Processing system and processing method

Abstract

Disclosed is a processing system for processing a polymerization substrate in which a first substrate and a second substrate are bonded. This processing system comprises: a laser irradiation device for processing the polymerization substrate; and a conveyance device for conveying the polymerization substrate. The laser irradiation device is provided with a detection mechanism for detecting that at least a part of the polymerization substrate protrudes from a horizontal direction reference position at a delivery position where the polymerization substrate is transferred to and from the conveyance device.

Description

Processing system and processing method

[0001] The present disclosure relates to a processing system and a processing method.

[0002] Patent Document 1 discloses a method for transferring a semiconductor element formed on a surface of a semiconductor substrate having a separation oxide film and a semiconductor element to a destination substrate. The method described in Patent Document 1 includes a step of irradiating the back surface of the semiconductor substrate with light to locally heat the separation oxide film, and a step of causing separation in the separation oxide film and / or at the interface between the separation oxide film and the semiconductor substrate, thereby transferring the semiconductor element to the destination substrate.

[0003] Japanese Patent Application Laid-Open No. 2007-220749

[0004] The technology disclosed herein prevents the upper substrate from unintentionally falling off the lower substrate after irradiation with laser light and before separation of the substrates, when separating the substrates using a separation surface formed by irradiation with laser light as a base point.

[0005] One aspect of the present disclosure is a processing system for processing a laminated substrate formed by bonding a first substrate and a second substrate, the processing system including a laser irradiation device for processing the laminated substrate and a transport device for transporting the laminated substrate, the laser irradiation device including a detection mechanism for detecting whether at least a portion of the laminated substrate protrudes from a horizontal reference position at a transfer position where the laminated substrate is transferred between the laser irradiation device and the transport device.

[0006] According to the present disclosure, when separating substrates using a separation surface formed by irradiation with laser light as a base point, it is possible to prevent the upper substrate from unintentionally falling from the lower substrate after irradiation with laser light and before the substrates are separated.

[0007] 1 is a side view showing an outline of the configuration of a laminated wafer to be processed; FIG. 2 is a plan view showing an outline of the configuration of a processing system; FIG. 3 is a side view showing an outline of the configuration of a transport device; FIG. 4 is a plan view showing an outline of the configuration of a transport arm; FIG. 5 is a plan view showing an outline of the arrangement of photoelectric sensors of a holding and detecting mechanism; FIG. 6 is a plan view showing an outline of the configuration of a laser irradiation device; FIG. 7 is a side view showing an outline of the configuration of the laser irradiation device at a processing position; FIG. 8 is a side view showing an outline of the configuration of the laser irradiation device at a delivery position; FIG. 9 is an explanatory diagram showing how laser light is irradiated onto a laser absorption layer; FIG. 10 is a cross-sectional view showing an example of a method for installing a detection mechanism; FIG. 11 is a side view showing an operation of a separation device; FIG. 12 is a flow diagram showing main steps of wafer processing in a laser irradiation device; FIG. 13 is an explanatory diagram showing an example of the operation of the detection mechanism; FIG. 14 is an explanatory diagram showing an example of the operation of the detection mechanism; FIG. 15 is a plan view showing an example of the arrangement of the detection mechanism; FIG. 16 is an explanatory diagram showing another example of the operation of the detection mechanism; FIG. 17 is an explanatory diagram explaining another wafer processing performed in the processing system;

[0008] In a semiconductor device manufacturing process, a device layer formed on the surface of a second semiconductor substrate is transferred to the first substrate in a laminated substrate formed by bonding a first substrate and a second semiconductor substrate together. The transfer of the device layer from the second substrate to the first substrate is performed by irradiating the interior of the laminated substrate with laser light to reduce the bonding strength between the first and second substrates, and then separating the second substrate from the first substrate.

[0009] The processing system for separating the substrates includes a laser irradiation device that irradiates the laminated substrate with laser light, a separation device that separates the first substrate and the second substrate, and a transport mechanism that transports the laminated substrate between the laser irradiation device and the separation device. Here, the laser irradiation device described above may have multiple fall prevention pins around the laminated substrate on the stage to prevent the second substrate from falling off the first substrate due to inertial forces associated with the transport operation after the laminated substrate is irradiated with laser light. However, when the laminated substrate is moved (lifted up) vertically on the stage to transfer it from the stage to the transport mechanism, there is a concern that the second substrate will climb over the fall prevention pins and fall.

[0010] The technology disclosed herein has been made in consideration of the above circumstances, and when separating substrates using a separation plane formed by irradiation with laser light as a base point, prevents the upper substrate from unintentionally falling off the lower substrate after irradiation with laser light and before separation of the substrates. In the following description, "separation" of the substrates refers to a state in which the second substrate can move horizontally relative to the first substrate. More specifically, this includes a state in which the bonding strength of the second substrate to the first substrate becomes zero and the second substrate moves independently and shifts relative to the first substrate, and a state in which the first substrate and the second substrate are still bonded but the bonding strength is reduced and the second substrate can move horizontally relative to the first substrate.

[0011] Hereinafter, a substrate processing system and processing method according to this embodiment will be described with reference to the drawings. In this specification and the drawings, elements having substantially the same functional configurations are designated by the same reference numerals, and redundant description will be omitted. In the following description, a "substrate" to be processed may be referred to as a "wafer" as an example.

[0012] In a processing system 1 according to this embodiment, which will be described later, processing is performed on a laminated wafer T in which a first wafer W and a second wafer S are bonded together, as shown in FIG. 1 . The laminated wafer T corresponds to a "laminated substrate" according to the technology of the present disclosure. Hereinafter, the surface of the first wafer W that is bonded to the second wafer S will be referred to as the front surface Wa, and the surface opposite the front surface Wa will be referred to as the back surface Wb. Similarly, the surface of the second wafer S that is bonded to the first wafer W will be referred to as the front surface Sa, and the surface opposite the front surface Sa will be referred to as the back surface Sb.

[0013] The first wafer W as the first substrate is a semiconductor wafer such as a silicon substrate. In this embodiment, the first wafer W has a substantially circular disk shape. On the surface Wa of the first wafer W, a device layer Dw and a surface film Fw are stacked in this order from the surface Wa side. The device layer Dw includes a plurality of devices. The surface film Fw may be, for example, an oxide film (THOX film, SiO ２ film, TEOS film), SiC film, SiCN film, adhesive, etc.

[0014] The second wafer S as the second substrate is also a semiconductor wafer such as a silicon substrate. In this embodiment, the second wafer S has a substantially circular disk shape. A laser absorption layer P, a device layer Ds, and a surface film Fs are laminated on the surface Sa of the second wafer S in this order from the surface Sa side. The laser absorption layer P absorbs laser light irradiated from the laser irradiation unit 110, which will be described later. The laser absorption layer P may be made of, for example, an oxide film (SiO ２ A laser absorption layer (film) is used, but is not particularly limited as long as it absorbs laser light. The device layer Ds and the surface film Fs are the same as the device layer Dw and the surface film Fw of the first wafer W, respectively. The surface film Fw of the first wafer W and the surface film Fs of the second wafer S are bonded together to form an overlapped wafer T. The position of the laser absorption layer P is not limited to the example shown in the figure, and it may be formed, for example, between the device layer Ds and the surface film Fs.

[0015] 2 , the processing system 1 has a configuration in which a load / unload block 2 and a processing block 3 are integrally connected. In the load / unload block 2, for example, cassettes C each capable of accommodating a plurality of first wafers W, second wafers S, or overlapped wafers T are loaded and unloaded between the load / unload block 2 and the outside. The processing block 3 includes various processing devices that perform desired processing on the first wafers W, second wafers S, or overlapped wafers T.

