Substrate processing device and substrate processing method

Abstract

According to one aspect of the present invention, a substrate processing apparatus includes a processing unit (40), a measuring unit (60), and a control unit (31). The processing unit (40) holds one of the substrates (T) together with an energy-absorbing layer (E) formed between a pair of substrates, and applies at least one of heat energy and light energy to the energy-absorbing layer (E) to peel off the other substrate. The measuring unit (60) measures the displacement of the other substrate within the processing unit (40). The control unit (31) controls each component. Furthermore, the control unit (31) determines whether the other substrate has been peeled off based on the displacement of the other substrate.

Description

Substrate processing apparatus and substrate processing method This invention relates to a substrate processing apparatus and a substrate processing method. In recent years, for example, in the manufacturing process of semiconductor devices, the diameter and thinning of semiconductor substrates such as silicon wafers or compound semiconductor wafers have been increasingly developing. Large-diameter and thin semiconductor substrates are prone to warping or cracking during handling or polishing. Therefore, after reinforcing the semiconductor substrate with a support substrate, handling or polishing is performed, and then the support substrate is peeled off from the semiconductor substrate (see Patent Document 1). [Prior Art Documents] [Patent Document 1] Japanese Patent Application Publication No. 2014-60381 [The problem the invention aims to solve] This invention provides a technique that "enhances the efficiency of the stripping process." [Means for solving the problem] According to one aspect of the present invention, a substrate processing apparatus includes a processing unit, a measuring unit, and a control unit. The processing unit, for an overlapping substrate formed by forming an energy-absorbing layer between a pair of substrates, holds one of the substrates while applying at least one of heat energy and light energy to the energy-absorbing layer to peel off the other substrate. The measuring unit measures the displacement of the other substrate within the processing unit. The control unit controls each unit. Furthermore, the control unit determines whether the other substrate has been peeled off based on the displacement of the other substrate. [Effects of the Invention] According to the present invention, the stripping process can be made efficient. The following detailed description of embodiments of the substrate processing apparatus and substrate processing method disclosed herein is provided with reference to the accompanying drawings. However, the present invention is not limited to the embodiments disclosed herein. Furthermore, the drawings are schematic diagrams, and the dimensional relationships and ratios of the elements may sometimes differ from the actual situation; readers should take note of this. Additionally, the drawings may sometimes include portions with different dimensional relationships or ratios. In recent years, for example, in the manufacturing process of semiconductor devices, semiconductor substrates such as silicon wafers or compound semiconductor wafers have been increasingly developed in terms of larger diameter and thinner profile. Large-diameter and thinner semiconductor substrates may warp or crack during handling or polishing. Therefore, after reinforcing the semiconductor substrate with a support substrate, the substrate is transported or polished, and then the support substrate is peeled off from the semiconductor substrate. In this peeling process, a chamber is used to shield the area around the overlapping substrate, and the chamber is heated to peel the support substrate off from the overlapping substrate. On the other hand, in the aforementioned prior art, since the cavity shields the area around the overlapping substrate, it is impossible to identify whether the peeling process is complete. Therefore, since a sufficiently long heating time is preset, and the peeling process ends after this heating time, it is difficult to efficiently perform the peeling process using the necessary and sufficient time. Therefore, people are looking forward to the realization of a technology that can overcome the above problems and make the stripping process efficient. <Composition of the Peeling System> First, the composition of the peeling system 1 according to the embodiment will be described with reference to Figures 1 and 2. Figure 1 is a schematic top view showing the composition of the peeling system 1 according to the embodiment. Figure 2 is a schematic cross-sectional view of the overlay substrate T according to the embodiment. Furthermore, in the following explanation, in order to clarify the positional relationship, the X-axis, Y-axis and Z-axis directions that are perpendicular to each other are defined, with the positive Z-axis direction being the vertical upward direction. The peeling system 1 shown in Figure 1, for example, peels off the first substrate W1 from the overlapping substrate T shown in Figure 2, which is "formed by bonding the first substrate W1 and the second substrate W2 together by an adhesive layer J". The first substrate W1 and the second substrate W2 are examples of substrates, and the adhesive layer J is an example of an energy absorption layer. Also, the second substrate W2 is an example of one type of substrate, and the first substrate W1 is an example of another type of substrate. In the following description, 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, upper wafer W1 is an example of the first substrate and lower wafer W2 is an example of the second substrate. Furthermore, in the following description, as shown in Figure 2, on the surface of the upper wafer W1, the surface "joined with the lower wafer W2" is designated as "joined surface W1j", and the surface "opposite to joined surface W1j" is designated as "non-joined surface W1n". Similarly, on the surface of the lower wafer W2, the surface "joined with the upper wafer W1" is designated as "joined surface W2j", and the surface "opposite to joined surface W2j" is designated as "non-joined surface W2n". The first substrate W1 is, for example, a substrate formed by forming multiple electronic circuits on a semiconductor substrate such as a silicon wafer or a compound semiconductor wafer. The second substrate W2 is, for example, a bare wafer without electronic circuits. The first substrate W1 and the second substrate W2 have approximately the same diameter. Alternatively, the second substrate W2 may have electronic circuits formed on it. An adhesive layer J is disposed between the bonding surface W1j of the first substrate W1 and the bonding surface W2j of the second substrate W2. The adhesive layer J has, for example, the property of "bubbling due to heat, resulting in a decrease in adhesion (adhesive force)". 