Peeling method, peeling device and peeling system

Abstract

[Problem] To provide a technique that can improve the efficiency of the peeling process. [Solution] The peeling method disclosed herein includes: a holding process; and a peeling process. The holding process involves holding an overlapping substrate to which a first substrate and a second substrate are bonded. The peeling process involves peeling the first substrate from the overlapping substrate, starting from a side surface of the overlapping substrate. Furthermore, the peeling process includes a process of contacting a fluid containing water with the side surface.

Description

[Technical Field]

[0001] This disclosure relates to a stripping method, a stripping apparatus, and a stripping system. [Previous Technology]

[0002] In recent years, for example, in the manufacturing process of semiconductor devices, there has been progress in increasing the diameter and thinning of semiconductor substrates such as silicon wafers or compound semiconductor wafers. Large-diameter and thin semiconductor substrates may warp or crack during transport or polishing processes. Therefore, after reinforcing the semiconductor substrate by attaching a support substrate to it, transport or polishing is performed, followed by a process of peeling the support substrate off the semiconductor substrate (see Patent Document 1). [Prior Art Documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2015-35562 [Summary of the Invention]

[0004] [The problem that this invention aims to solve]

[0005] This disclosure provides a technique to improve the efficiency of stripping processes. [Means for solving the problem]

[0006] The peeling method disclosed herein includes: a holding process; and a peeling process. The holding process involves holding the overlapping substrates to which the first substrate and the second substrate are bonded. The peeling process involves peeling the first substrate from the overlapping substrate, starting from a side surface of the first substrate. Furthermore, the peeling process includes contacting the side surface with a fluid containing water. [Effects of the Invention]

[0007] According to this disclosure, the stripping process can be made more efficient.

Implementation Method

[0009] Hereinafter, with reference to the accompanying drawings, embodiments of the peeling method, peeling apparatus, and peeling system disclosed in this application are described in detail. Furthermore, this disclosure is not limited to the embodiments shown below. It should also be noted that the drawings are schematic diagrams, and the dimensional relationships and ratios of the elements may sometimes differ from reality. Moreover, the drawings may sometimes contain portions where the dimensional relationships or ratios differ from each other.

[0010] In recent years, for example, in the manufacturing process of semiconductor devices, there has been progress in increasing the diameter and thinning of semiconductor substrates such as silicon wafers or compound semiconductor wafers. Large-diameter and thin semiconductor substrates may warp or crack during transport or polishing. Therefore, after reinforcing the semiconductor substrate by attaching a support substrate to it, the substrate is transported or polished, and then the support substrate is peeled off from the semiconductor substrate.

[0011] Furthermore, in recent years, apart from composite substrates formed by bonding substrates together with adhesives, most composite substrates are formed by bonding substrates together with van der Waals forces and hydrogen bonds (i.e., intermolecular forces). On the other hand, there is room for further improvement in the technology of "efficiently performing the process of peeling one substrate from such a composite substrate with high bonding strength".

[0012] Therefore, we expect to achieve a technology that can overcome the above-mentioned problems and make the stripping process more efficient.

[0013] <Composition of the peeling system> First, the composition of the peeling system 1 in the embodiment will be described with reference to Figures 1 and 2. Figure 1 is a schematic plan view showing the composition of the peeling system 1 in the embodiment. Figure 2 is a schematic side view of the overlapping substrate T in the embodiment.

[0014] In addition, in the following, the X-axis direction, Y-axis direction and Z-axis direction are defined as mutually orthogonal in order to clarify the positional relationship, and the positive Z-axis direction is set as the vertical upward direction.

[0015] The peeling system 1 shown in FIG1 peels the first substrate W1 from the overlapping substrate T, for example, which is "formed by bonding the first substrate W1 and the second substrate W2 together by intermolecular forces as shown in FIG2". In the following, the first substrate W1 is referred to as "upper wafer W1" and the second substrate W2 is referred to as "lower wafer W2". That is, the upper wafer W1 is an example of the first substrate, and the lower wafer W2 is an example of the second substrate.

[0016] Furthermore, in the following description, as shown in FIG2, the side of the upper wafer W1 that is bonded to the lower wafer W2 is referred to as "bonding surface W1j", and the side of the wafer opposite to the bonding surface W1j is referred to as "non-bonding surface W1n". Also, the side of the lower wafer W2 that is bonded to the upper wafer W1 is referred to as "bonding surface W2j", and the side of the wafer opposite to the bonding surface W2j is referred to as "non-bonding surface W2n".

[0017] The first substrate W1 refers to a substrate on which a plurality of electronic circuits are formed, for example, on a semiconductor substrate such as a silicon wafer or a compound semiconductor wafer. The second substrate W2 refers to, for example, a bare wafer on which no electronic circuits are formed. The first substrate W1 and the second substrate W2 have approximately the same diameter. Furthermore, electronic circuits may also be formed on the second substrate W2.

[0018] As shown in Figure 1, the stripping system 1 has two processing blocks: a first processing block 10 and a second processing block 20. The first processing block 10 and the second processing block 20 are arranged adjacent to each other.

[0019] In the first processing block 10, the loading of the overlapping substrate T, the peeling of the overlapping substrate T, the cleaning and unloading of the wafer W2 after peeling are performed. The first processing block 10 includes: a loading and unloading station 11; a first transport area 12; a standby station 13; a peeling station 14; and a first cleaning station 15.

[0020] The inbound / outbound station 11, the standby station 13, the stripping station 14, and the first washing station 15 are configured to be adjacent to the first transport area 12. Specifically, the inbound / outbound station 11 and the standby station 13 are arranged on the negative Y-axis side of the first transport area 12, and the stripping station 14 and the first washing station 15 are arranged on the positive Y-axis side of the first transport area 12.