[0016] The carry-in / out block 2 is provided with a cassette mounting table 10 on which a plurality of, for example, three cassettes C are mounted. A transfer device 20 is provided on the X-axis positive side of the cassette mounting table 10. The transfer device 20 moves on a transfer path 21 extending in the Y-axis direction, and is configured to be able to transfer a first wafer W, a second wafer S, or a superimposed wafer T between the cassette C on the cassette mounting table 10 and a transition device 30 described below.

[0017] Furthermore, in the carry-in / out block 2, a transition device 30 and an inversion device 31 are stacked on the X-axis positive side of the transfer device 20. The transition device 30 temporarily stores the first wafer W, the second wafer S, or the overlapped wafer T for transfer to and from the processing block 3. The inversion device 31 inverts the top and bottom surfaces of the first wafer W, the second wafer S, or the overlapped wafer T. Note that the number and arrangement of the transition devices 30 and the inversion devices 31 are not limited to the example shown in the figure.

[0018] The processing block 3 is provided with a transport device 40, a laser irradiation device 50, a separation device 60, and a cleaning device 70. Note that, although Fig. 2 illustrates an example in which two laser irradiation devices 50, one separation device 60, and one cleaning device 70 are provided in the processing block 3, the numbers and arrangements of the laser irradiation devices 50, separation devices 60, and cleaning devices 70 are not limited to this.

[0019] The transfer device 40 is provided on the positive side of the X-axis from the transition device 30 and the reversing device 31. The transfer device 40 is disposed on a base 45 that is disposed on a transfer path 41 that extends in the X-axis direction. The transfer device 40 is configured to be movable on the transfer path 41 by a moving mechanism 40a (see FIG. 3) and to be rotatable integrally with the base 45 around a vertical axis (θ-axis) by a rotating mechanism 40b (see FIG. 3). This allows the transfer device 40 to transfer the first wafer W, the second wafer S, or the overlapped wafer T to the transition device 30 and the reversing device 31 in the carry-in / out block 2 and the laser irradiation device 50, the separation device 60, and the cleaning device 70 in the processing block 3.

[0020] As shown in FIG. 3 as an example, the transfer device 40 includes multiple, for example, three transfer arms 42a-42c (hereinafter, these may be collectively referred to as "transfer arms 42") that hold and transfer the first wafer W, the second wafer S, or the overlapped wafer T. The transfer arms 42 are stacked above a base 45 disposed on the transfer path 41. Each transfer arm 42 has a suction portion 43 (see also FIG. 4) on its holding surface for suction-holding the first wafer W, the second wafer S, or the overlapped wafer T. Each transfer arm 42 is configured to be movable horizontally, vertically, around a horizontal axis, and around a vertical axis. Additionally, each transfer arm 42 is configured to be movable in a direction extending or contracting relative to the base 45 by a sliding mechanism or an extension / contraction mechanism (not shown).

[0021] The three transfer arms 42a to 42c are stacked in this order from top to bottom. Each of the transfer arms 42a to 42c is independently rotatable about a vertical axis. At least one of the three transfer arms 42a to 42c (the upper transfer arm 42a in the illustrated example) has a holding surface provided with multiple, for example, four, guide pins 44 (see also FIG. 4). The guide pins 44 are arranged to surround the periphery of the overlapped wafer T when the transfer arm 42a holds the overlapped wafer T. The guide pins 44 prevent the second wafer S from falling off the first wafer W in the held overlapped wafer T due to inertial forces and the like associated with the transfer of the overlapped wafer T by the transfer device 40. Furthermore, at least one of the three transfer arms 42a to 42c (the middle transfer arm 42b in the illustrated example) has a suction portion 43 on its underside for suction-holding the first wafer W, the second wafer S, or the overlapped wafer T. In other words, the transfer arm 42b has a holding surface on the lower surface side. The transfer arm 42b suction-holds the second wafer S from above when the second wafer S is carried out from the separation device 60. The configuration of the transfer arm 42 is not limited to this embodiment, and any configuration may be used.

[0022] In this embodiment, the transfer device 40 has a hold detection mechanism 300 that detects the holding state of the overlapped wafer T held by the transfer arm 42. In one example, the hold detection mechanism 300 includes a plurality of, for example, four, sensors 310 (see also FIG. 5 ) and a frame F1 that supports the sensors 310. The sensors 310 may be photoelectric sensors, length measurement sensors, imaging mechanisms, or the like. The number and arrangement of the sensors 310 are not particularly limited. As shown in FIG. 3 , the frame F1 of the hold detection mechanism 300 is integral with a base 45, and is configured to be movable horizontally along the transfer path 41 together with the base 45 by a movement mechanism 40a, and to be movable around a vertical axis (θ-axis) together with the base 45 by a rotation mechanism 40b.

[0023] The holding detection mechanism 300 detects the holding state of the overlapped wafer T on the transfer arm 42 passing inside the frame F1, i.e., the misalignment of the second wafer S with respect to the first wafer W, when the transfer arm 42 transfers the overlapped wafer T to or from the various devices arranged in the processing block 3. The holding detection mechanism 300 also moves along the transfer path 41, following the transfer arm 42 holding the overlapped wafer T, integrally with the base 45, thereby detecting the holding state of the overlapped wafer T on the transfer arm 42 when the overlapped wafer T is transferred between the various devices arranged in the processing block 3. A detailed example of the operation of the holding detection mechanism 300 will be described later.

[0024] In the technology according to the present disclosure, the "holding state" of the overlapped wafer T detected by the holding detection mechanism 300 refers to the position of the overlapped wafer T held by the transfer arm 42 (particularly the transfer arm 42a) and the misalignment of the second wafer S with respect to the first wafer W. In this case, it is desirable that the detection of the position of the overlapped wafer T held by the transfer arm 42 and the detection of the misalignment of the second wafer S with respect to the first wafer W are configured to be capable of being detected separately.

[0025] The laser irradiation device 50 irradiates the inside of the overlapped wafer T, more specifically, the laser absorbing layer P of the second wafer S, with laser light to reduce the bonding strength at the interface between the second wafer S and the laser absorbing layer P. In the following description, the interface (in this embodiment, the interface between the second wafer S and the laser absorbing layer P) whose bonding strength has been reduced by this laser light irradiation may be referred to as a "separation surface." The laser irradiation device 50 has a control device 51, which will be described later.

[0026] 6 to 8, a transfer position A1 and a processing position A2 are set inside the laser irradiation device 50. The transfer position A1 is a position where the wafer is transferred between the transfer arm 42 of the transfer device 40 and a chuck 100 (described later), and is also a position where the outer edge of the overlapped wafer T is detected by a detection mechanism 120 (described later). The processing position A2 is a position where the overlapped wafer T (laser absorption layer P) is irradiated with laser light from a laser irradiation unit 110 (described later).

[0027] The laser irradiation device 50 has a chuck 100 that holds the overlapped wafer T on its upper surface. The chuck 100 has a wafer holding surface on its upper surface, and adsorbs and holds the entire back surface Wb of the first wafer W or a part of the inner side in the radial direction. Examples of the chuck 100 include an electrostatic chuck (ESC) and a vacuum chuck.

[0028] A chuck 100 serving as a substrate holder is supported by a slider table 102 via an air bearing 101. A rotation mechanism 103 is provided on the underside of the slider table 102. The rotation mechanism 103 incorporates, for example, a motor as a drive source. The chuck 100 is configured to be rotatable about the θ-axis (vertical axis) via the air bearing 101 by the rotation mechanism 103. The slider table 102 is configured to be movable between the transfer position A1 and the processing position A2 by a movement mechanism 104 provided on the underside of the slider table 102 along rails 106 provided on a base 105 and extending in the Y-axis direction. The drive source of the movement mechanism 104 is not particularly limited, but a linear motor, for example, is used.

