised to a predetermined position.

[0072] Next, as shown in Fig. 7(D), the chuck 23 rises and contacts the bonded substrate 100 (substrate 102). At this time, a small gap is formed between the bonded substrate 100 and the arm 32. Next, as shown in Fig. 7(E) and step S103 in Fig. 8, the bonded substrate 100 is positioned. For example, the multiple pins 31 are moved toward the rotation axis 1a, and the multiple pins 31 press against the side surfaces of the bonded substrate 100, thereby aligning the center of the bonded substrate 100 with the position of the rotation axis 1a.

[0073] Next, as shown in Fig. 7(F), the multiple pins 31 are moved in a direction away from the rotation central axis 1a. Next, as shown in Fig. 7(G) and step S104 in Fig. 8, the arm 32 is lowered and the bonded substrate 100 is transferred to the chuck 23. Next, as shown in Fig. 7(H) and step S105 in Fig. 8, the chuck 23 is further raised and the bonded substrate 100 is held between the chucks 21 and 23. At this time, the bonded substrate 100 is vacuum-adsorbed by the chucks 21 and 23.

[0074] Next, as shown in steps S106 to S113 of Fig. 8, a separation step of the bonded substrate 100 is performed. Figs. 9 to 11 are schematic diagrams illustrating the separation of the bonded substrate 100. Note that the shaded areas in Figs. 9 to 11 represent the separated regions.

[0075] In the separation process of the bonded substrate 100, first, the chucks 21 and 23 are rotated to rotate the bonded substrate 100 held by suction on the chucks 21 and 23 (step S106 in FIG. 8).

[0076] Next, the separation initiation step is carried out as shown in Fig. 9 and steps S107 to S109 in Fig. 8. First, as shown in Fig. 9, the nozzle 41 is moved to the vicinity of the periphery of the bonded substrate 100, and the liquid 40a is sprayed from the nozzle 41 to a predetermined position on the side of the bonded substrate 100, between the substrates 101 and 102. At this time, since the bonded substrate 100 is rotating, separation can be carried out over the entire periphery of the bonded substrate 100.

[0077] Next, as shown in Figures 10 and 11, and steps S110 to S113 in Figure 8, separation of the bonded substrate 100 is advanced to separate the bonded substrate 100 into the substrate 101 and the substrate 102. Specifically, first, as shown in Figure 10 and steps S110 to S111 in Figure 8, the nozzle 41 is moved so as to follow the separated region, and separation can be performed in the region between the periphery and the central region of the bonded substrate 100. Then, as shown in Figure 11, liquid 40a is sprayed from the nozzle 41 toward the center of the bonded substrate 100, and separation can be performed in the central region of the substrate 100.

[0078] In the above-described separation process of the bonded substrate 100, the nozzle 41 can be moved in an arc-shaped trajectory from the separation start position to the separation position at the center of the bonded substrate 100, as shown in Fig. 9. Furthermore, the nozzle 41 is moved so that the distance d between the nozzle 41 and the bonded substrate 100 is kept substantially constant. By moving the nozzle 41 so that the distance d is kept substantially constant, the ejection port 41a of the nozzle 41 can be brought as close as possible to the side surface of the bonded substrate 100.

[0079] Furthermore, since the liquid 40a is sprayed while the nozzle 41 is moved along the arc-shaped trajectory, the liquid 40a is sprayed toward a region Ra that is a part of the periphery of the bonded substrate 100. The region Ra is a region that includes an arc with a central angle of 90 degrees on the periphery of the bonded substrate 100. Furthermore, since the bonded substrate 100 is rotating during separation of the region Ra, separation can be performed in the entire region of the bonded substrate 100.

[0080] As described above, the liquid 40a that has entered between the chuck 23 and the substrate 102 is captured by the recess 23e and is discharged by centrifugal force to the outside of the chuck 23. Therefore, it is possible to prevent a decrease in the force (adsorption force) that holds the bonded substrate 100 (substrate 102).

[0081] Furthermore, if the chuck 21 is also provided with the recess 23e, the liquid 40a that has entered between the chuck 21 and the substrate 101 is captured by the recess 23e and is discharged by centrifugal force to the outside of the chuck 21. Therefore, it is possible to prevent a decrease in the force (adsorption force) that holds the bonded substrate 100 (substrate 101).