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 configured adjacent to each other. In the first processing block 10, the following processes are performed: feeding in the overlay substrate T, peeling off the overlay substrate T, cleaning, and sending out the peeled wafer W2. This first processing block 10 includes: a feed-in / output station 11, a first transport area 12, a standby station 13, a peeling station 14, and a first cleaning station 15. The infeed / outfeed station 11, the standby station 13, the stripping station 14, and the first cleaning station 15 are arranged adjacent to the first transport area 12. Specifically, the infeed / outfeed station 11 and the standby station 13 are arranged side by side on the negative Y-axis side of the first transport area 12, and the stripping station 14 and the first cleaning station 15 are arranged side by side on the positive Y-axis side of the first transport area 12. The infeed / outfeed station 11 is equipped with a plurality of wafer cassette mounting stages. Each wafer cassette mounting stage holds: wafer cassette Ct, which holds the overlay substrate T; and wafer cassette C2, which holds the stripped wafer W2. The first transport area 12 is equipped with a first transport device 121 for transporting the overlapping substrate T or the wafer W2 after peeling. The first transport device 121 includes a transport arm that can move horizontally, move vertically, and rotate around the vertical center; and a substrate holding part installed at the front end of the transport arm. 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 inlet / outlet station 11. In standby station 13, a standby process is carried out as needed to "temporarily put the overlapping substrate T to be processed on standby". This standby station 13 is equipped with a platform for "the overlapping substrate T transported by the first transport device 121". The stripping station 14 is equipped with a stripping device 5 (see Figure 3), which performs the stripping process of "stripping the wafer W1 from the overlapping substrate T". The stripping device 5 is an example of a substrate processing device. The specific structure and operation of the stripping device 5 will be described later. In the first cleaning station 15, the underlying wafer W2 after stripping is cleaned. The first cleaning station 15 is equipped with a first cleaning device for "cleaning the underlying wafer W2 after stripping". As the first cleaning device, for example, the cleaning device disclosed in Japanese Patent Application Publication No. 2013-033925 can be used. Furthermore, in the second processing block 20, the wafer W1 after stripping is cleaned and then sent out. This second processing block 20 includes: a transfer station 21, a second cleaning station 22, a second transport area 23, and a delivery station 24. The second cleaning station 22 is an example of a cleaning apparatus. Transfer station 21, second cleaning station 22, and delivery station 24 are arranged adjacent to the second transport area 23. Specifically, transfer station 21 and second cleaning station 22 are arranged side by side on the positive Y-axis side of the second transport area 23, and delivery station 24 is arranged side by side on the negative Y-axis side of the second transport area 23. Transfer station 21 is configured adjacent to stripping station 14 of first processing block 10. In this transfer station 21, the stripped wafer W1 is received from stripping station 14 and the stripped wafer W1 is delivered to the second cleaning station 22. The transfer station 21 is equipped with a second transport device 211. The second transport device 211 has, for example, a non-contact holding part such as a Bennouri chuck, and the wafer W1 after stripping is transported in a non-contact manner using this second transport device 211. In the second cleaning station 22, a second cleaning process of "cleaning the wafer W1 after stripping" is performed. This second cleaning station 22 is equipped with a second cleaning device for "cleaning the wafer W1 after stripping". As the second cleaning device, for example, the cleaning device disclosed in Japanese Patent Application Publication No. 2013-033925 can be used. The second transport area 23 is equipped with a third transport device 231 for transporting the stripped wafer W1. The third transport device 231 includes a transport arm that can move horizontally, move vertically, and rotate around a vertical center; and a substrate holding part installed at the front end of the transport arm. In the second transport area 23, the stripped wafer W1 is transported to the delivery station 24 using this third transport device 231. The delivery station 24 is equipped with multiple wafer cassette mounting stages. Each wafer cassette mounting stage holds a wafer cassette C1 that "contains the stripped wafer W1". 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, including a control unit 31 and a storage unit 32. The storage unit 32 stores programs for controlling various processes such as bonding processes. The control unit 31 executes the programs stored in the storage unit 32 to control the operation of the stripping system 1. Furthermore, this program can be a program stored on a computer-readable storage medium, or a program installed from that storage medium into the storage unit 32 of the control device 30. Computer-readable storage media include, for example, hard disks (HD), floppy disks (FD), optical discs (CD), magneto-optical discs (MO), and memory cards. In the stripping system 1 configured as described above, firstly, the first transport device 121 of the first processing block 10 takes out the overlapping substrate T from the wafer cassette Ct placed in the infeed station 11 and sends the taken-out overlapping substrate T into the standby station 13. For