[0029] 8, the chuck 100 is provided with lift pins 100a as a lifting mechanism for supporting and raising and lowering the overlapped wafer T from below. The lift pins 100a are inserted into through holes 100b formed through the chuck 100 and are configured to be able to freely protrude and retract from the upper surface (wafer holding surface) of the chuck 100. The lift pins 100a thereby support the back surface side (back surface Wb of the first wafer W) of the overlapped wafer T on the holding surface and move (lift up) it vertically above the chuck 100.

[0030] Furthermore, a plurality of, for example, three, drop prevention pins 107 are arranged radially around the periphery of the chuck 100 so as to surround the periphery of the overlapped wafer T held by the chuck 100. In one example, the drop prevention pins 107 are arranged on the upper surface of the slider table 102 and configured to be movable horizontally together with the chuck 100 by a moving mechanism 104. The drop prevention pins 107 prevent the second wafer S from dropping from the first wafer W when the second wafer S is unintentionally separated from the first wafer W during or after irradiation with laser light due to, for example, centrifugal force accompanying rotation of the chuck 100 or inertial force accompanying movement.

[0031] The arrangement of the fall prevention pin 107 is not particularly limited. Although not shown in the drawings, the fall prevention pin 107 may be arranged on the upper surface of the chuck 100 so as to be rotatable integrally with the chuck 100 by the rotation mechanism 103, for example.

[0032] A laser irradiation unit 110 is provided above the chuck 100 at the processing position A2. The laser irradiation unit 110 includes a laser head 111, an optical system 112, and a lens 113.

[0033] The laser head 111 has a laser oscillator (not shown) that oscillates a laser beam in pulses. This laser beam is a so-called pulse laser. In this embodiment, the laser beam is a CO ２ Laser light, CO ２ The wavelength of the laser light is, for example, 8.9 μm to 11 μm. The laser head 111 may also include other devices in addition to the laser oscillator, such as an amplifier.

[0034] The optical system 112 includes an optical element (not shown) that controls the intensity and position of the laser light, and an attenuator (not shown) that attenuates the laser light to adjust the output. The optical system 112 may also be configured to be able to control the branching of the laser light.

[0035] The lens 113 irradiates the overlapped wafer T held by the chuck 100 with laser light L. As shown in Fig. 9, the laser light L emitted from the laser irradiation unit 110 passes through the second wafer S and is irradiated onto the laser absorption layer P. The lens 113 may be configured to be freely movable up and down by an elevation mechanism (not shown).

[0036] 6, a detection mechanism 120 is disposed at a transfer position A1 where the overlapped wafer T is transferred to and from the transport device 40. The detection mechanism 120 includes, for example, a plurality of photoelectric sensors 121 (four in this embodiment), and a control unit 122. The control unit 122 may be provided in common to the four photoelectric sensors 121 as shown in the figure, or may be provided independently for each of the four photoelectric sensors 121.

[0037] 8, the photoelectric sensor 121 has a light-projecting unit 121a arranged above the overlapped wafer T held on the chuck 100 and a light-receiving unit 121b arranged below the overlapped wafer T held on the chuck 100. The light-projecting unit 121a emits a beam B toward the light-receiving unit 121b. The light-receiving unit 121b receives the beam B from the light-projecting unit 121a. The four photoelectric sensors 121 are arranged at positions where all four light-receiving units 121b can receive the beam B when the overlapped wafer T is normally held on the chuck 100, that is, when the horizontal misalignment of the second wafer S with respect to the first wafer W is within an allowable range (a range in which the second wafer S will not fall unintentionally).

[0038] The method of installing the photoelectric sensor 121 (light-projecting unit 121a and light-receiving unit 121b) in the laser irradiation device 50 is not particularly limited, and for example, the light-projecting unit 121a and the light-receiving unit 121b may be fixedly disposed on the top and bottom surfaces of the laser irradiation device 50, respectively. Alternatively, as shown in FIG. 10 , for example, a frame F2 for fixing and disposing the photoelectric sensor 121 may be constructed inside the laser irradiation device 50. Furthermore, for example, the photoelectric sensor 121 does not necessarily have to be fixedly disposed at the transfer position A1, and may be configured integrally with the slider table 102 so that it can move between the processing position A2 together with the overlapped wafer T held by the chuck 100.

[0039] The control unit 122 detects whether the second wafer S is misaligned in the horizontal direction with respect to the first wafer W, in other words, whether the second wafer S has been unintentionally separated from the first wafer W, depending on the reception state of the beam B at the light receiving units 121b. Specifically, if all four light receiving units 121b can receive the beam B, it is determined that the overlapped wafer T is properly held on the chuck 100, and if any of the light receiving units 121b cannot receive the beam B, it is determined that the overlapped wafer T is not properly held on the chuck 100.

[0040] The control unit 122 may be provided independently of the detection mechanism 120 in this manner, or may be included in the control device 80 described below. In other words, the control device 80 may have a function as a determination unit according to the technology of the present disclosure.

[0041] In this embodiment, the detection mechanism according to the technology of the present disclosure will be described as a "photoelectric sensor 121" having a light-emitting unit 121a and a light-receiving unit 121b, but the configuration of the detection mechanism is not limited to this as long as it can at least detect whether the overlapped wafer T is properly held on the chuck 100. Specifically, for example, the detection mechanism according to the technology of the present disclosure may be a length measuring sensor (displacement meter) that acquires position information of the second wafer S by measuring at least the distance to the second wafer S, or may be an imaging mechanism that images the overlapped wafer T (second wafer S) from above.

[0042] In addition, in this embodiment, an example will be described in which the photoelectric sensor 121 according to the technology disclosed herein is arranged above and below the chuck 100 at the transfer position A1, but the photoelectric sensor 121 may also be arranged to the side of the chuck 100 as long as it can acquire the position of at least the second wafer S on the chuck 100.

[0043] A transfer pad 130 may also be provided above the chuck 100 at the transfer position A1. The transfer pad 130 is configured to be freely raised and lowered by an elevation mechanism (not shown). The transfer pad 130 has an adsorption surface on its underside for adsorbing and holding the first wafer W. When the detection mechanism 120 determines that the overlapped wafer T is not properly held on the chuck 100, the transfer pad 130 transfers the second wafer S between the chuck 100 and the transfer arm 42. Details of the operation of the transfer pad 130 will be described later.

[0044] The separating device 60 separates the second wafer S from the first wafer W using the interface between the second wafer S and the laser absorption layer P, which serves as a separation surface and whose bonding strength has been reduced by the laser irradiation device 50, as a base point.

[0045] 11 , the separation apparatus 60 includes a suction chuck 200 as a first suction-holding unit that suction-holds the back surface Wb of the first wafer W from below, and a suction pad 210 as a second suction-holding unit that suction-holds the back surface Sb of the second wafer S from above. The suction chuck 200 is provided with lift pins 200a for supporting the first wafer W from below and lifting and lowering it. The lift pins 200a as a second lifting mechanism are inserted through through holes 200b formed through the suction chuck 200 and are configured to be freely raised and lowered. In the separation apparatus 60, with the suction pad 210 suction-holding the second wafer S as shown in FIG. 11 , the second wafer S is separated from the laser absorption layer P by raising the suction pad 210 or lowering the suction chuck 200.