[0021] At the loading and unloading station 11, there are a plurality of cassette mounting platforms. Each cassette mounting platform holds a cassette Ct that holds an overlapping substrate T and a cassette C2 that holds the stripped wafer W2.

[0022] In the first transport area 12, a first transport device 121 is provided for transporting the overlapping substrate T or the stripped wafer W2. The first transport device 121 includes: a transport arm that can move horizontally, lift vertically, and rotate about the vertical direction; and a substrate holding part that is mounted on the front end of the transport arm.

[0023] In the first transport area 12, the first transport device 121 is used to transport the overlapping substrate T to the standby station 13 and the stripping station 14, or to transport the stripped wafer W2 to the first cleaning station 15 and the transport in and out station 11.

[0024] In addition, in the standby station 13, a standby process is performed to temporarily put the overlapping substrate T to be processed into standby mode as needed. The standby station 13 is provided with a mounting platform on which the overlapping substrate T is carried by the first conveying device 121.

[0025] In the stripping station 14, a stripping device 5 (see Figure 3) is provided, which is used to perform the stripping process of peeling the wafer W1 off from the overlapping substrate T. The specific structure and operation of the stripping device 5 are described below.

[0026] In the first cleaning station 15, the cleaning process of the stripped lower wafer W2 is performed. The first cleaning station 15 is equipped with a first cleaning device for cleaning the stripped lower wafer W2. As the first cleaning device, a cleaning device described, for example, in Japanese Patent Application Publication No. 2013-033925 can be used.

[0027] Furthermore, in the second processing block 20, the cleaning and removal of the wafer W1 after stripping are performed. The second processing block 20 includes: a receiving station 21; a second cleaning station 22; a second transport area 23; and a removal station 24. The second cleaning station 22 is an example of a cleaning device.

[0028] The receiving station 21, the second washing station 22, and the transfer station 24 are configured to be adjacent to the second transfer area 23. Specifically, the receiving station 21 and the second washing station 22 are arranged on the positive Y-axis side of the second transfer area 23, and the transfer station 24 is arranged on the negative Y-axis side of the second transfer area 23.

[0029] The receiving station 21 is configured to be adjacent to the stripping station 14 of the first processing block 10. In this receiving station 21, the receiving process is performed to receive the stripped wafer W1 from the stripping station 14 and transfer it to the second cleaning station 22.

[0030] At the receiving station 21, a second conveying device 211 is provided. The second conveying device 211 has a non-contact holding part such as a Bernoulli chuck, and the wafer W1 after stripping is conveyed in a non-contact manner by the second conveying device 211.

[0031] In the second cleaning station 22, a second cleaning process is performed to clean the stripped wafer W1. The second cleaning station 22 is equipped with a second cleaning device for cleaning the stripped wafer W1. As the second cleaning device, a cleaning device described, for example, in Japanese Patent Application Publication No. 2013-033925 can be used.

[0032] In the second transport area 23, a third transport device 231 is provided for transporting the stripped wafer W1. The third transport device 231 includes: a transport arm capable of horizontal movement, vertical lifting and lowering, and vertical rotation; and a substrate holding part mounted on the front end of the transport arm. In the second transport area 23, the stripped wafer W1 is transported to the delivery station 24 by means of the third transport device 231.

[0033] At the transfer station 24, a plurality of cassette mounting platforms are provided, and each cassette mounting platform holds a cassette C1 that houses the wafer W1 after it has been stripped.

[0034] Furthermore, the stripping system 1 includes a control device 30. The control device 30 controls the operation of the stripping system 1. This control device 30 is, for example, a computer, and includes a control unit 31 and a memory unit 32. The memory unit 32 stores programs for various processes, such as control bonding processes. The control unit 31 controls the operation of the stripping system 1 by reading and executing the programs stored in the memory unit 32.

[0035] In addition, the program may also be recorded on a computer-readable recording medium, and may also be installed from the memory medium into the memory unit 32 of the control device 30. Examples of computer-readable memory media include hard disks (HD), floppy disks (FD), optical discs (CD), magneto-optical discs (MO), and memory cards.

[0036] In the stripping system 1 configured as described above, firstly, the first conveying device 121 of the first processing block 10 takes out the overlapping substrate T from the box Ct placed in the conveying station 11, and moves the taken-out overlapping substrate T into the standby station 13.

[0037] In the case of overlapping substrates T that need to be processed due to processing time differences between devices, a temporary standby unit provided in the standby station 13 can be used to temporarily put the overlapping substrates T into standby mode, thereby shortening the lost time between a series of processes.

[0038] Next, the overlapping substrate T is taken out from the standby station 13 and moved to the stripping station 14 by the first conveying device 121. Moreover, the stripping device 5 disposed in the stripping station 14 performs a stripping process on the overlapping substrate T. By means of this stripping process, the overlapping substrate T is separated into an upper wafer W1 and a lower wafer W2.

[0039] The stripped wafer W2 is taken out from the stripping station 14 and transported to the first cleaning station 15 by the first conveying device 121. In the first cleaning station 15, the first cleaning device performs a first cleaning process on the stripped wafer W2. By the first cleaning process, the bonding surface W2j of the wafer W2 is cleaned.

[0040] After the first cleaning process, the next wafer W2 is removed from the first cleaning station 15 by the first conveying device 121 and placed in the cassette C2 placed in the inbound / outbound station 11. Subsequently, the cassette C2 is removed from the inbound / outbound station 11 and recycled. In this way, the processing of the next wafer W2 is completed.

