Substrate processing system, substrate processing method, program, and storage medium

Abstract

This substrate processing system for processing a substrate comprises a laser irradiation device for irradiating the substrate with laser light, and a control device. The control device executes control in the laser irradiation device for irradiating the substrate with the laser light in a plurality of annular shapes having different diameters. An annular irradiation region of the laser light has a light gap between an irradiation start position and an irradiation end position of the laser light, and a circumferential position of the light gap with respect to one radial direction of the substrate is different in the adjacent irradiation region.

Description

Substrate processing system, substrate processing method, program, and storage medium

[0001] The present disclosure relates to a substrate processing system, a substrate processing method, a program, and a storage medium.

[0002] Each of Patent Documents 1 and 2 discloses a laser irradiation device (modification device) having a chuck for holding an overlapping wafer and a laser head for irradiating the overlapping wafer held by the chuck with laser light. In the laser irradiation device (modification device), the overlapping wafer is irradiated with laser light in a circular pattern.

[0003] International Publication No. 2020 / 54504 Japanese Patent Application Laid-Open No. 2021-106197

[0004] The technology according to the present disclosure appropriately controls the irradiation start position and irradiation end position of the laser light in the annular irradiation area when processing a substrate by irradiating the substrate with laser light in an annular irradiation area.

[0005] One aspect of the present disclosure is a substrate processing system for processing a substrate, comprising: a laser irradiation device that irradiates the substrate with laser light; and a control device, wherein the control device controls the laser irradiation device to irradiate the substrate with the laser light in a plurality of circular rings having different diameters, wherein the circular irradiation area of ​​the laser light has an optical gap between an irradiation start position and an irradiation end position of the laser light, and the circumferential position of the optical gap with respect to one radial direction of the substrate is different in adjacent irradiation areas.

[0006] According to the present disclosure, when processing a substrate by irradiating it with laser light in a circular shape, it is possible to appropriately control the irradiation start position and irradiation end position of the laser light in the circular irradiation area.

[0007] 1 is a side view showing a schematic configuration of a laminated wafer to be processed; FIG. 2 is a plan view showing a schematic configuration of a wafer processing system; FIG. 3 is a side view showing a schematic configuration of a laser irradiation device; FIG. 4 is a plan view showing a schematic configuration of a laser irradiation device; FIG. 5 is an explanatory diagram showing how a separation device operates; FIG. 6 is a side view showing a schematic configuration of an inspection device; FIG. 7 is a plan view showing a schematic configuration of an inspection device; FIG. 8 is a flow diagram showing main steps of wafer processing in a wafer processing system; FIG. 9 is an explanatory diagram showing how the inspection device operates; FIG. 10 is an explanatory diagram showing how a laminated wafer is irradiated with laser light; FIG. 11 is an explanatory diagram showing how a laser absorbing layer is irradiated with laser light; FIG. 12 is an explanatory diagram showing how a laser absorbing layer is irradiated with laser light; FIG. 13 is an explanatory diagram showing how a laser absorbing layer is irradiated with laser light in a comparative example; FIG. 14 is an explanatory diagram showing how laser light is branched by a branching element; FIG. 15 is an explanatory diagram showing how a laser absorbing layer is irradiated with laser light in another embodiment; FIG. 16 is a plan view showing a schematic configuration of a laser irradiation device in another embodiment; and FIG. 17 is an explanatory diagram showing an example of a projected image.

[0008] Hereinafter, a wafer processing system as a substrate processing system and a wafer processing method as a substrate processing method according to the present embodiment will be described with reference to the drawings. Note that 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.

[0009] 1 , a wafer processing system 1 according to this embodiment, which will be described later, processes an overlapped wafer T as an overlapped substrate in which a first wafer W as a first substrate and a second wafer S as a second substrate are bonded together. 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.

[0010] The first wafer W is a semiconductor wafer such as a silicon substrate. In this embodiment, the first wafer W has a substantially circular disk shape. A laser absorbing layer P, a device layer Dw, and a surface film Fw are laminated on the surface Wa of the first wafer W in this order from the surface Wa side. The laser absorbing layer P absorbs laser light irradiated from a laser irradiation unit 110, which will be described later. The laser absorbing layer P may be made of, for example, an oxide film (SiO ２ The surface film Fw may be, for example, an oxide film (THOX film, SiO ２ Examples of the surface film Fw include a silicon dioxide film (SiO 2 film, TEOS film), a silicon carbide (SiC film), a silicon carbide (SiCN) film, and an adhesive. The first wafer W is bonded to the second wafer S via this surface film Fw. Note that the device layer Dw and the surface film Fw may not be formed on the surface Wa. In this case, the laser absorption layer P is formed on the second wafer S side, and the device layer Ds on the second wafer S side, which will be described later, is transferred to the first wafer W side.