[0046] Furthermore, a plurality of, for example, three, fall prevention pins 220 are provided around the periphery of the overlapped wafer T held by the suction chuck 200 of the separation apparatus 60. The fall prevention pins 220 may be provided on the upper surface of the suction chuck 200 or may be arranged on a member other than the suction chuck 200, such as the floor of the separation apparatus 60, as long as they are provided so as to surround the periphery of the overlapped wafer T. The fall prevention pins 220 correspond to "separation fall prevention pins" according to the technology of the present disclosure. The fall prevention pins 220 preferably have a length such that their tips are positioned higher than the upper surface of the overlapped wafer T held by the suction chuck 200, and more preferably have a length such that they can surround the periphery of the overlapped wafer T even when moved vertically by the lift pins 200a (i.e., their tips are positioned higher than the upper surface of the overlapped wafer T, preventing the second wafer S from falling). The fall prevention pins 220 prevent the second wafer S from falling from the first wafer W when the second wafer S is unintentionally separated from the first wafer W, for example, when transferring the overlapped wafer T from the transport device 40 to the suction chuck 200 or when the overlapped wafer T is moved vertically by the lifting pins 200a.

[0047] The configuration of the separation device 60 is not limited to this, and any configuration may be used as long as it can separate the second wafer S from the first wafer W. For example, although the illustrated example shows a case in which the suction pad 210 holds the entire back surface Sb of the second wafer S, the suction pad 210 may hold only a portion of the back surface Sb. Alternatively, the number of suction pads 210 is not particularly limited, and multiple suction pads 210 may simultaneously suction-hold different positions on the back surface Sb. In this case, the multiple suction pads 210 may hold the central portion and the outer periphery of the second wafer S, respectively, or the central portion and / or the outer periphery may be divided radially so that the second wafer S is held at multiple locations radially.

[0048] The cleaning apparatus 70 cleans the first wafer W and the second wafer S separated by the separation apparatus 60. The configuration of the cleaning apparatus 70 is not particularly limited. In this embodiment, an example is described in which only one cleaning apparatus 70 common to the first wafer W and the second wafer S is provided in the processing system 1. However, a first cleaning apparatus for cleaning the first wafer W and a second cleaning apparatus for cleaning the second wafer S may be provided independently in the processing system 1.

[0049] The processing system 1 described above is provided with at least one control device serving as a control unit, namely, in this embodiment, a control device 51 and a control device 80. The control device 51 individually controls the operation of the laser irradiation device 50. The control device 80 oversees wafer processing in the processing system 1. The control devices 51 and 80 process computer-executable instructions that cause the processing system 1 to perform various processes described in this disclosure. The control devices 51 and 80 may be configured to control each element of the processing system 1 to perform the various processes described herein. In one embodiment, some or all of the control devices 51 and 80 may be included in the processing system 1. The control devices 51 and 80 may include a processing unit, a storage unit, and a communication interface. The control devices 51 and 80 are realized, for example, by a computer. The processing unit may be configured to read a program that provides logic or routines that enable various control operations from the storage unit and execute the read program to perform various control operations. This program may be stored in the storage unit in advance or may be acquired via the medium H when needed. The acquired program is stored in the storage unit and read from the storage unit by the processing unit for execution. The medium H may be any of various computer-readable storage media or a communication line connected to the communication interface. The storage medium H may be temporary or non-temporary. The processing unit may be a central processing unit (CPU) or one or more circuits. The storage unit may include a random access memory (RAM), a read-only memory (ROM), a hard disk drive (HDD), a solid state drive (SSD), or a combination thereof. The communication interface may communicate with the processing system 1 via a communication line such as a local area network (LAN).

[0050] Next, a description will be given of wafer processing performed using the processing system 1 configured as described above. In this embodiment, the first wafer W and the second wafer S are bonded together in a bonding apparatus (not shown) external to the processing system 1 to form an overlapped wafer T in advance.

[0051] First, a cassette C containing a plurality of overlapping wafers T is placed on the cassette table 10 of the carry-in / out block 2 .

[0052] Next, the transfer device 20 removes the overlapped wafer T from the cassette C, and transfers it to the laser irradiation device 50 via the transition device 30 and the transfer device 40 .

[0053] The overlapped wafer T transferred to the laser irradiation device 50 is first transferred from the transfer arm 42 of the transfer device 40 to the chuck 100 positioned at the transfer position A1 (S1 in FIG. 12 ). As an example, the transfer arm 42c holding the overlapped wafer T is first positioned above the chuck 100 waiting at the transfer position A1. Next, the lift pins 100a of the chuck 100 are moved vertically to protrude from the upper surface (wafer holding surface) of the chuck 100. Next, the transfer arm 42c holding the overlapped wafer T is lowered, thereby transferring the overlapped wafer T on the transfer arm 42c to the tips of the lift pins 100a. Next, the transfer arm 42c that has transferred the overlapped wafer T is retracted from above the chuck 100. Finally, the lift pins 100a onto which the overlapped wafer T has been transferred are lowered, and the tip of the lift pins 100a is positioned below the wafer holding surface of the chuck 100, thereby transferring the overlapped wafer T on the lift pins 100a to the wafer holding surface of the chuck 100.

[0054] In the above example, the overlapping wafer T is transferred from the transport arm 42c to the lift pins 100a by lowering the transport arm 42c, but instead, the overlapping wafer T may be transferred from the transport arm 42c to the lift pins 100a by raising the lift pins 100a.

[0055] Next, the detection mechanism 120 determines whether the overlapped wafer T is properly held on the chuck 100 (eccentricity determination: S2 in FIG. 12 ). Specifically, after the overlapped wafer T is transferred from the transfer arm 42 to the chuck 100, beams B are irradiated from the light-projecting portions 121 a of a plurality of photoelectric sensors 121 (four in this embodiment) arranged at the transfer position A1.

[0056] 13, when reception of beam B is detected by all four light receiving portions 121b, it is determined that the overlapped wafer T is properly held on the chuck 100, more specifically, that the overlapped wafer T has been transferred to the chuck 100 at least within the allowable transport error of the transport arm 42, and the process proceeds to the next process in the laser irradiation device 50. In this embodiment, the chuck 100 is allowed to move to the processing position A2.

[0057] On the other hand, if beam B is not received by at least one of the four light-receiving units 121b, as shown in FIG. 14, it is determined that the overlapped wafer T is held eccentrically in the direction of the light-receiving unit 121b where beam B was not detected. That is, it is detected that the overlapped wafer T is protruding from the horizontal reference position in at least a portion of the overlapped wafer T corresponding to the light-receiving unit 121b where beam B was not detected. Note that, in this embodiment, the "horizontal reference position" for the eccentricity is a position within a desired allowable transfer error range from the planned horizontal placement position on the chuck 100. However, this is not limited thereto, and a position within a desired error range based on a desired configuration can be preset as the reference position depending on the device configuration and the process content. In this case, the overlapped wafer T may be transferred from the chuck 100 to the transfer arm 42 again, and the overlapped wafer T may be repositioned relative to the chuck 100 (S2-1 in FIG. 12). Alternatively, if it is determined that the transfer arm 42 cannot normally transfer the overlapped wafer T to the chuck 100, the overlapped wafer T may be manually retrieved from the laser irradiation device 50 (S20 in FIG. 12 ), and wafer processing may be stopped in the processing system 1. At this time, further calibration may be performed to improve the transfer accuracy of the transfer device 40.

[0058] The eccentricity determination by the detection mechanism 120 (S2 in FIG. 12) may be performed after the first wafer W of the overlapped wafer T is attracted and held by the chuck 100 (S1 in FIG. 12) as described above, but may also be performed, for example, after the transfer arm 42c holding the overlapped wafer T is positioned above the chuck 100 and before the overlapped wafer T is transferred to the lift pins 100a. Alternatively, for example, the determination may be performed after the overlapped wafer T is transferred from the transfer arm 42c to the lift pins 100a and before the lift pins 100a holding the overlapped wafer T are lowered (to transfer the overlapped wafer T to the chuck 100).

[0059] When it is determined that the overlapped wafer T is properly held on the chuck 100, the moving mechanism 104 moves the chuck 100 to the processing position A2. Then, as shown in FIG. 9, the laser irradiating unit 110 irradiates the laser absorbing layer P with the laser light L(CO ２ The laser absorption layer P is irradiated with pulsed laser light to reduce the bonding strength at the interface between the laser absorption layer P and the second wafer S (laser treatment: S3 in FIG. 12).