[0041] On the other hand, in the second processing block 20, the processing of the stripped wafer W1 is performed in parallel with the processing of the first processing block 10.

[0042] In the second processing block 20, firstly, the second conveying device 211 configured at the receiving station 21 takes out the stripped wafer W1 from the stripping station 14 and moves it into the second cleaning station 22.

[0043] Here, after being stripped, the upper wafer W1 is held in a state where its upper surface, i.e., the non-bonding surface W1n side, is held by the stripping device 5. The second conveying device 211 holds the bonding surface W1j side of the upper wafer W1 from below in a non-contact manner. Subsequently, the second conveying device 211 places the held upper wafer W1 in the second cleaning device of the second cleaning station 22 after reversing it.

[0044] Accordingly, the upper wafer W1 is placed in the second cleaning apparatus with the bonding surface W1j facing upward. Moreover, the second cleaning apparatus performs a second cleaning process to clean the bonding surface W1j of the upper wafer W1. Through this second cleaning process, the bonding surface W1j of the upper wafer W1 is cleaned.

[0045] After the second cleaning process, the upper wafer W1 is removed from the second cleaning station 22 and housed in a cassette C1 placed in the outgoing station 24 by the third conveying device 231 located in the second conveying area 23. Subsequently, the cassette C1 is removed from the outgoing station 24 and recycled. In this way, the processing of the upper wafer W1 is completed.

[0046] Thus, the peeling system 1 of the implementation form is configured to have a front end for the overlapping substrate T and the lower wafer W2 after peeling and a front end for the upper wafer W1 after peeling.

[0047] Here, the front end used for the overlapping substrate T and the lower wafer W2 after peeling refers to the loading and unloading station 11 and the first conveying device 121, and the front end used for the upper wafer W1 after peeling refers to the unloading station 24 and the third conveying device 231.

[0048] Thus, since the processes of transferring the upper wafer W1 to the transfer station 11 and the lower wafer W2 to the transfer station 24 can be performed in parallel, a series of substrate processes can be performed efficiently.

[0049] Furthermore, in the stripping system 1 of the embodiment, the stripping station 14 and the second cleaning station 22 are connected via the receiving station 21. Therefore, since the stripped wafer W1 can be directly transported from the stripping station 14 to the second cleaning station 22 without passing through the first transport area 12 or the second transport area 23, the transport of the stripped wafer W1 can be performed smoothly.

[0050] <Composition of the stripping device> Next, referring to FIG3, the composition of the stripping device 5 installed in the stripping station 14 will be described. FIG3 is a schematic side view showing the composition of the stripping device 5 in the embodiment.

[0051] As shown in Figure 3, the stripping device 5 includes a processing chamber 100. An inlet / outlet (not shown) is provided on the side of the processing chamber 100. The inlet / outlet is located on the side of the first conveying area 12 (see Figure 1) and the receiving / receiving station 21 (see Figure 1), respectively.

[0052] The peeling device 5 includes a first holding part 50, a moving part 60, a second holding part 70, a peeling induction part 80 and a fluid supply part 90, which are disposed inside the processing chamber 100.

[0053] The stripping device 5 holds the upper wafer W1 side of the superimposed substrate T from above by means of the first holding part 50, and holds the lower wafer W2 side of the superimposed substrate T from below by means of the second holding part 70. Moreover, the stripping device 5 moves the upper wafer W1 away from the surface of the lower wafer W2 by means of the moving part 60.

[0054] Thereby, the upper wafer W1 held by the first holding part is continuously peeled off from the lower wafer W2 from one end to the other. Hereinafter, each constituent element will be explained in detail.

[0055] The first holding part 50 includes: an elastic member 51; and a plurality of adsorption parts 52. The elastic member 51 is a thin plate-shaped member, for example, formed of a metal such as sheet metal. The elastic member 51 is positioned above the upper wafer W1 and facing the upper wafer W1.

[0056] A plurality of adsorption portions 52 are disposed in the elastic member 51 on the opposite side of the upper wafer W1. Each adsorption portion 52 includes: a body portion 521, which is fixed to the elastic member 51; and an adsorption disk 522, which is disposed at the lower part of the body portion 521.

[0057] Each adsorption part 52 is connected to an air suction device 524, such as a vacuum pump, via an air suction pipe 523. The first holding part 50 uses the attractive force generated by the air suction device 524 to adsorb the non-bonded surface W1n of the upper wafer W1 (see FIG2) through a plurality of adsorption parts 52. In this way, the upper wafer W1 is adsorbed and held in the first holding part 50.

[0058] Furthermore, it is preferable that the adsorption disk 522 provided in the adsorption section 52 is of a type with less deformation. This is because when "the adsorption disk 522 deforms significantly when the moving section 60 pulls the first holding section 50", the adsorbed portion of the upper wafer W1 will deform significantly along with the deformation, which may damage the upper wafer W1 or the lower wafer W2.

[0059] Specifically, as the adsorption tray 522, it is preferable to use, for example, a flat pad with ribs on the adsorption surface or a space height of 0.5 mm or less.

[0060] Here, the structure of the first holding part 50 will be explained in more detail with reference to FIG4. FIG4 is a schematic plan view of the first holding part 50 in the embodiment.

[0061] As shown in FIG. 4, the plurality of adsorption portions 52 provided in the first holding portion 50 are arranged in a ring on the elastic member 51 and face the outer periphery of the upper wafer W1, respectively adsorbing the outer periphery of the upper wafer W1. Here, although an example of providing 8 adsorption portions 52 on the elastic member 51 is shown, the number of adsorption portions 52 provided on the elastic member 51 is not limited to 8.