[0011] The second wafer S is a semiconductor wafer such as a silicon substrate. On the surface Sa of the second wafer S, a device layer Ds and a surface film Fs are laminated in this order from the surface Sa side. 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. Note that the device layer Ds and the surface film Fs may not be formed on the surface Sa.

[0012] 2 , the wafer processing system 1 has a configuration in which a load / unload station 2 and a processing station 3 are integrally connected. In the load / unload station 2, for example, a FOUP F capable of accommodating a plurality of overlapping wafers T, a plurality of first wafers W, or a plurality of second wafers S is loaded and unloaded between the load / unload station 2 and the outside. The processing station 3 is equipped with various processing devices that perform desired processing on the overlapping wafers T, the first wafers W, or the second wafers S.

[0013] The carry-in / out station 2 is provided with a FOUP mounting table 10 on which a plurality of FOUPs F, for example, three FOUPs F, are mounted. A wafer transfer device 20 is provided on the positive X-axis side of the FOUP mounting table 10. The wafer transfer device 20 moves on a transfer path 21 extending in the Y-axis direction, and is configured to be able to transfer the overlapped wafer T, the first wafer W, or the second wafer S between the FOUP F on the FOUP mounting table 10 and a transition stage 30 and an inversion device 31, which will be described later.

[0014] In the carry-in / out station 2, a transition stage 30 and an inversion device 31 are stacked on the X-axis positive side of the wafer transfer device 20. The transition stage 30 temporarily stores the overlapped wafer T, the first wafer W, or the second wafer S for transfer to and from the processing station 3. The inversion device 31 inverts the front and back surfaces of the first wafer W. The number and arrangement of the transition stages 30 and inversion devices 31 are not limited to those in this embodiment and can be determined arbitrarily.

[0015] The processing station 3 is provided with a wafer transfer device 40, an inspection device 50, a laser irradiation device 60, a cleaning device 70, and a separation device 80. The wafer transfer device 40 is disposed on the positive X-axis side of the transition stage 30 and the inversion device 31. The inspection device 50 and the laser irradiation device 60 are disposed on the positive Y-axis side of the wafer transfer device 40, and the cleaning device 70 and the separation device 80 are disposed on the negative Y-axis side of the wafer transfer device 40. The number and arrangement of the inspection devices 50, laser irradiation devices 60, cleaning devices 70, and separation devices 80 are not limited to those in this embodiment and can be determined arbitrarily. For example, the inspection device 50 may be stacked with the transition stage 30 and the inversion device 31.

[0016] The wafer transport device 40 is configured to be freely movable on a transport path 41 extending in the X-axis direction, and is configured to be able to transport the overlapped wafer T, the first wafer W, or the second wafer S to the transition stage 30, the inversion device 31, the inspection device 50, the laser irradiation device 60, the cleaning device 70, and the separation device 80.

[0017] The laser irradiation device 60 applies laser light (e.g., CO ２ The laser irradiation device 60 irradiates a laser beam (laser) to reduce the bonding strength at the interface between the first wafer W and the laser absorption layer P. In the following description, the interface (in this embodiment, the interface between the first wafer W and the laser absorption layer P) whose bonding strength has been reduced by the irradiation of the laser beam may be referred to as a "separation surface." The laser irradiation device 60 has a control device 61, which will be described later.

[0018] 3 and 4 , the laser irradiation device 60 has a chuck 100 as a substrate holder that holds the overlapped wafer T on its upper surface (holding surface). The chuck 100 suction-holds the back surface Sb of the second wafer S with the first wafer W on top and the second wafer S on the bottom. The chuck 100 is provided with lifting pins (not shown) for supporting and elevating the overlapped wafer T from below. The lifting pins are inserted into through-holes (not shown) formed through the chuck 100 and are configured to be freely raised and lowered.