example, when there is a situation where there is an overlapping substrate T waiting to be processed due to differences in processing time between devices, a temporary standby unit provided in standby station 13 can be used to temporarily put the overlapping substrate T on standby, thereby shortening the time lost between a series of steps. Next, the overlapping substrate T is taken out from the standby station 13 by the first transport device 121 and sent to the stripping station 14. Then, the stripping device 5 provided in the stripping station 14 performs a stripping process on the overlapping substrate T. Through this stripping process, the overlapping substrate T is separated into an upper wafer W1 and a lower wafer W2. After being stripped, the lower wafer W2 is removed from the stripping station 14 by the first transport device 121 and sent to the first cleaning station 15. In the first cleaning station 15, the first cleaning device performs a first cleaning process on the stripped lower wafer W2. Through this first cleaning process, the bonding surface W2j of the lower wafer W2 is cleaned. After the first cleaning process, the lower wafer W2 is removed from the first cleaning station 15 by the first transport device 121 and placed in the wafer cassette C2 placed in the feed-in / feed-out station 11. Then, the wafer cassette C2 is removed from the feed-in / feed-out station 11 and recycled. In this way, the processing of the lower wafer W2 is completed. On the other hand, in parallel with the processing performed in the first processing block 10, the stripped wafer W1 is processed in the second processing block 20. In the second processing block 20, firstly, the second transport device 211, which is configured in the transfer station 21, takes out the stripped wafer W1 from the stripping station 14 and sends it into the second cleaning station 22. Here, after being stripped, the upper wafer W1 is in a state where "the top surface side, i.e., the non-bonding surface W1n side, is held by the stripping device 5". The second transport device 211 holds the bonding surface W1j side of the upper wafer W1 from below in a non-contact manner. Then, the second transport device 211 flips the upper wafer W1 held therein and places it on the second cleaning device of the second cleaning station 22. Therefore, the upper wafer W1 is placed in the second cleaning apparatus with the bonding surface W1j facing upwards. Then, 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. After the second cleaning process, the wafer W1 is removed from the second cleaning station 22 by the third transport device 231 configured in the second transport area 23 and placed in the wafer cassette C1 placed in the delivery station 24. Then, the wafer cassette C1 is removed from the delivery station 24 and recycled. In this way, the processing of the wafer W1 is also completed. As described above, the peeling system 1 according to the embodiment includes: 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. Here, the term "front end for the overlapping substrate T and the lower wafer W2 after peeling" refers to the feed-in / feed-out station 11 and the first transport device 121, and the term "front end for the upper wafer W1 after peeling" refers to the feed-out station 24 and the third transport device 231. In this way, since the processes of "moving the lower wafer W2 to the infeed / outfeed station 11" and "moving the upper wafer W1 to the outfeed station 24" can be performed simultaneously, a series of substrate processing can be carried out efficiently. Furthermore, in the stripping system 1 according to the embodiment, the stripping station 14 and the second cleaning station 22 are connected by the transfer station 21. In this way, since the stripped wafer W1 can be directly sent from the stripping station 14 to the second cleaning station 22 without passing through the first transfer area 12 or the second transfer area 23, the stripped wafer W1 can be transported smoothly. <Composition of the Stripping Device> Next, the composition of the stripping device 5 provided in the stripping station 14 will be described with reference to FIG3. FIG3 is a schematic diagram showing the composition of the stripping device 5 according to an embodiment. As shown in Figure 3, the stripping device 5 includes a processing chamber 100. The processing chamber 100 has inlet and outlet ports (not shown) on its side. These inlet and outlet ports are, for example, located on the side of the first transport area 12 (see Figure 1) and the side of the transfer station 21 (see Figure 1), respectively. The peeling device 5 includes a processing unit 40 and a measuring unit 60, which are disposed inside the processing chamber 100. Furthermore, the processing unit 40 in the embodiment includes a heating chamber 41. The heating chamber 41 has a holding portion 42 and a cover portion 43, which makes the space formed between the holding portion 42 and the cover portion 43 a sealed structure. The holding portion 42 holds the wafer W2 under the overlapping substrate T. The holding portion 42 is formed into a circular plate shape, for example, by a metal component such as aluminum, and is supported by a support member 44 provided below. An adsorption surface 45 is provided on the top surface of the holding part 42. The adsorption surface 45 is formed of a porous material, such as a resin component of PCTFE (polyvinyl chloride). Inside the holding portion 42, a suction space (not shown) is formed that is "connected to the outside via the adsorption surface 45". This suction space is connected to a suction device 45b, such as a vacuum pump, via a suction pipe 45a. The holding portion 42 uses the negative pressure "generated by suction from the suction device 45b" to adsorb the non-bonded surface W2n of the lower wafer W2 (see Figure 2) onto the adsorption surface 45, thereby adsorbing and holding the superimposed substrate T. The cover 43 is, for example, a generally cylindrical shape with an opening at the bottom. The cover 43 is supported by a drive mechanism 46 mounted on the ceiling of the processing chamber 100 by a support member 47. The drive mechanism 46 raises and lowers the cover 43 by moving the support member 47 in a vertical direction. In addition, the control unit 31 (see Figure 1) uses the drive mechanism 46 to lower the cover 43, so that the opening of the cover 43 and the periphery of the retaining