[0062] The adsorption part 52 among the plurality of adsorption parts 52 that is disposed closest to the peeling start point (in this case, the negative X-axis direction side) is positioned close to the location where the blade 81 (see FIG. 3) of the peeling inducer 80 (described later) abuts against the side of the overlapping substrate T. In other words, the blade 81 of the peeling inducer 80 abuts against the side of the overlapping substrate T near the adsorption part 52 disposed on the negative X-axis direction side.

[0063] The elastic member 51 comprises: a body portion 511; and an extension portion 512. The body portion 511 is a ring-shaped frame with an outer diameter approximately the same as that of the upper wafer W1 and a hollow central portion. A plurality of adsorption portions 52 are arranged in a ring shape along the shape of the body portion 511 on the underside of the body portion 511, that is, on the opposite side of the upper wafer W1.

[0064] The extension 512 refers to a portion of the outer periphery of the main body 511 located on the side closest to the peeling start point (here, the outer periphery on the negative X-axis direction side) that extends toward the opposite side (negative X-axis direction side) of the peeling travel direction. Furthermore, a support member 61 of the moving part 60 is connected to the front end of the extension 512.

[0065] Referring back to Figure 3, other components of the stripping device 5 will be explained. The moving part 60 includes: a support member 61; a moving mechanism 62; and a load cell 63.

[0066] The support member 61 is a member extending in the vertical direction (Z-axis direction), one end of which is connected to the extension 512 of the elastic member 51 (see Figure 4), and the other end is connected to the moving mechanism 62 via the upper base 103.

[0067] The moving mechanism 62 is fixed to the upper part of the upper base 103, causing the support member 61 connected to the lower part to move in the vertical direction. The load element 63 detects the load applied to the support member 61.

[0068] The moving part 60 uses the moving mechanism 62 to move the support member 61 vertically upward, thereby pulling up the first holding part 50 connected to the support member 61. At this time, the moving part 60 pulls the first holding part 50 while controlling the force applied to the upper wafer W1 based on the detection result of the load element 63.

[0069] Here, as shown in FIG4, the support member 61 that becomes the point of force for pulling up is arranged on the opposite side of the direction of peeling than the adsorption part 52 that becomes the fulcrum for pulling up, that is, the adsorption part 52 closest to the peeling starting point (here, the negative X-axis direction side).

[0070] Therefore, on the side of the overlapping substrate T (which becomes the point of action for pulling up), as shown in FIG3, a clockwise rotational force (torque) is generated. In this way, the moving part 60 can roll up the upper wafer W1 from its outer edge and pull it, and can efficiently peel the upper wafer W1 from the lower wafer W2.

[0071] In addition, the first holding part 50 is supported by the moving part 60, which is supported by the upper base 103. Furthermore, the upper base 103 is supported by the fixing member 101 via the support column 102, which is installed on the top of the processing chamber 100.

[0072] The second holding portion 70 is disposed below the first holding portion 50 and adsorbs and holds the lower wafer W2 side of the overlapping substrate T. The second holding portion 70 includes: a circular plate-shaped body portion 71; and a support member 72 to support the body portion 71.

[0073] The main body 71 is made of a metal component, such as aluminum. An adsorption surface 73 is provided on the top of the main body 71. The adsorption surface 73 is a porous medium, such as a resin component made of PCTFE (polychlorotrifluoroethylene).

[0074] Inside the main body 71, an attraction space 74 is formed that communicates with the outside via an adsorption surface 73. The attraction space 74 is connected to an air suction device 712, such as a vacuum pump, via an air suction pipe 711. The second holding part 70 uses the negative pressure generated by the air suction of the air suction device 712 to adsorb the non-bonded surface W2n (see FIG. 2) of the lower wafer W2 onto the adsorption surface 73, thereby adsorbing and holding the superimposed substrate T.

[0075] The adsorption surface 73 of the main body 71 is formed to have a diameter approximately equal to that of the lower wafer W2. In this way, when the fluid L (see FIG. 6) is supplied to the side of the overlapping substrate T, the situation where the fluid L is attracted from the adsorption surface 73 can be suppressed.

[0076] Furthermore, when a non-adsorption portion such as a trench is formed on the adsorption surface of the lower wafer W2, there is a risk that cracks may form on the lower wafer W2 in that non-adsorption portion. Therefore, the adsorption surface 73 of the body portion 71 is formed as a flat surface without a non-adsorption portion such as a trench. This prevents cracks from forming on the lower wafer W2.

[0077] Moreover, since the adsorption surface 73 is formed by a resin component such as PCTFE, damage to the lower wafer W2 can be further suppressed.

[0078] Furthermore, a groove-shaped discharge pipe 75 is provided on the outer periphery of the main body 71, which is different from the adsorption surface 73. The discharge pipe 75 is connected to the discharge device 752 via the discharge pipe 751. In this way, when the fluid L is supplied to the side of the overlapping substrate T, the overflow of the fluid L from the main body 71 can be suppressed.

[0079] The second holding part 70 is supported by a rotary lifting mechanism 104, which is fixed to the bottom surface of the processing chamber 100. The rotary lifting mechanism 104 is an example of a substrate rotating part, and the second holding part 70 is rotated by rotating the support member 72 about a vertical axis. Furthermore, the rotary lifting mechanism 104 raises and lowers the second holding part 70 by moving the support member 72 in the vertical direction.