[0060] More specifically, the overlapped wafer T held by the chuck 100 is rotated by the rotation mechanism 103, and the overlapped wafer T is moved in the Y-axis direction by the movement mechanism 104 while being irradiated with pulsed laser light L. As a result, the irradiation position of the laser light L is moved from the outer side to the inner side in the radial direction relative to the laser absorbing layer P, and as a result, the laser light L is irradiated onto the entire surface of the laser absorbing layer P.

[0061] The method of irradiating the laser absorbing layer P with the laser light L is not particularly limited as long as the entire surface of the laser absorbing layer P is irradiated with the laser light L and the bonding strength can be reduced over the entire surface of the second wafer S and the laser absorbing layer P. For example, the irradiation position of the laser light L may be arranged spirally in a planar view with respect to the laser absorbing layer P, or may be arranged in a ring shape concentric with the laser absorbing layer P in a planar view. Alternatively, the laser irradiation unit 110 may be moved horizontally with respect to the overlapping wafer T to scan the irradiation position of the laser light L over the entire surface of the laser absorbing layer P or over a part of the radial direction.

[0062] Furthermore, for example, in order to improve the throughput of the laser irradiation device 50, the laser light L may be split by the optical system 112 described above, and the laser light L may be irradiated onto a plurality of points on the laser absorption layer P simultaneously.

[0063] After the bonding strength of the second wafer S and the laser absorption layer P is reduced over the entire surface by irradiation with the laser light L, the chuck 100 (superimposed wafer T) is then moved to the transfer position A1 by the moving mechanism 104 (S4 in FIG. 12).

[0064] Subsequently, at the transfer position A1, it is detected whether the laser-processed overlapped wafer T is properly held by the chuck 100 (separation determination (1): S5 in FIG. 12). Specifically, after the chuck 100 is moved from the processing position A2 to the transfer position A1 by the moving mechanism 104, the beam B is irradiated from the light-emitting portions 121a of the multiple (four in this embodiment) photoelectric sensors 121 arranged at the transfer position A1. In this case, the first wafer W is preferably held by suction on the chuck 100.

[0065] 13, when reception of the beam B is detected by all four light receiving portions 121b, it is determined that the overlapped wafer T is properly held on the chuck 100. More specifically, it is determined that at least the horizontal misalignment of the second wafer S relative to the first wafer W is within an allowable range (a range within which the overlapped wafer T will not fall unintentionally). Thereafter, the laser irradiation device 50 proceeds to the next operation. In this embodiment, the lift pins 100a are allowed to move (lift up) the overlapped wafer T on the holding surface of the chuck 100 in the vertical direction.

[0066] On the other hand, if at least one of the four light-receiving units 121b fails to receive the beam B, it is determined that the second wafer S unintentionally separated due to, for example, inertial force accompanying the movement of the chuck 100 from the processing position A2 to the transfer position A1, and that the second wafer S moved horizontally relative to the first wafer W by an amount greater than the allowable range. That is, at least a portion of the overlapped wafer T corresponding to the light-receiving unit 121b where reception of the beam B was not detected is detected to have protruded from the horizontal reference position. In this case, the portion of the overlapped wafer T refers to a portion of the second wafer S that has protruded from the horizontal reference position due to separation and displacement of the second wafer S relative to the first wafer W. In this embodiment, the "horizontal reference position" associated with the displacement due to separation is a position within a desired allowable transport error range from the planned horizontal placement position on the chuck 100. However, this is not limited to this, and a position within a desired error range based on a desired configuration can be preset as the reference position depending on the device configuration and the process content. For example, the position of the first wafer W in contact with the chuck 100 may be used as a horizontal reference position to detect deviation of the second wafer S due to separation from the first wafer W. In this case, it is determined that there is a risk of the second wafer S falling from the first wafer W, and the overlapped wafer T is manually retrieved from the laser irradiation device 50 (S20 in FIG. 12 ), for example, and wafer processing in the processing system 1 is stopped.

[0067] When it is determined that the overlapped wafer T is properly held by the chuck 100, the lift pins 100a are then used to vertically move (lift up) the overlapped wafer T on the holding surface (S6 in FIG. 12 ). The height of the overlapped wafer T after being lifted up is, for example, a height at which the overlapped wafer T can be properly transferred between the transfer arm 42a of the transfer device 40 and the chuck 100, more specifically, a height at which the transfer arm 42a can be inserted into the gap between the holding surface of the chuck 100 and the back surface Wb of the first wafer W.

[0068] Next, it is detected whether the amount of misalignment of the second wafer S relative to the first wafer W in the lifted-up overlapped wafer T is within an allowable range (separation determination (2): S7 in FIG. 12 ). Specifically, after the overlapped wafer T is lifted up by the lift pins 100a, beams B are irradiated from the light-projecting portions 121a of multiple (four in this embodiment) photoelectric sensors 121 arranged at the transfer position A1.

[0069] 13 , when reception of the beam B is detected by all four light receiving parts 121b, it is determined that at least the horizontal misalignment amount of the second wafer S relative to the first wafer W is within an allowable range (a range within which unintentional dropping will not occur), and the process proceeds to the next operation in the laser irradiation device 50. In this embodiment, the transfer arm 42a of the transfer device 40 is allowed to enter the laser irradiation device 50.

[0070] On the other hand, if at least one of the four light receiving units 121b fails to receive the beam B, it is determined that the second wafer S has unintentionally separated, for example, due to inertial force or the like associated with lift-up, and that the second wafer S has moved horizontally with a deviation greater than the allowable range relative to the first wafer W. In this case, it is determined that there is a risk of the second wafer S falling from the first wafer W, and the overlapped wafer T is manually retrieved from the laser irradiation device 50 (S20 in FIG. 12 ), for example, and wafer processing in the processing system 1 is stopped.

[0071] If it is determined that the misalignment of the second wafer S relative to the first wafer W is within the allowable range, the transport arm 42a of the transport device 40 is then advanced into the laser irradiation device 50 and inserted into the gap between the holding surface of the chuck 100 and the back surface of the overlapping wafer T (back surface Sb of the second wafer S) (S8 in Figure 12).

[0072] Subsequently, after the transfer arm 42a is inserted into the gap between the chuck 100 and the overlapped wafer T, it is detected whether the amount of misalignment of the second wafer S with respect to the first wafer W is within an allowable range (separation determination (3): S9 in FIG. 12). Specifically, after the transfer arm 42a is inserted, beams B are irradiated from the light-projecting portions 121a of the plurality of photoelectric sensors 121 (four in this embodiment) arranged at the transfer position A1.

[0073] 13, when reception of beam B is detected by all four light receiving parts 121b, it is determined that at least the horizontal misalignment amount of the second wafer S relative to the first wafer W is within an allowable range (a range within which unintentional dropping will not occur), and the process proceeds to the next operation in the laser irradiation device 50. In this embodiment, the overlapped wafer T held at the tip of the lift pins 100a is allowed to be transferred to the transfer arm 42a.

[0074] On the other hand, if at least one of the four light receiving units 121b fails to receive the beam B, it is determined that the second wafer S unintentionally separated during insertion of the transfer arm 42a and moved horizontally with a deviation greater than the allowable range relative to the first wafer W. In this case, it is determined that there is a risk of the second wafer S falling from the first wafer W, and the overlapped wafer T is manually retrieved from the laser irradiation device 50 (S20 in FIG. 12 ), for example, and wafer processing in the processing system 1 is stopped.