part 42 come into contact with each other, making the heating chamber 41 a sealed structure. Furthermore, the control unit 31 can lift the cover 43 so that the cover 43 can be detached from the holding part 42, so that the overlapping substrate T can be stored inside the heating chamber 41, and the upper wafer W1 and lower wafer W2 after the peeling process can be taken out from inside the heating chamber 41. Furthermore, the heating chamber 41 is equipped with a heater 48. The heater 48 is, for example, located inside the retaining portion 42. The control unit 31, by activating the heater 48, can raise the temperature inside the heating chamber 41 to the desired level. Furthermore, in the example shown in Figure 3, the heater 48 is located on the retaining portion 42. However, the present invention is not limited to this example. For instance, the heater 48 may also be located on the cover portion 43, or on both the retaining portion 42 and the cover portion 43. In addition, in the present invention, a heating source may be provided outside the heating chamber 41, and the interior of the heating chamber 41 may be heated using the heat energy supplied from this heating source. The measuring unit 60 of the stripping device 5 measures the displacement of the upper wafer W1 in the processing unit 40. According to the embodiment, the measuring unit 60 includes a laser displacement meter 61 and a ranging unit 62. The laser displacement meter 61 is, for example, disposed above the cover 43 inside the processing chamber 100. That is, the laser displacement meter 61 is disposed outside the heating chamber 41. The laser displacement meter 61 illuminates the laser light L1 onto the wafer W1 side of the "overlapping substrate T held by the holding part 42" via the transparent window member 43a provided on the cover part 43, and receives the light "reflected back by the upper wafer W1 by the laser light L1". The ranging unit 62 is connected to the laser displacement meter 61. Based on the laser light L1 emitted from the laser displacement meter 61 and the reflected light received by the laser displacement meter 61 from the upper wafer W1, it measures the distance D from the laser displacement meter 61 to the upper wafer W1. <Operation of the Stripping Device> Next, the specific operation of the stripping device 5 according to the embodiment will be described with reference to Figures 4 and 5. Figure 4 is a flowchart showing the processing sequence of the stripping process performed by the stripping device 5 according to the embodiment. First, the control unit 31 sends the overlapping substrate T into the heating chamber 41 of the processing chamber 100 (step S101). Then, the control unit 31 activates the suction device 45b, and the holding part 42 holds the wafer W2 under the overlapping substrate T (step S102). Next, the control unit 31 lowers the cover 43, thereby sealing the heating chamber 41 (step S103). In this way, the interior of the heating chamber 41 can be heated efficiently, thus enabling efficient peeling of the overlapping substrate T. Furthermore, in this invention, the processing of step S103 can be performed before the processing of step S102, or it can be performed simultaneously with the processing of step S102. Next, the control unit 31 activates the heater 48 to raise the temperature inside the heating chamber 41 to a predetermined temperature, thereby applying heat energy to the adhesive layer J of the overlay substrate T (step S104). For example, the control unit 31 heats the inside of the heating chamber 41 to about 450 (°C). As a result, the state of the adhesive layer J changes due to heat (e.g., bubbling), and the adhesive force decreases, so the upper wafer W1 begins to peel off from the overlay substrate T. Furthermore, while performing this step S104, the control unit 31 activates the measurement unit 60 to measure the displacement of the upper wafer W1 (step S105). For example, in the implementation sample, the control unit 31 measures the distance D "from the laser displacement meter 61 to the upper wafer W1" as the displacement of the upper wafer W1. Then, as shown in Figure 5, the control unit 31 detects the time-lapse change of the displacement (distance D) of the upper wafer W1 in real time. Figure 5 is a diagram showing an example of the distance D moving "from the laser displacement meter 61 to the upper wafer W1". Next, the control unit 31 determines whether the displacement (distance D) of the upper wafer W1 changes abruptly (step S106). For example, in the implementation sample, the control unit 31 often measures the difference between the moving average of the displacement (distance D) of the first wafer W1 at each time point in the stripping process and the moving average of the displacement (distance D) of the first wafer W1 immediately preceding each time point. Furthermore, if the difference between the moving average value of the displacement (distance D) of the first wafer W1 at a certain point in time and the moving average value of the displacement (distance D) of the first wafer W1 immediately preceding that point in time is greater than a specified value, the control unit 31 determines that the second wafer W2 is peeled off from the overlay substrate T at that point in time. This specified value is, for example, around tens of micrometers. That is, when the displacement (distance D) of the upper wafer W1 changes rapidly (step S106 is Yes), the control unit 31 determines that the second wafer W2 is peeled off from the overlapping substrate T and ends the peeling process (step S107). Then, the control unit 31 sends the upper wafer W1 and the lower wafer W2 out of the processing chamber 100 (step S108) to complete the processing. On the other hand, if the displacement (distance D) of the upper wafer W1 does not change rapidly (step S106 is No), the process returns to the processing steps S104 and S105. For example, in the example of Figure 5, due to the bubbling and expansion of the adhesive layer J, the thickness of the overlapping substrate T increases sharply, and the first wafer W1 is completely peeled off. Therefore, when the peeling is completed, the distance D "from the laser displacement meter 61 to the upper wafer W1" is shortened sharply. As described above, in the implementation sample, in the overlapping substrate T where the second wafer W2 is held on one side and the peeling process is performed on