[0080] Outside the second holding portion 70, a peeling inducer portion 80 is disposed. The peeling inducer portion 80 is formed on the side of the overlapping substrate T at a location that "becomes the starting point for the upper wafer W1 to be peeled from the lower wafer W2".

[0081] The peeling guide part 80 includes: a blade part 81; a moving mechanism 82; and a lifting mechanism 83. The blade part 81 is, for example, a flat blade, which is supported by the moving mechanism 82 with the blade tip protruding toward the overlapping substrate T.

[0082] The moving mechanism 82 moves the blade 81 along a track extending in the X-axis direction. The lifting mechanism 83 is, for example, fixed to the upper base 103, so that the moving mechanism 82 moves in the vertical direction. In this way, the height position of the blade 81, that is, the contact position with the side of the overlapping substrate T, is adjusted.

[0083] The peeling guide 80 is established by adjusting the height of the blade 81 using the lifting mechanism 83, and then moving the blade 81 horizontally (in this case, the positive X-axis direction) using the moving mechanism 82. Furthermore, the peeling guide 80 brings the blade 81 into contact with the junction of the upper wafer W1 and the lower wafer W2 exposed on the side of the overlapping substrate T. This forms a portion on the overlapping substrate T that serves as the starting point for peeling the upper wafer W1 from the lower wafer W2.

[0084] Furthermore, a fluid supply section 90 is disposed outside the second holding section 70. This fluid supply section 90 supplies a fluid L containing water (H2O) to the side surface of the overlay substrate T. For example, the fluid supply section 90 supplies the fluid L to the area where the blade portion 81 of the peeling inducer 80 abuts on the side surface of the overlay substrate T and its vicinity.

[0085] The fluid supply unit 90 includes: a nozzle 91; and a moving mechanism (not shown). The nozzle 91 dispenses fluid L. The moving mechanism is configured to move the nozzle 91 in both vertical and horizontal directions.

[0086] <Details of the peeling process> Next, referring to Figures 5 to 11, details of the peeling process performed by the peeling device 5 will be explained. Figure 5 is a flowchart showing the peeling process performed by the peeling device 5 in the embodiment. Furthermore, the peeling device 5 executes the processing procedures shown in Figure 5 based on the control unit 31 (see Figure 1) of the control device 30 (see Figure 1).

[0087] First, the control unit 31 moves the overlapping substrate T into the processing chamber 100, as shown in FIG6, and holds the lower wafer W2 side of the overlapping substrate T with the second holding part 70 and holds the upper wafer W1 side of the overlapping substrate T with the first holding part 50 (step S101).

[0088] Next, the control unit 31 controls the fluid supply unit 90 to supply fluid L to the side surface of the overlapping substrate T (step S102). In this way, as shown in FIG6, the control unit 31 makes the fluid L contact the side surface of the overlapping substrate T held in the first holding part 50 and the second holding part 70.

[0089] In addition, in the process of step S102, the control unit 31 makes the fluid L contact the side of the overlapping substrate T located near the adsorption unit 52 which is arranged on the negative X-axis side.

[0090] Next, the control unit 31, as shown in FIG7, controls the peeling inducer 80 to push the blade 81 to the side of the overlapping substrate T in contact with the fluid L, and inserts the blade 81 into the junction of the upper wafer W1 and the lower wafer W2 in the overlapping substrate T (step S103).

[0091] That is, in the process of step S103, the control unit 31 pushes the blade 81 to the side of the overlapping substrate T located near the adsorption part 52 which is arranged on the negative X-axis side.

[0092] Here, Figures 8 and 9 are used to explain the effect of the fluid L when the upper wafer W1 is peeled from the overlay substrate T using the blade 81. Figure 8 is a diagram illustrating the change in the state of the joint during the peeling process of the embodiment.

[0093] As shown in FIG8(a), in the superimposed substrate T of the embodiment, the upper wafer W1 and the lower wafer W2 are bonded by a silicate bond (Si-O-Si). On the other hand, when the cutting edge 81 is inserted, stress is applied to the bonding portion, thereby causing the water (H2O) contained in the fluid L to react with the silicate bond, as shown in FIG8(b).

[0094] Moreover, the siloxane bond reacts with water molecules at the junction of the upper wafer W1 and the lower wafer W2, thereby reducing the bonding strength of the junction as shown in FIG8(c) because the siloxane bond is broken.

[0095] Figure 9 shows the difference in bonding strength between the overlapping substrate T when moisture is supplied and when moisture is not supplied during the peeling process. In addition, Figure 9 also shows the types of films (SiCN, TEOS oxide film, ThOx (thermal oxide film)) on the bonding surfaces W1j and W2j and the types of plasma (O2, N2) used when the bonding surfaces W1j and W2j are pretreated during bonding.

[0096] As can be seen from the results shown in Figure 9, by supplying a fluid L containing water to the overlapping substrate T with joints in various states, the bonding strength during the peeling process is reduced.

[0097] Returning to the explanation of Figure 5. The control unit 31, in parallel with the processing of step S103 above, causes the moving part 60 (see Figure 3) to operate (step S104). Specifically, as shown in Figure 10, the control unit 31 moves a part of the outer periphery of the first holding part 50, specifically the extension 512 of the elastic member 51 (see Figure 4), in a direction away from the second holding part 70.

[0098] Thereby, the adsorption part 52 located near the part where the blade 81 is inserted is pulled upward, and the wafer W1 begins to peel off from the overlapping substrate T, starting from the part where the blade 81 is inserted.

[0099] Moreover, as shown in FIG10, after the upper wafer W1 begins to peel off from the overlay substrate T, the fluid L gradually permeates to the rear side of the junction between the upper wafer W1 and the lower wafer W2 through capillary action. Therefore, since a chemical reaction as shown in FIG8 also occurs on the rear side of the junction, the bonding strength can also be reduced on the rear side of the junction.