[0075] If it is determined that the misalignment of the second wafer S relative to the first wafer W is within the tolerance, the overlapped wafer T held at the tips of the lift pins 100a is then transferred to the transfer arm 42a (S10 in FIG. 12). Specifically, the transfer arm 42a inserted between the chuck 100 and the overlapped wafer T is raised, thereby transferring the overlapped wafer T held at the tips of the lift pins 100a to the holding surface of the transfer arm 42a. At this time, as shown in FIG. 4, the holding surface of the transfer arm 42a is provided with a plurality of guide pins 44, for example, four, and the position of the transfer arm 42a is adjusted so that the overlapped wafer T is held within these four guide pins 44. Next, the lift pins 100a that have transferred the overlapped wafer T are lowered and retracted into the through holes 100b formed in the chuck 100.

[0076] In the above example, the overlapped wafer T is transferred from the lift pins 100a to the transfer arm 42a by raising the transfer arm 42, but alternatively, the overlapped wafer T may be transferred from the lift pins 100a to the transfer arm 42 by lowering the lift pins 100a.

[0077] Subsequently, after the transfer arm 42a receives the overlapped wafer T, it is detected whether the amount of misalignment of the second wafer S with respect to the first wafer W is within an allowable range (separation determination (4): S11 in FIG. 12 ). Specifically, after the overlapped wafer T is delivered to the transfer arm 42a, beams B are irradiated from the light-projecting portions 121a of the plurality of photoelectric sensors 121 (four in this embodiment) arranged at the delivery position A1.

[0078] When reception of the beam B is detected by all four light receiving units 121b, it is determined that at least the horizontal misalignment of the second wafer S with respect to the first wafer W is within an allowable range (a range within which the second wafer S will not fall unintentionally). In this embodiment, the transfer arm 42a (the laser-processed laminated wafer T) is then permitted to be unloaded from the laser irradiation device 50. Then, the transfer arm 42a (the laminated wafer T) is unloaded from the laser irradiation device 50 (S12 in FIG. 12 ).

[0079] Thereafter, the laser-processed overlapped wafer T is unloaded from the laser irradiation device 50 by the transfer arm 42a. Subsequently, the next unlaser-processed overlapped wafer T is loaded into the laser irradiation device 50 by the transfer arm 42c and held by suction on the chuck 100 (return to S1 in FIG. 12 ). The timing for loading the next unlaser-processed overlapped wafer T into the laser irradiation device 50 is not limited to after the laser-processed overlapped wafer T has been unloaded from the laser irradiation device 50. For example, when the above-described transfer of the overlapped wafer T from the lift pins 100a to the transfer arm 42 (S10 in FIG. 12 ) is performed, the next unlaser-processed overlapped wafer T may be placed above the chuck 100 in advance. In this case, the next unlaser-processed overlapped wafer T may be held on the chuck 100 when the lift pins 100a are lowered (retracted into the through holes 100b).

[0080] On the other hand, if at least one of the four light receiving units 121b fails to receive the beam B, it is determined that the second wafer S unintentionally separated during insertion of the transfer arm 42a and moved horizontally by an amount of deviation exceeding the allowable range relative to the first wafer W. In this case, it is determined that there is a risk of the second wafer S falling from the first wafer W, and the overlapped wafer T is manually retrieved from the transfer arm 42a (S20 in FIG. 12 ), for example, and wafer processing in the processing system 1 is stopped.

[0081] The laminated wafer T, which has been carried out of the laser irradiation device 50 by the transfer arm 42a, is then transferred by the transfer device 40 to the separation device 60. In the separation device 60, as shown in Fig. 11 , the second wafer S is completely separated from the first wafer W, using the interface between the second wafer S and the laser absorption layer P, whose bonding strength has been reduced by the irradiation of the laser light L, as a separation surface.

[0082] Specifically, as described above, the back surface Wb of the first wafer W is suction-held by the suction chuck 200, and further, the back surface Sb of the second wafer S is suction-held by the suction pad 210. Thereafter, while the suction pad 210 is suction-holding the second wafer S, the suction pad 210 is raised or the suction chuck 200 is lowered to separate the first wafer W and the second wafer S. At this time, because the bonding strength at the interface between the laser absorption layer P and the second wafer S is reduced by the irradiation of the laser light L as described above, the second wafer S can be separated without applying a large load.

[0083] When separating the first wafer W and the second wafer S in the separation apparatus 60, the pressure applied when the suction pads 210 suction-hold the second wafer S may be measured, and a change in this pressure may be detected to detect misalignment of the second wafer S. Specifically, for example, in the case where a plurality of suction pads 210 are provided as described above, if the pressure detected by any of the suction pads 210 corresponding to the outer periphery of the second wafer S decreases, it is determined that the second wafer S is not being suctioned by the suction pad 210 corresponding to that outer periphery. In this case, it can be determined that the second wafer S is misaligned in the direction opposite to the arrangement direction of the suction pad 210. Furthermore, even in the case where only one suction pad 210 is provided, if the suction pad 210 covers the entire surface of the second wafer S, even up to the outer periphery, it is possible to similarly determine misalignment of the second wafer S by detecting the pressure.

[0084] The separated second wafer S is then transferred from the suction pad 210 to the transfer arm 42b or 42c of the wafer transfer device 22 and transferred to the inverting device 31. Then, in the inverting device 31, the second wafer S is turned so that the front surface Sa faces upward, and then transferred to the cleaning device 70. In the cleaning device 70, the front surface Sa, which is the surface separated from the first wafer W, is cleaned. Note that in the cleaning device 70, the back surface Sb may be cleaned together with the front surface Sa. Alternatively, separate cleaning units may be provided for cleaning the front surface Sa and the back surface Sb, respectively.

[0085] Thereafter, the second wafer S that has been cleaned by the cleaning device 70 is carried out of the cleaning device 70 by the transfer device 40 and is placed in the cassette C on the cassette mounting table 10 via the transition device 30 and the transfer device 20 .

[0086] Meanwhile, the first wafer W from which the second wafer S has been separated in the separating device 60 is transferred from the suction chuck 200 to the transfer arm 42c and transferred to the cleaning device 70. This transfer by the transfer arm 42c may be performed simultaneously with or independently of the transfer of the second wafer S by the transfer arm 42a. In the cleaning device 70, the front surface Wa of the first wafer W, which is the surface separated from the second wafer S, specifically the surface of the laser absorbing layer P, is cleaned. Note that in the cleaning device 70, the back surface Wb of the first wafer W may be cleaned together with the surface of the laser absorbing layer P. Furthermore, separate cleaning units may be provided for cleaning the front surface of the laser absorbing layer P and the back surface Wb of the first wafer W, respectively. Furthermore, cleaning of the first wafer W may be performed simultaneously with cleaning of the second wafer S or independently.

[0087] Thereafter, the first wafer W cleaned by the cleaning device 70 is transferred out of the cleaning device 70 by the transfer device 40 and is placed in the cassette C on the cassette mounting table 10 via the transition device 30 and the transfer device 20 .

[0088] Thereafter, when the processing of all the overlapped wafers T accommodated in the cassette C is completed, the series of wafer processing in the processing system 1 is completed.

[0089] As described above, according to the processing system 1 relating to the technique of the present disclosure, in the laser irradiation device 50 that performs laser processing of the overlapped wafer T, the detection mechanism 120 is provided at the transfer position A1 where the overlapped wafer T is transferred to and from the outside of the laser irradiation device 50, thereby checking whether the second wafer S is misaligned in the horizontal direction relative to the first wafer W. In particular, according to this embodiment, the misalignment of the second wafer S is checked even after the overlapped wafer T is lifted up by the lift pins 100a. As a result, even if the second wafer S is lifted above the protection range of the fall prevention pins 107, it is prevented from climbing over the fall prevention pins 107 and falling from the first wafer W.