the other side, the peeling process is determined to be complete based on the displacement (distance D) of the first wafer W1 that is not held. Therefore, since the removal of the upper wafer W1 can be detected with high accuracy, the removal process can be ended at this detection point (in this case, the heat treatment in the heating chamber 41). Therefore, by implementing this method, the stripping process can be made more efficient because it can suppress the situation where "extra time is used during the stripping process". Furthermore, in the implementation sample, when the displacement (distance D) of the upper wafer W1 changes rapidly, it can be determined that the upper wafer W1 has been stripped. In this way, since the stripping of the upper wafer W1 can be detected immediately, the stripping process can be made more efficient. Furthermore, in the above embodiment, the difference between the moving average of the displacement of the first wafer W1 at each time point during the stripping process and the moving average of the displacement of the first wafer W1 immediately preceding each time point is used to determine whether the displacement of the upper wafer W1 changes abruptly. However, the present invention is not limited to this example, and various known methods can also be used to determine whether the displacement of the upper wafer W1 changes abruptly. Furthermore, in the above embodiment, the distance D from the laser displacement meter 61 to the upper wafer W1 is used as the displacement of the upper wafer W1. However, the present invention is not limited to this example. For example, the displacement of the upper wafer W1 can also be used as the relative position of the upper wafer W1 with respect to another reference point. Furthermore, in the embodiment, the measuring unit 60 can measure the displacement of the upper wafer W1 without contacting it. This helps to suppress damage to the upper wafer W1. Furthermore, in the above embodiment, the measuring unit 60 uses a laser displacement meter 61 to measure the displacement of the upper wafer W1, but the present invention is not limited to this example. For example, the measurement unit 60 can measure the displacement of the upper wafer W1 using an ultrasonic displacement meter or a camera. Furthermore, when measuring the displacement of the upper wafer W1 using a camera, this camera can be positioned to the side of the overlapping substrate T. Furthermore, in the embodiment, the measuring unit 60 can measure the displacement of the upper wafer W1 via the window member 43a of the cover portion 43. In this way, since the displacement of the upper wafer W1 can be measured while the surrounding area of ​​the overlay substrate T is enclosed, the peeling process time of the overlay substrate T can be further shortened. Therefore, by implementing this method, the stripping process can be made more efficient. <Modification 1> Next, various modifications of the embodiment will be described with reference to Figures 6 to 11. Figure 6 is a schematic cross-sectional view of the overlay substrate T according to Modification 1 of the embodiment. As shown in Figure 6, in the overlay substrate T of Modification 1, an etch layer A is disposed between the adhesive layer J and the first wafer W1, which is different from the embodiment described above. This etching layer A is another example of an energy absorption layer. It absorbs the laser light L2 (see Figure 7) "irradiated from the laser irradiation unit 51 (see Figure 7) described later" and has the properties of melting and evaporation. The etching layer A is, for example, composed of an LTHC (Light to Heat Conversion) film or an Al (aluminum) film. Figure 7 is a schematic diagram showing the configuration of the peeling device 5 according to the modified example 1 of the embodiment. As shown in Figure 7, the peeling device 5 of the modified example 1, like the one in the above embodiment, includes a processing unit 40 and a measuring unit 60. Furthermore, the processing unit 40 according to Modified Example 1 has a holding part 42 that can be rotated by the drive mechanism 49 and a laser irradiation part 51. The holding part 42 uses the negative pressure generated by the suction device 45b to adsorb the non-bonded surface W2n of the lower wafer W2 (see Figure 6) onto the adsorption surface 45, thereby adsorbing and holding the superimposed substrate T. The laser irradiation unit 51 can move horizontally above the holding unit 42 and irradiate laser light L2 downwards. This laser light L2 has, for example, a flat-top distribution with a "more uniform energy distribution than a Gaussian distribution". In addition, the control unit 31 controls the laser irradiation unit 51 to scan and irradiate the etch layer A (see Figure 6) of the superimposed substrate T held by the holding unit 42 while scanning, so as to scrape off all the etch layer A and peel off the first wafer W1 from the superimposed substrate T. That is, in this modified example 1, the first wafer W1 is peeled off from the overlapping substrate T by applying light energy to the etch layer A. Furthermore, in the modified example 1, the laser displacement meter 61 is configured in the same environment as the laser irradiation unit 51, irradiating the wafer W1 side of the overlapping substrate T held by the holding unit 42 with laser light L1, and receiving the light reflected back by the upper wafer W1. In this way, the measurement unit 60 measures the distance D from the laser displacement meter 61 to the upper wafer W1. Figure 8 is a flowchart showing the processing sequence of the peeling process performed by the peeling device 5 according to the modified example 1 of the embodiment. First, the control unit 31 sends the overlapping substrate T into the processing chamber 100 (step S201). Then, the control unit 31 activates the suction device 45b, and the holding part 42 holds the wafer W2 under the overlapping substrate T (step S202). Next, the control unit 31 activates the laser irradiation unit 51 to apply light energy to the etch layer A of the overlapping substrate T (step S203). Simultaneously with this step S203, the control unit 31 activates the measurement unit 60 to measure the displacement of the upper wafer W1 (step S204). For example, in Modified Example 1, the control unit 31 measures the distance D "from the laser displacement meter 61 to the upper wafer W1" as the