[0100] Subsequently, the control unit 31 inserts the cutting edge 81 into the junction of the upper wafer W1 and the lower wafer W2, and actuates the moving part 60 to further pull up the first holding part 50. In this way, peeling is continuously performed from the end of the upper wafer W1 on the negative X-axis direction towards the end on the positive X-axis direction. Finally, as shown in FIG11, the upper wafer W1 is peeled from the overlay substrate T (see FIG10). This completes a series of peeling processes.

[0101] As explained so far, in the embodiment, when "the upper wafer W1 is peeled off from the overlay substrate T using the moving part 60 and the cutting part 81", a fluid L containing water is brought into contact with the side of the overlay substrate T. In this way, since the bonding strength between the upper wafer W1 and the lower wafer W2 can be reduced while the peeling process is being performed, the peeling process efficiency can be improved.

[0102] Furthermore, in this embodiment, fluid L is supplied to the side of the overlapping substrate T from the nozzle 91, and the blade 81 is pressed against the side to which fluid L is supplied. In this way, even for overlapping substrates T with strong bonding due to intermolecular forces, peeling can be performed with good precision and efficiency.

[0103] Furthermore, in the embodiment, the fluid L containing water can be a liquid. This allows the fluid L to gradually permeate to the rear side of the junction between the upper wafer W1 and the lower wafer W2 via capillary action. Therefore, according to the embodiment, the stripping process can be further optimized.

[0104] Furthermore, in an embodiment, the fluid L containing water is heated by the heating section (not shown) of the fluid supply section 90. This allows for the promotion of the chemical reaction shown in FIG8 at the junction of the upper wafer W1 and the lower wafer W2, thereby further reducing the bonding strength between the upper wafer W1 and the lower wafer W2.

[0105] Therefore, depending on the implementation, the stripping process can be further made more efficient.

[0106] In addition, the fluid L in the embodiment can be acidic, neutral, or alkaline. For example, when the upper wafer W1 and the lower wafer W2 are bonded by so-called Cu-Cu direct bonding, the fluid L is controlled to be weakly alkaline (pH=7~8), thereby suppressing the deterioration of Cu at the bonding part due to the fluid L.

[0107] <Various Variations> Next, various variations of the embodiment will be described with reference to Figures 12 to 14. In addition, in the following variations, the same symbols are given to the parts that are the same as in the embodiment, thereby omitting repeated explanations.

[0108] FIG12 is an enlarged side view showing one of the peeling processes of Modified Example 1 of Embodiment 1. As shown in FIG12, in Modified Example 1, fluid L is supplied to the side of the overlapping substrate T from the nozzle 91 while the blade 81 is pressed against it. That is, in Modified Example 1, the process of pressing the blade 81 against the side of the overlapping substrate T and the process of supplying fluid L from the nozzle 91 are performed simultaneously.

[0109] In this way, the bonding strength between the upper wafer W1 and the lower wafer W2 can be reduced while the stripping process is being performed. Therefore, according to Modified Example 1, the efficiency of the stripping process can be improved.

[0110] Furthermore, since in Modification 1, the hydrodynamic fluid L is supplied to the starting point of the peeling, the fluid L can effectively penetrate to the rear side of the junction between the upper wafer W1 and the lower wafer W2. Therefore, according to Modification 1, since the bonding strength between the upper wafer W1 and the lower wafer W2 can be further reduced, the peeling process can be further made more efficient.

[0111] Furthermore, in Modified Example 1, the fluid L containing water is heated by the heating section of the fluid supply section 90, just as in the embodiment. This allows for the promotion of the chemical reaction shown in FIG8 at the junction of the upper wafer W1 and the lower wafer W2, thereby further reducing the bonding strength between the upper wafer W1 and the lower wafer W2.

[0112] Furthermore, in Modification 1, the system fluid L can be either a liquid or water vapor. When the fluid L is water vapor, the chemical reaction shown in FIG8 can be further promoted at the junction of the upper wafer W1 and the lower wafer W2. Therefore, according to Modification 1, the stripping process can be further optimized.

[0113] Figure 13 is a schematic plan view showing one aspect of the peeling process in Modified Example 1 of the embodiment. As shown in Figure 13, in Modified Example 1, the peeling process can also be performed while pressing a plurality of (two in the figure) blades 81 against the overlapping substrate T. This further improves the efficiency of the peeling process.

[0114] Furthermore, in Modification 1, as shown in FIG13, a plurality of nozzles 91 (two in the figure) can be used to supply fluid L to a blade 81. In this way, since fluid L can be adequately supplied to the area to be peeled, the peeling process can be further improved in efficiency.

[0115] In addition, although the example in Figure 13 shows an example of using two blades 81, the number of blades 81 may also be three or more. Also, although the example in Figure 13 shows an example of arranging two nozzles 91 on one blade 81, three or more nozzles 91 may also be arranged on one blade 81.

[0116] FIG14 is a schematic side view showing the configuration of the peeling device 5 in Modified Example 2 of Embodiment 2. As shown in FIG14, in Modified Example 2, a storage tank 92 is provided in the fluid supply section 90, which is different from the Embodiment 2.

[0117] The storage tank 92 is configured to store fluid L and to hold the overlapping substrate T inside. Moreover, in the modified example 2, the control unit 31 (see FIG1) performs a peeling process while immersing the overlapping substrate T in the liquid fluid L stored in the storage tank 92.