[0090] Furthermore, in the laser irradiation apparatus 50 according to this embodiment, in addition to checking the misalignment of the second wafer S relative to the first wafer W at specific times (S2, S5, S7, S9, and S11 in FIG. 12 ), the detection mechanism 120 also performs detection when the overlapped wafer T is transferred to the chuck 100 (when the overlapped wafer T is loaded into the laser irradiation apparatus 50) (S2 in FIG. 12 ). This makes it possible to check not only the misalignment of the second wafer S relative to the first wafer W, but also the eccentricity of the overlapped wafer T relative to the chuck 100. That is, the detection by the detection mechanism 120 according to this embodiment detects that at least a portion of the overlapped wafer T protrudes from the horizontal reference position, and therefore makes it possible to detect the misalignment of the second wafer S relative to the first wafer W due to separation, and the eccentricity of the overlapped wafer T relative to the chuck 100.

[0091] In the above embodiment, the beam B is irradiated from the light-projecting unit 121a toward the light-receiving unit 121b at each of the specific timings described above to check for misalignment of the second wafer S with respect to the first wafer W. However, the timing of irradiation of the beam B is not necessarily limited to this, and for example, in the series of processes shown in Fig. 12, irradiation of the beam B may be continued, and only detection of the beam B by the light-receiving unit 121b may be performed at each of the specific timings described above.

[0092] Furthermore, in the above embodiment, the misalignment of the second wafer S relative to the first wafer W is confirmed at all of the above-mentioned specific timings. However, confirmation of the misalignment of the second wafer S relative to the first wafer W does not necessarily have to be performed at all of the above-mentioned timings, and may be omitted as appropriate at any timing depending on the purpose of wafer processing, the results of laser processing, etc. Therefore, in the technology disclosed herein, the misalignment of the second wafer S relative to the first wafer W is confirmed at at least one or more of the above-mentioned specific timings. Preferably, the misalignment of the second wafer S relative to the first wafer W is confirmed at all of the above-mentioned timings.

[0093] As described above, the number of photoelectric sensors 121 provided in the detection mechanism 120 is not particularly limited, and for example, three photoelectric sensors 121 may be arranged to surround the periphery of the overlapped wafer T at the transfer position A1 as shown in Fig. 15, or four photoelectric sensors 121 may be arranged as shown in Fig. 16. Increasing the number of photoelectric sensors 121 makes it possible to detect misalignment of the second wafer S and eccentricity of the overlapped wafer T with higher sensitivity.

[0094] In this case, the arrangement of the photoelectric sensors 121 is not particularly limited, but from the viewpoint of uniformly detecting the amount of misalignment of the second wafer S and the amount of eccentricity of the overlapped wafer T over the entire circumference in the circumferential direction, it is desirable that the multiple photoelectric sensors 121 be arranged at equal intervals in the circumferential direction. Furthermore, from the viewpoint of preventing the second wafer S from climbing over the fall prevention pins 107 and falling after being lifted up by the lift pins 100a, it is desirable that the multiple photoelectric sensors 121 be arranged inside the fall prevention pins 107 of the chuck 100, as shown in Figures 15 and 16. More specifically, as shown in Figures 15 and 16, it is desirable that a circle (see the dashed-dotted line in the figures) that passes through all of the fall prevention pins 107 in a plan view is set, and the arrangement of the photoelectric sensors 121 is determined so that all of the multiple photoelectric sensors 121 are included in the inner region of the circle (region X in the figures) in a plan view.

[0095] Similarly, the multiple photoelectric sensors 121 are desirably positioned inside the fall prevention pins 107 of the chuck 100, and also inside the multiple guide pins 44 arranged on the transport arm 42a in order to prevent the sensors from falling from the transport arm 42a.

[0096] Next, a method for checking the holding state of the overlapped wafer T on the transfer arm 42 using the above-described holding detection mechanism 300 (see FIGS. 3 and 5) will be described. As described above, the holding detection mechanism 300 includes a plurality of, for example, four sensors 310. The holding detection mechanism 300 detects the position of the overlapped wafer T held on the transfer arm 42 (particularly the transfer arm 42a) and whether or not the second wafer S is misaligned with respect to the first wafer W.

[0097] Specifically, for example, the position of the overlapped wafer T held by the transfer arm 42 can be detected by each of the multiple sensors 310. The position of the overlapped wafer T held by the transfer arm 42 can be detected by comparing the outer edge position detected by the sensor 310 with the outer edge position (horizontal reference position) that serves as a reference when the overlapped wafer T is normally held by the transfer arm 42. However, the horizontal reference position is not limited to the outer edge position when the overlapped wafer T is normally held, and can be preset as a position within a desired error range based on a desired configuration. Furthermore, for example, the height position of the backside of the overlapped wafer T (the backside Wb of the first wafer W) on the transfer arm 42 can be detected by each of the multiple sensors 310. If the backside position detected by the sensor 310 changes from the normal state, i.e., if the second wafer S is horizontally misaligned relative to the first wafer W and the height position of the front side Sa of the second wafer S is detected instead of the backside Wb of the first wafer W, it can be determined that the second wafer S is misaligned relative to the first wafer W.

[0098] Alternatively, for example, by configuring the device to be able to detect the radius or diameter (hereinafter referred to as "diameter") of the overlapped wafer T held by the transfer arm 42, if the detected diameter changes, it may be determined that the second wafer S is misaligned with respect to the first wafer W. More specifically, when the second wafer S is not misaligned, the diameter r1 of the overlapped wafer T is detected normally, as shown as an example in FIG. 17 . However, when the second wafer S is misaligned in the horizontal direction, as shown as an example in FIG. 18 , if the detected diameter increases by the amount of horizontal misalignment (α and β in the illustrated example), it may be determined that the second wafer S is misaligned with respect to the first wafer W. Alternatively, for example, the center point of the overlapped wafer T (second wafer S) may be calculated based on the detection result by the sensor 310, and if a deviation occurs in the center point, it may be determined that the second wafer S is misaligned with respect to the first wafer W.

[0099] As described above, the holding detection mechanism 300 according to this embodiment is configured to be movable horizontally together with the base 45 (transfer arm 42) and to be rotatable about the vertical axis together with the base 45, following the transfer arm 42. Therefore, the holding detection mechanism 300 can continuously detect the holding state of the overlapped wafer T on the transfer arm 42, even while the transfer arm 42 is transferring the overlapped wafer T from the laser irradiation device 50 to the separation device 60. In this case, if a misalignment of the second wafer S is detected during transfer, the transfer of the overlapped wafer T to the separation device 60 may be stopped.

[0100] In the above description, the laser light L is irradiated onto the laser absorption layer P formed between the first wafer W and the second wafer S, and the second wafer S is separated using the interface between the laser absorption layer P and the second wafer S as the separation surface. However, the wafer processing to which the detection mechanism 120 according to the technology of the present disclosure is applied is not limited to this. For example, instead of separating the second wafer S at the interface between the second wafer S and the laser absorption layer P, the technology of the present disclosure can also be applied to cases where the second wafer S is separated using, for example, the interface between the laser absorption layer P and the device layer Ds, or the interface between the surface film Fs and the surface film Fw as the separation surface. Furthermore, for example, the technology of the present disclosure can also be applied to cases where, as shown in FIG. 19 , the inside of the second wafer S is irradiated with laser light L along the surface direction to form a modified surface, and the back surface Sb side is separated using the modified surface as a base point to thin the second wafer S.

[0101] In the above embodiment, the laser absorbing layer P formed on the surface Sa of the second wafer S is irradiated with laser light, and the second wafer S is separated from the first wafer W using the interface between the second wafer S and the laser absorbing layer P as the separation plane. However, instead of this, for example, a release promoting layer (not shown) may be formed between the laser absorbing layer P and the second wafer S, and the second wafer S may be separated from the first wafer W using the interface between the release promoting layer and the laser absorbing layer P as the separation plane. In this case, it is desirable to adopt a release promoting layer such that the adhesion force between the release promoting layer and the laser absorbing layer P is at least smaller than the adhesion force between the second wafer S and the release promoting layer.