displacement of the upper wafer W1. Next, the control unit 31 determines whether the displacement (distance D) of the upper wafer W1 changes abruptly (step S205). If the displacement (distance D) of the upper wafer W1 changes abruptly (step S205 is Yes), the control unit 31 determines that the second wafer W2 has been peeled off from the overlapping substrate T and ends the peeling process (step S206). Then, the control unit 31 sends the upper wafer W1 and the lower wafer W2 out of the processing chamber 100 (step S207) to complete the processing. On the other hand, if the displacement (distance D) of the upper wafer W1 does not change rapidly (step S205 is No), the process returns to the processing steps S203 and S204. In this variation 1, for example, due to the grinding of the etch layer A, the thickness of the overlapping substrate T is rapidly reduced, and the first wafer W1 is completely peeled off. Therefore, when the peeling is completed, the distance D "from the laser displacement meter 61 to the upper wafer W1" increases rapidly. As described above, in Modified Example 1, similarly to the above embodiment, in the overlapping substrate T that holds the second wafer W2 while performing a peeling process, the displacement (distance D) of the first wafer W1 that is not held is used to determine whether the peeling process is complete. Therefore, since the removal of the upper wafer W1 can be detected with high accuracy, the removal process can be ended at this detection point (in this case, the laser irradiation process of the laser irradiation unit 51). Therefore, according to variation 1, since the situation of "using extra time during the stripping process" can be suppressed, the stripping process can be made efficient. Furthermore, in the modified example 1 described so far, laser light L2 is irradiated onto the etch layer A "displaced between the first wafer W1 and the second wafer W2" to peel off the first wafer W1, but the present invention is not limited to this example. For example, silicon oxide films are formed on the bonding surfaces W1j of the first wafer W1 and W2j of the second wafer W2, respectively. In the overlapping substrate T where these silicon oxide films are directly bonded to each other, laser light L2 is irradiated onto the silicon oxide films, which serve as energy absorption layers, and a peeling process is performed. Similarly, since the thickness of the overlapping substrate T changes drastically when the peeling process is completed, the upper wafer W1 can be accurately detected as peeled off by measuring the displacement of the first wafer W1 using the measuring unit 60. Furthermore, in this invention, the adhesive layer J of the overlapping substrate T shown in FIG2 is irradiated with laser light L2 to change the state of the adhesive layer J (e.g., blistering), thereby peeling the wafer W1 off the overlapping substrate T. Similarly, since the thickness of the overlapping substrate T changes drastically when the peeling process is completed, the upper wafer W1 can be accurately detected as peeled off by measuring the displacement of the first wafer W1 using the measuring unit 60. <Modification Example 2> Figure 9 is a diagram illustrating the peeling process according to Embodiment Example 2. As shown in Figure 9(a), in Modification Example 2, an adhesive layer J and an energy absorption layer E are disposed between the first wafer W1 and the second wafer W2 constituting the overlapping substrate T. In variation 2, for example, the adhesive layer J is configured close to the bonding surface W2j of the second wafer W2, and the energy absorption layer E is configured close to the bonding surface W1j of the first wafer W1. This energy absorption layer E is a layer that absorbs at least one of thermal energy and light energy, for example, it absorbs laser light L2 (see Figure 7) and generates heat. Furthermore, in Modified Example 2, the control unit 31 (see Figure 1) irradiates the energy absorption layer E of the overlapping substrate T with laser light L2. As a result, the energy absorption layer E heats up, and the state of the adhesive layer J changes (e.g., bubbling). Therefore, as shown in Figure 9(b), the upper wafer W1 is peeled off from the overlapping substrate T. In this modified example 2, an energy-absorbing layer E remains on the bonding surface W1j of the first wafer W1, while on the other hand, a large portion of the adhesive layer J disappears from the bonding surface W2j of the second wafer W2. That is, in modified example 2, the layer that absorbs at least one of thermal energy and light energy (in this case, the energy-absorbing layer E) and the layer that disappears due to the peeling process are different. Similarly, since the thickness of the overlapping substrate T changes drastically when the peeling process is completed, the upper wafer W1 can be accurately detected as peeled off by measuring the displacement of the first wafer W1 using the measuring unit 60 (see Figure 7). Furthermore, in this modified example 2, the adhesive layer J is changed by causing the energy-absorbing layer E to absorb light energy, but it is not limited to this. The adhesive layer J can also be changed by causing the energy-absorbing layer E to absorb heat energy. <Modification Example 3> Figure 10 is a diagram illustrating the peeling process according to Embodiment Example 3. As shown in Figure 10(a), in Modification Example 3, similar to Modification Example 2 above, an adhesive layer J and an energy absorption layer E are disposed between the first wafer W1 and the second wafer W2 constituting the overlapping substrate T. Furthermore, in Modified Example 3, the control unit 31 (see Figure 1) irradiates the energy absorption layer E of the overlapping substrate T with laser light L2. As a result, the energy absorption layer E heats up, and the adhesive force between the adhesive layer J and the energy absorption layer E decreases. Therefore, as shown in Figure 10(b), the upper wafer W1 is peeled off from the overlapping substrate T. In this modified example 3, an energy absorption layer E remains on the bonding surface W1j of the first wafer W1, and an adhesive layer J remains on the bonding surface W2j of the second wafer W2. Similarly, since the thickness of the overlapping substrate T changes drastically when the peeling process is completed, the upper wafer W1 can be accurately detected as peeled off by measuring