[0118] In this way, the bonding strength between the upper wafer W1 and the lower wafer W2 can be reduced while the stripping process is being performed. Therefore, according to Modified Example 2, the efficiency of the stripping process can be improved.

[0119] Furthermore, in Modification 2, the fluid L containing water is heated by the heating section of the fluid supply section 90. This allows for the promotion of the chemical reaction shown in FIG8 at the junction of the upper wafer W1 and the lower wafer W2, thereby further reducing the bonding strength between the upper wafer W1 and the lower wafer W2.

[0120] The peeling apparatus 5 of the embodiment includes: a first holding part 50; a second holding part 70; a fluid supply part 90; and a control part 31. The first holding part 50 holds the first substrate (upper wafer W1) of the overlapping substrate T, which is bonded to the first substrate (upper wafer W1) and the second substrate (lower wafer W2), and moves the first substrate (upper wafer W1) away from the second substrate (lower wafer W2). The second holding part 70 holds the second substrate (lower wafer W2) of the overlapping substrate T. The fluid supply part 90 supplies a fluid L containing water to the side of the overlapping substrate T. The control part 31 controls each part. Furthermore, the control part 31 holds the overlapping substrate T with the first holding part 50 and the second holding part 70. Furthermore, the control unit 31, via the fluid supply unit 90, contacts the side surface with a fluid L containing water, and uses the side surface as a starting point to peel the first substrate (upper wafer W1) from the overlapping substrate T. This improves the efficiency of the peeling process.

[0121] Furthermore, in the stripping apparatus 5 of the embodiment, the fluid supply unit 90 has a plurality of nozzles 91 that discharge a fluid L containing water. This further improves the efficiency of the stripping process.

[0122] Furthermore, in the stripping apparatus 5 of the embodiment, the fluid supply unit 90 includes a storage tank 92 for storing liquid, namely, a fluid L containing water. This improves the efficiency of the stripping process.

[0123] Furthermore, in the stripping apparatus 5 of the embodiment, the fluid supply unit 90 includes a heating unit that heats the fluid L containing water. This further improves the efficiency of the stripping process.

[0124] Furthermore, the peeling device 5 in the embodiment further includes a substrate rotating part (rotation lifting mechanism 104) to rotate the second holding part 70. This further improves the efficiency of the peeling process.

[0125] Furthermore, the peeling system 1 of the embodiment includes: a peeling device 5; and a cleaning device (first cleaning station 15, second cleaning station 22). The peeling device 5 peels the first substrate (upper wafer W1) from the overlapping substrate T on which the first substrate (upper wafer W1) and the second substrate (lower wafer W2) are bonded. The cleaning device (first cleaning station 15, second cleaning station 22) cleans the peeled first substrate (upper wafer W1) and the second substrate (lower wafer W2). Furthermore, the peeling device 5 has the above-described configuration. In this way, the peeling process efficiency can be improved.

[0126] Furthermore, the peeling method of the embodiment includes: a holding process (step S101); and a peeling process. The holding process (step S101) involves holding the overlapping substrate T, which bonds the first substrate (upper wafer W1) and the second substrate (lower wafer W2). The peeling process involves peeling the first substrate (upper wafer W1) from the overlapping substrate T, starting from the side surface of the overlapping substrate T. Furthermore, the peeling process includes a process of contacting the side surface with a fluid L containing water (step S102). This improves the efficiency of the peeling process.

[0127] Furthermore, in the stripping method of the implemented form, the fluid L containing water is water vapor. This allows for further efficiency improvement in the stripping process.

[0128] Furthermore, in the stripping method of the implemented form, the fluid L containing water is a liquid. This allows for further efficiency improvement in the stripping process.

[0129] Furthermore, in the peeling method of the implemented form, the peeling process is performed while discharging a fluid L containing water from a plurality of nozzles 91. In this way, the peeling process can be further optimized.

[0130] Furthermore, in the peeling method of the embodiment, the peeling process includes: a supply process (step S102); and a pressing process (step S103). The supply process (step S102) involves supplying a fluid L containing water from the nozzle 91 to the side. The pressing process (step S103) involves pressing the blade 81 against the side where the fluid L containing water has been supplied. In this way, even for overlapping substrates T with strong bonding due to intermolecular forces, peeling can be performed with good precision and efficiency.

[0131] Furthermore, in the peeling method of the implemented form, the peeling process is performed by immersing the overlapping substrate T in a stored fluid L containing water. This improves the efficiency of the peeling process.

[0132] Furthermore, in the stripping method of the implemented form, the fluid L containing water is heated. This further improves the efficiency of the stripping process.

[0133] Furthermore, in the peeling method of the implemented form, in the overlapping substrate T, the first substrate (upper wafer W1) and the second substrate (lower wafer W2) are bonded by intermolecular forces. In this way, an overlapping substrate T formed by firmly bonding the upper wafer W1 and the lower wafer W2 can be realized.

[0134] Although the above describes embodiments of the present disclosure, the present disclosure is not limited to the above embodiments and various modifications can be made without departing from its intent. For example, although the above embodiments illustrate an example of peeling the upper wafer W1 from an overlapping substrate T "formed by bonding the upper wafer W1 and the lower wafer W2 together with intermolecular forces", the present disclosure is not limited to this example.

[0135] For example, in this disclosure, the lower wafer W2 can also be peeled off from the overlapping substrate T. Also, in this disclosure, the upper wafer W1 or the lower wafer W2 can also be peeled off from the overlapping substrate T which is "formed by bonding the upper wafer W1 and the lower wafer W2 with an adhesive".