[0082] Next, as shown in FIG. 11 and steps S112 to S114 of FIG. 8, when separation has progressed to the center of the bonded substrate 100, spraying of the liquid 40a from the nozzle 41 is stopped. After separation of the bonded substrate 100 is complete, the nozzle 41 returns to a standby position away from the bonded substrate 100 (see FIG. 9). Then, rotation of the chucks 21 and 23 is stopped, thereby stopping the rotation of the bonded substrate 100 after separation. Thereafter, the vacuum suction of the chucks 21 and 23 is released, and the steps illustrated in FIGS. 7(B) to 7(H) are performed in reverse order, starting from the step in FIG. 7(H). The separated bonded substrate 100 is then transported out of the substrate separating apparatus 1 by the transport device 200. In this manner, the bonded substrate 100 can be separated.

[0083] The above are examples of the embodiments. However, the present invention is not limited to these descriptions. Those skilled in the art may appropriately add, delete, or modify components of the above-described embodiments, or may add, omit, or modify processes or conditions, as long as the features of the present invention are included within the scope of the present invention. For example, the shape, dimensions, materials, and arrangement of each element of the substrate separating apparatus 1 are not limited to those illustrated and can be modified as appropriate. Furthermore, the elements of the above-described embodiments can be combined to the greatest extent possible, and such combinations are also included within the scope of the present invention as long as they include the features of the present invention.

[0084] REFERENCE SIGNS LIST 1 substrate separation device 1a rotation central axis 20 holding portion 21 chuck 23 chuck 23b surface 23c hole 23d recess 23d1 recess 23e recess 23e1 hole 23e2 inclined surface 23e3 step 24 drive portion 26 exhaust portion 30 positioning portion 40 separation portion 40a liquid 41 nozzle 42 liquid supply portion 50 controller 100 bonded substrate 101 substrate 102 substrate 123 chuck 123a chuck 123b chuck

Claims

1. A substrate separating device comprising: a first chuck for suction-holding one side of a bonded substrate formed by bonding a pair of substrates together; a second chuck for holding the other side of the bonded substrate; an exhaust unit connected to the first chuck; a drive unit for rotating the first chuck and the second chuck; and a nozzle for spraying liquid onto a side of the bonded substrate, wherein the first chuck has a first recess connected to the exhaust unit and a second recess not connected to the exhaust unit, the first recess opening into a first surface of the first chuck facing the bonded substrate, and the second recess opening into a region of the first surface between a region where the first recess opens and a periphery of the first surface.

2. A substrate separating apparatus according to claim 1, wherein said first chuck further has a hole, one end of which is connected to said second recess and the other end of which opens to a side surface of said first chuck.

3. A substrate separating apparatus according to claim 1 or 2, wherein the second recess is frame-shaped and surrounds the area where the first recess is open.

4. A substrate separating apparatus according to claim 1 or 2, wherein the second recess extends along the periphery of the first surface.

5. A substrate separating apparatus according to claim 1 or 2, wherein the distance between the second recess and the periphery of the first surface is shorter than the distance between the second recess and the first recess.

6. A substrate separating device as described in claim 1, wherein the second chuck has a third recess connected to the exhaust section and a fourth recess not connected to the exhaust section, the third recess opening into a second surface of the second chuck facing the bonded substrate, and the fourth recess opening into a region of the second surface between a region where the third recess opens and a periphery of the second surface.

7. A substrate separating apparatus according to claim 6, wherein said second chuck further has a hole, one end of which is connected to said fourth recess and the other end of which opens to a side surface of said second chuck.

8. A substrate separating apparatus according to claim 6 or 7, wherein the fourth recess is frame-shaped and surrounds the area where the third recess is open.

9. A substrate separating apparatus according to claim 6 or 7, wherein the fourth recess extends along the periphery of the second surface.

10. A substrate separating apparatus according to claim 6 or 7, wherein the distance between the fourth recess and the peripheral edge of the second surface is shorter than the distance between the fourth recess and the third recess.

11. A substrate separation device as described in claim 1, wherein the first chuck and the second chuck are arranged to sandwich the bonded substrate above and below in the direction of gravity, and the first chuck holds the surface of the bonded substrate below in the direction of gravity.

12. A substrate separating device as described in claim 1, wherein an inclined surface is provided between the second recess and the peripheral edge of the first surface of the first chuck, the inclined surface inclining in a direction away from the bonded substrate held on the first surface as it approaches the peripheral edge.

13. A substrate separating device as claimed in claim 1, wherein a step is provided on the periphery of the first surface of the first chuck so as to separate it from the bonded substrate held on the first surface, and the second recess opens into the step.

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