the displacement of the first wafer W1 using the measuring unit 60 (see Figure 7). Furthermore, in this modified example 3, the adhesive force between the adhesive layer J and the energy-absorbing layer E is reduced by causing the energy-absorbing layer E to absorb light energy, but this is not the only possibility. For example, in modified example 3, the adhesive force between the adhesive layer J and the energy-absorbing layer E can also be reduced by causing the energy-absorbing layer E to absorb heat energy. <Modification 4> Figure 11 is a diagram illustrating the peeling process according to Embodiment 4. As shown in Figure 11(a), in Modification 4, a first element layer D1 is formed on the bonding surface W1j of the first wafer W1, separated by the energy absorption layer E. A second element layer D2 is formed on the bonding surface W2j of the second wafer W2. Furthermore, in variation 4, as shown in FIG11(b), an overlapping substrate T is formed by bonding the first element layer D1 and the second element layer D2 using known techniques. Furthermore, in Modification 4, the control unit 31 (see Figure 1) irradiates the energy absorption layer E of the overlapping substrate T with laser light L2. As a result, the adhesion between the first wafer W1 and the energy absorption layer E decreases due to the increased temperature of the energy absorption layer E, and thus, as shown in Figure 11(c), the upper wafer W1 is peeled off from the overlapping substrate T. In this case, in modified example 4, the second element layer D2, the first element layer D1, and the energy absorption layer E remain on the bonding surface W2j of the second wafer W2. Similarly, since the thickness of the overlapping substrate T changes drastically when the peeling process is completed, the upper wafer W1 can be accurately detected as peeled off by measuring the displacement of the first wafer W1 using the measuring unit 60 (see Figure 7). Furthermore, in this variation 4, the adhesion between the first wafer W1 and the energy absorption layer E is reduced by absorbing light energy, but this is not the only variation. For example, in variation 4, the adhesion between the first wafer W1 and the energy absorption layer E can also be reduced by absorbing heat energy. The substrate processing apparatus (peeling apparatus 5) according to the embodiment includes a processing unit 40, a measuring unit 60, and a control unit 31. The processing unit 40 holds one of the overlapping substrates T (second wafer W2) and applies at least one of heat energy and light energy to the energy absorption layer E (adhesive layer J, etch layer A) to peel off the other substrate (first wafer W1). The overlapping substrate T has an energy absorption layer E (adhesive layer J, etch layer A) formed between the pair of substrates (first wafer W1, second wafer W2). The measuring unit 60 measures the displacement of the other substrate (first wafer W1) within the processing unit 40. The control unit 31 controls each unit. Furthermore, the control unit 31 determines whether the other substrate (first wafer W1) has been peeled off based on the displacement of the other substrate (first wafer W1). This makes the peeling process more efficient. Furthermore, in the substrate processing apparatus (peeling apparatus 5) according to the embodiment, when the displacement of the other substrate (first wafer W1) changes rapidly, the control unit 31 determines that the other substrate (first wafer W1) has been peeled off. In this way, the peeling process can be made more efficient. Furthermore, in the substrate processing apparatus (stripping apparatus 5) according to the embodiment, the measuring unit 60 measures the displacement of the substrate (first wafer W1) without contacting it. In this way, damage to the upper wafer W1 can be suppressed. Furthermore, in the substrate processing apparatus (stripping apparatus 5) according to the embodiment, the measuring unit 60 includes at least one of a laser displacement meter 61, an ultrasonic displacement meter, and a camera. This can suppress damage to the upper wafer W1. Furthermore, in the substrate processing apparatus (peeling apparatus 5) according to the embodiment, the processing unit 40 includes a heating chamber 41, which is a sealed structure, to apply heat energy to the energy absorption layer E (adhesive layer J, etch layer A). Additionally, the measuring unit 60 measures the displacement of the other substrate (first wafer W1) from outside the heating chamber 41. This makes the peeling process more efficient. Furthermore, in the substrate processing apparatus (peeling apparatus 5) according to the embodiment, the processing unit 40 includes a laser irradiation unit 51 that applies light energy to the energy absorption layer E (adhesive layer J, etch layer A). The measuring unit 60 is also positioned in the same environment as the laser irradiation unit 51. This allows for efficient peeling processing. Furthermore, the substrate processing method according to the embodiment includes: an application step (steps S104, S203), a measurement step (steps S105, S204), and a judgment step (steps S106, S205). In the application step, one substrate (second wafer W2) of the overlapping substrates T is held in place, and at least one of heat energy and light energy is applied to the energy absorption layer E (adhesive layer J, etch layer A). In the overlapping substrates T, the energy absorption layer E (adhesive layer J, etch layer A) is formed between a pair of substrates (first wafer W1, second wafer W2). In the measurement step (steps S105, S204), during the application step (steps S104, S203), the displacement of the other substrate (first wafer W1) is measured. In the judgment step (steps S106, S205), based on the displacement of the other substrate (first wafer W1), it is determined whether the other substrate (first wafer W1) has been peeled off. This makes the stripping process more efficient. The above description pertains to embodiments of the present invention, but the present invention is not limited to the above embodiments. Various modifications can be made without departing from its spirit. For example, in the above embodiments, the upper wafer W1 is peeled off from the overlapping substrate T, but the present invention is not limited to this example. For example, the lower wafer W2 can also be peeled off from the overlapping substrate T. The embodiments disclosed herein should be considered illustrative in all aspects, not limiting. In fact, the above embodiments can be implemented in various ways. Furthermore, the above embodiments can be omitted, substituted, or modified in various ways without departing from the scope and spirit of the patent application in the appendix. 