[0136] It should be understood that the embodiments disclosed herein are illustrative in all respects and not restrictive. In fact, the above embodiments can be implemented in various forms. Furthermore, the above embodiments can also be omitted, substituted, or modified in various forms without departing from the scope and intent of the appended patent application. [Simplified Explanation of the Diagram]

[0008] [Fig. 1] Fig. 1 is a schematic plan view showing the configuration of the peeling system of the embodiment. [Fig. 2] Fig. 2 is a schematic side view of the overlapping substrate of the embodiment. [Fig. 3] Fig. 3 is a schematic side view showing the configuration of the peeling device of the embodiment. [Fig. 4] Fig. 4 is a schematic plan view of the first holding part of the embodiment. [Fig. 5] Fig. 5 is a flowchart showing the peeling process performed by the peeling device of the embodiment. [Fig. 6] Fig. 6 is an enlarged side view showing one process of the peeling process of the embodiment. [Fig. 7] Fig. 7 is an enlarged side view showing one process of the peeling process of the embodiment. [Fig. 8] Fig. 8 is a diagram illustrating the change in the state of the joint during the peeling process of the embodiment. [Fig. 9] Fig. 9 is a diagram showing the difference in bonding strength when moisture is supplied to the overlapping substrate and when moisture is not supplied during the peeling process. [Fig. 10] Fig. 10 is an enlarged side view showing one process of the peeling process of the embodiment. [Fig. 11] Fig. 11 is an enlarged side view showing one of the peeling processes of the embodiment. [Fig. 12] Fig. 12 is an enlarged side view showing one of the peeling processes of modified example 1 of the embodiment. [Fig. 13] Fig. 13 is a schematic plan view showing one of the peeling processes of modified example 1 of the embodiment. [Fig. 14] Fig. 14 is a schematic side view showing the configuration of the peeling device of modified example 2 of the embodiment.

Claims

1. A peeling method, characterized in that it includes: holding an overlapping substrate to which a first substrate and a second substrate are bonded by siloxane bonding; and peeling the first substrate from the overlapping substrate starting from a side surface of the overlapping substrate, wherein the peeling process includes contacting the side surface with a fluid containing water to cause the siloxane bonding to react with water molecules and break the siloxane bonding.

2. As in the stripping method of request item 1, wherein, The aforementioned fluid containing water is water vapor.

3. As in the stripping method of request item 1, wherein, The aforementioned fluid containing water is a liquid.

4. The stripping method as described in any of requests 1 to 3, wherein, The aforementioned stripping process is carried out while the aforementioned fluid containing water is ejected from multiple nozzles.

5. The stripping method as described in any of requests 1 to 3, wherein, The aforementioned stripping process includes: supplying the aforementioned water-containing fluid to the aforementioned side from the nozzle; and pressing the blade against the aforementioned side to which the aforementioned water-containing fluid has been supplied.

6. As in request item 3, the stripping method, wherein, The aforementioned stripping process is carried out by immersing the aforementioned superimposed substrate in the aforementioned stored fluid containing water.

7. The stripping method as described in any of requests 1 to 3, wherein, The aforementioned fluid containing water is heated.

8. The stripping method as described in any of requests 1 to 3, wherein, In the aforementioned overlapping substrates, the first substrate and the second substrate are bonded together by intermolecular forces.

9. A peeling device, characterized in that it comprises: a first holding portion for holding the first substrate of an overlapping substrate in which a first substrate and a second substrate are bonded by siloxane bonding, and for moving the first substrate away from the second substrate; a second holding portion for holding the second substrate of the overlapping substrate; a fluid supply portion for supplying a fluid containing water to a side surface of the overlapping substrate; and a control portion for controlling each portion, wherein the control portion holds the overlapping substrate with the first holding portion and the second holding portion, and with the fluid supply portion, while contacting the side surface with the fluid containing water to cause the siloxane bonds to react with water molecules and break the siloxane bonds, peeling the first substrate from the overlapping substrate starting from the side surface.

10. The stripping device as claimed in claim 9, wherein, The aforementioned fluid supply unit has a plurality of nozzles that discharge the aforementioned fluid containing water.

11. The stripping device as claimed in claim 9, wherein, The aforementioned fluid supply unit includes: a storage tank for storing the aforementioned fluid containing water.

12. The stripping device as described in any of claims 9 to 11, wherein, The aforementioned fluid supply unit includes a heating unit that heats the aforementioned fluid containing water.

13. The stripping device as described in any of claims 9 to 11, wherein, It also includes: a substrate rotating part, which rotates the aforementioned second holding part.

14. A peeling system, characterized in that it comprises: a peeling device for peeling the first substrate from an overlapping substrate to which a first substrate and a second substrate are bonded together by silicone bonding; and a cleaning device for cleaning the peeled first substrate and the second substrate, wherein the peeling device comprises: a first holding portion for holding the first substrate in the overlapping substrate to which the first substrate and the second substrate are bonded, and for moving the first substrate away from the second substrate; a second holding portion for holding the second substrate in the overlapping substrate; a substrate rotating portion for rotating the second holding portion; a fluid supply portion for supplying a fluid including water to a side surface of the overlapping substrate; and a control portion for controlling each portion. The aforementioned control unit holds the aforementioned superimposed substrate with the aforementioned first holding unit and the aforementioned second holding unit, and with the aforementioned fluid supply unit, while bringing the aforementioned water-containing fluid into contact with the aforementioned side surface, causing the aforementioned silicate bonds to react with water molecules and break the aforementioned silicate bonds, the aforementioned side surface is used as the starting point to peel the aforementioned first substrate from the aforementioned superimposed substrate.

Images