[0102] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The above-described embodiments may be omitted, substituted, or modified in various ways without departing from the scope and spirit of the appended claims. For example, the components of the above-described embodiments may be arbitrarily combined. Such an arbitrary combination naturally provides the functions and effects of each of the components involved in the combination, and also provides other functions and effects that are apparent to those skilled in the art from the description of this specification.

[0103] Furthermore, the effects described herein are merely descriptive or exemplary and are not limiting. In other words, the technology according to the present disclosure may achieve other effects that are apparent to those skilled in the art from the description of this specification, in addition to or in place of the above-described effects.

[0104] 1 Processing system 40 Transfer device 50 Laser irradiation device 120 Detection mechanism A1 Transfer position T Overlapped wafer W First wafer S Second wafer

Claims

1. A processing system for processing a polymerized substrate in which a first substrate and a second substrate are joined together, A laser irradiation apparatus for processing the polymerized substrate, The system includes a transport device for transporting the polymerized substrate, The laser irradiation device is, A processing system comprising a detection mechanism that detects whether at least a portion of the polymerized substrate extends beyond a horizontal reference position at a transfer position where the polymerized substrate is transferred to and from the transport device.

2. The laser irradiation device is, A substrate holding portion for holding the polymerized substrate, A lifting mechanism for moving the polymerized substrate vertically on the substrate holding section, A laser irradiation unit is provided at the processing position for processing the polymerized substrate, which irradiates laser light toward the polymerized substrate on the substrate holding unit, The processing system according to claim 1, further comprising a moving mechanism for moving the substrate holding portion between the delivery position and the processing position.

3. The aforementioned transport device is A transport arm having a holding surface for the polymerized substrate, The processing system according to claim 1, further comprising a holding detection mechanism for detecting that at least a portion of the polymerized substrate held by the transport arm is protruding from a horizontal reference position.

4. The aforementioned detection mechanism is A light-emitting unit that emits a beam, The processing system according to claim 2, comprising a plurality of photoelectric sensors each having a light-receiving unit for receiving the beam.

5. The substrate holding portion is equipped with a plurality of fall prevention pins arranged around the periphery of the polymerized substrate held by the substrate holding portion, The processing system according to claim 4, wherein the plurality of photoelectric sensors are arranged inside the plurality of fall prevention pins in a plan view.

6. The transport device includes a plurality of guide pins arranged around the periphery of the polymerized substrate when it is held in place. The processing system according to claim 4, wherein the plurality of photoelectric sensors are positioned inside the plurality of guide pins in a plan view when the transport device enters the transfer position.

7. The separation device is provided to separate the second substrate from the first substrate after laser processing by the laser irradiation device, The separation device is A first suction holding part that holds the first substrate from below, A second suction holding part that holds the second substrate from above, The processing system according to claim 1, further comprising a plurality of separation fall prevention pins arranged around the periphery of the polymerization substrate held by the first adsorption holding portion.

8. The processing system according to claim 7, wherein the tip of the separation fall prevention pin is positioned higher than the upper surface of the polymerization substrate held by the first adsorption holding part.

9. The device has a second lifting mechanism for moving the polymerization substrate vertically on the first adsorption holding section, The processing system according to claim 8, wherein the tip of the separation fall prevention pin is positioned higher than the upper surface of the polymer substrate when the polymer substrate is moved vertically by the second lifting mechanism.

10. The laser irradiation device is, A substrate holding portion for holding the polymerized substrate, A moving mechanism for moving the substrate holding portion between the processing position for processing the polymerized substrate and the transfer position, The system includes a control unit that controls the operation of the detection mechanism, The processing system according to any one of claims 1 to 9, wherein the control unit, after processing the polymerized substrate held in the substrate holding unit, moves the substrate holding unit to the transfer position using the moving mechanism, and then performs control to detect that the second substrate has separated from the first substrate and shifted, and that the second substrate is protruding from the horizontal reference position.

11. The laser irradiation device is, A substrate holding portion for holding the polymerized substrate, A lifting mechanism for moving the polymerized substrate vertically on the substrate holding section, The system includes a control unit that controls the operation of the detection mechanism, The processing system according to any one of claims 1 to 9, wherein the control unit, after processing the polymerized substrate held in the substrate holding unit, moves the polymerized substrate vertically by the lifting mechanism, and then performs control to detect that the second substrate has separated from the first substrate and shifted, and that the second substrate is protruding from the horizontal reference position.

12. The system includes a control unit that controls the operation of the detection mechanism, The processing system according to any one of claims 1 to 9, wherein the control unit, after inserting the transport device into the laser irradiation device, executes control to detect that the second substrate has separated from and shifted relative to the first substrate, and that the second substrate is protruding from the horizontal reference position.

13. The laser irradiation device is, A substrate holding portion for holding the polymerized substrate, A lifting mechanism for moving the polymerized substrate vertically on the substrate holding section, The system includes a control unit that controls the operation of the detection mechanism, The processing system according to any one of claims 1 to 9, wherein the control unit, after transferring the overlapping substrate from the lifting mechanism to the transport device, executes control to detect that the second substrate has separated from and shifted relative to the first substrate, and that the second substrate is protruding from the horizontal reference position.

14. The laser irradiation device is, A substrate holding portion for holding the polymerized substrate, The system includes a control unit that controls the operation of the detection mechanism, The control unit, after the polymerization substrate has been loaded into the laser irradiation device, The processing system according to any one of claims 1 to 9, wherein after transferring the polymerized substrate from the transport device to the substrate holding unit, a detection operation is performed to execute control to detect eccentricity of the polymerized substrate relative to the substrate holding unit.

15. A processing method for processing a polymerized substrate, in which a first substrate and a second substrate are joined together, using a processing system, The processing system is A laser irradiation apparatus for processing the polymerized substrate, The system includes a transport device for transporting the polymerized substrate, The aforementioned processing method is: The polymerized substrate on the substrate holding portion is subjected to laser treatment, A processing method comprising detecting that at least a portion of the polymerized substrate extends beyond a horizontal reference position at a transfer position where the polymerized substrate is transferred between the transport device and the substrate holding unit.

16. The method further includes moving the substrate holding portion between the processing position for performing the laser processing and the transfer position, Detection that the second substrate is separated and misaligned from the first substrate, and that the second substrate is protruding from the horizontal reference position, After moving the substrate holding unit from the processing position to the transfer position, After moving the polymerized substrate vertically on the substrate holding portion, After the transport device is brought into the laser irradiation device, The processing method according to claim 15, which is performed at at least one of the following timings: after the polymerized substrate has been received by the transport device.

17. After the polymerization substrate has been loaded into the laser irradiation device, The processing method according to claim 16, further comprising: performing a detection operation at a timing after transferring the polymerized substrate from the transport device to the substrate holding unit, and detecting that at least a portion of the polymerized substrate, which is eccentric with respect to the substrate holding unit, extends beyond the horizontal reference position.

18. The processing method according to any one of claims 15 to 17, comprising separating the second substrate from the first substrate after laser processing by the laser irradiation device.

19. The aforementioned transport device is A transport arm having a holding surface for the polymerized substrate, The system includes a holding detection mechanism that detects whether at least a portion of the polymerized substrate held by the transport arm is protruding from a horizontal reference position, The processing method according to claim 18, comprising detecting, when transporting the polymerized substrate from the laser irradiation device to the separation device that performs the separation, that the second substrate has separated from the first substrate and shifted, causing the second substrate to protrude from the horizontal reference position.