1: Peeling system; 5: Peeling device (an example of a substrate processing device); 10: First processing block; 11: Feeding / outgoing station; 12: First transport area; 121: First transport device; 13: Standby station; 14: Peeling station; 15: First cleaning station; 20: Second processing block; 21: Transfer station; 211: Second transport device; 22: Second cleaning station; 23: Second transport area; 231: Third transport device; 24: Outgoing station; 30: Control device; 31: Control unit; 32: Storage unit; 40: Processing unit; 41: Heating chamber; 42: Holding part; 43: Cover part; 43a: Window component; 44: Support component; 45: Adsorption surface; 45a: Suction pipe; 45b: Suction device; 46: Drive mechanism; 47: Support component; 48: Heater; 49: Drive mechanism; 51: Laser irradiation unit; 60: Measurement unit; 61: Laser displacement meter; 62: Distance measuring unit; 100: Processing chamber A: Etching layer (an example of an energy absorption layer). C1, C2, Ct: Wafer cassette; D: Distance (an example of displacement); D1: First element layer; D2: Second element layer; E: Energy absorption layer; J: Adhesive layer (an example of energy absorption layer); L, L1, L2: Laser light; S101~S108: Steps; S201~S207: Steps; T: Overlapping substrate; W1: Upper wafer (first substrate) (first wafer) (an example of substrate and the other substrate); W1j: Bonding surface; W1n: Non-bonding surface; W2: Lower wafer (second substrate) (second wafer) (an example of substrate and the other substrate); W2j: Bonding surface; W2n: Non-bonding surface; X, Y, Z: Axis [Figure 1] Figure 1 is a schematic top view showing the configuration of the peeling system according to the embodiment. [Figure 2] Figure 2 is a schematic cross-sectional view of the overlapping substrate according to the embodiment. [Figure 3] Figure 3 is a schematic diagram showing the configuration of the peeling apparatus according to the embodiment. [Figure 4] Figure 4 is a flowchart showing the processing sequence of the peeling process performed by the peeling apparatus according to the embodiment. [Figure 5] Figure 5 is a diagram showing an example of the distance shift from the laser displacement meter to the upper wafer. [Figure 6] Figure 6 is a schematic cross-sectional view of the overlapping substrate according to modified example 1 of the embodiment. [Figure 7] Figure 7 is a schematic diagram showing the configuration of the peeling apparatus according to modified example 1 of the embodiment. [Figure 8] Figure 8 is a flowchart showing the processing sequence of the peeling process performed by the peeling apparatus according to modified example 1 of the embodiment. [Figure 9] Figures 9(a) to (b) are diagrams used to explain the peeling process according to modified example 2 of the embodiment. [Fig. 10] Fig. 10(a)~(b) are diagrams illustrating the peeling process according to variation 3 of the embodiment. [Fig. 11] Fig. 11(a)~(c) are diagrams illustrating the peeling process according to variation 4 of the embodiment. 5: Peeling device (an example of a substrate processing device) 40: Processing Unit 41: Heating Chamber 42: Fixed Section 43: Cover part 43a: Window components 44: Support Components 45: Adsorption surface 45a: Inhalation tube 45b: Inhalation device 46: Drive mechanism 47: Support Components 48: Heater 60: Measurement Unit 61: Laser displacement meter 62: Distance measuring unit 100: Processing Room D: Distance (an example of displacement) L1: Laser light T: Overlapping substrate W1: Upper wafer (first substrate) (first wafer) (an example of a substrate and the other substrate) W2: Lower wafer (second substrate) (second wafer) (an example of a substrate and one of the substrates) X, Y, Z: Axes

Claims

1. A substrate processing apparatus comprising: a processing unit for holding one of the substrates while applying at least one of heat energy and light energy to the energy absorption layer of an overlapping substrate formed by forming an energy absorption layer between a pair of substrates, thereby peeling off the other substrate; a measuring unit for measuring the displacement of the other substrate in the processing unit; and a control unit for controlling each unit; the control unit determining whether the other substrate has been peeled off based on the displacement of the other substrate.

2. The substrate processing apparatus as described in claim 1, wherein, When the displacement of the other substrate changes rapidly, the control unit determines that the other substrate has been peeled off.

3. The substrate processing apparatus as described in claim 1 or 2, wherein, The measuring unit measures the displacement without contacting the substrate of the other party.

4. The substrate processing apparatus as described in claim 1 or 2, wherein, The measuring unit has at least one of a laser displacement meter, an ultrasonic displacement meter, and a camera.

5. The substrate processing apparatus as described in claim 1 or 2, wherein, The processing unit includes: a heating chamber, which is a sealed structure, for applying heat to the energy absorption layer; and a measuring unit for measuring the displacement of the other substrate from outside the heating chamber.

6. The substrate processing apparatus as claimed in claim 1 or 2, wherein, The processing unit includes: a laser irradiation section that applies light energy to the energy absorption layer; and a measurement unit configured in the same environment as the laser irradiation section.

7. A substrate processing method, comprising: an application step, wherein, for an overlapping substrate formed by forming an energy absorption layer between a pair of substrates, one of the substrates is held while at least one of thermal energy and light energy is applied to the energy absorption layer; a measurement step, wherein, during the application step, the displacement of the other substrate is measured; and a determination step, wherein, based on the displacement of the other substrate, it is determined whether the other substrate has been peeled off.

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