[0019] The chuck 100 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 has a built-in motor, for example, as a drive source. The chuck 100 is configured to be rotatable about a vertical axis via the air bearing 101 by the rotation mechanism 103. The slider table 102 is configured to be movable along a rail 106 extending in the Y-axis direction on a base 105 via a movement mechanism 104 provided on the underside of the slider table 102. The drive source of the movement mechanism 104 is not particularly limited, but a linear motor, for example, is used.

[0020] A laser irradiation unit 110 is provided above the chuck 100. The laser irradiation unit 110 includes a laser head 111, an optical system 112, and a lens 113.

[0021] 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. As described above, 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.

[0022] The optical system 112 may have 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.

[0023] The lens 113 irradiates the laser light onto the overlapped wafer T held by the chuck 100. The laser light emitted from the laser irradiation unit 110 passes through the first wafer W and is irradiated onto the laser absorption layer P. The lens 113 may be configured to be movable in the horizontal direction by a movement mechanism (not shown), or may be configured to be movable up and down in the vertical direction by a lifting mechanism (not shown).

[0024] A detection unit 120 is provided above the chuck 100. The detection unit 120 detects the state of the first wafer W (overlapped wafer T) held by the chuck 100. For example, the detection unit 120 is a laser displacement meter that measures the height of the back surface Wb (top surface) of the first wafer W. The detection unit 120 is configured to be movable in the horizontal direction by a movement mechanism (not shown). The detection unit 120 measures the height of the back surface Wb at multiple points on the first wafer W and detects the state of the back surface Wb. The detection results of the detection unit 120 (measurement results of the height of the back surface Wb) are output to the control device 61 or the control device 90, which will be described later. Note that in this embodiment, the detection unit 120 is moved to detect the state of the entire back surface Wb. However, the detection unit 120 may be fixed, and the chuck 100 may be moved in the horizontal direction and rotated to detect the state of the entire back surface Wb.

[0025] The method for detecting the state of the back surface Wb of the first wafer W in the detection unit 120 is not limited to this embodiment. The detection unit 120 may have any configuration as long as it can detect unevenness on the back surface Wb.

[0026] An imaging unit 130 is provided above the chuck 100 on the positive Y-axis side of the lens 113. The imaging unit 130 includes at least one camera. An image captured by the imaging unit 130 is output to a control device 61 or a control device 90, which will be described later. The laser irradiation device 60 determines the position of the overlapped wafer T on the chuck 100 based on the image obtained by the imaging unit 130, and aligns the overlapped wafer T based on this.

[0027] The separating device 80 separates the first wafer W from the second wafer S (overlapped wafer T) using the interface between the first wafer W and the laser absorption layer P as the separation surface, where the bonding strength has been reduced by the laser irradiation device 60, as the base point.

[0028] 5, the separation device 80 has a suction chuck 200 that suction-holds the back surface Sb of the second wafer S from below, and a suction pad 210 that suction-holds the back surface Wb of the first wafer W from above. In the separation device 80, with the suction chuck 200 suction-holding the second wafer S and the suction pad 210 suction-holding the first wafer W as shown in FIG. 5, the suction pad 210 is raised to separate the first wafer W from the laser absorption layer P.

[0029] The configuration of the separating device 80 is not limited to this, and any configuration may be used as long as it can separate the first wafer W from the second wafer S.

[0030] The cleaning device 70 cleans the first wafer W and the second wafer S separated by the separating device 80. The configuration of the cleaning device 70 is not particularly limited.

[0031] 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 arranged in the wafer processing system 1, but the first cleaning apparatus for cleaning the first wafer W and the second cleaning apparatus for cleaning the second wafer S may also be arranged independently in the wafer processing system 1.

[0032] The inspection device 50 inspects the front surface Wa of the first wafer W separated from the second wafer S, and inspects whether separation has been properly performed at the separation surface. The inspection device 50 has a control device 51, which will be described later.

[0033] 6 and 7 , the inspection device 50 has a casing 300. A chuck 301 that holds the back surface Wb of the first wafer W is provided inside the casing 300. A rail 302 that extends in the X-axis direction is provided on the bottom surface of the casing 300. A driving unit 303 that rotates the chuck 301 and is movable along the rail 302 is provided on the rail 302.

[0034] An imaging unit 310 is provided on a side surface (positive X-axis direction) inside the casing 300. The imaging unit 310 includes, for example, a wide-angle CCD camera. A half mirror 311 is provided near the center of the upper part of the casing 300. The half mirror 311 is provided facing the imaging unit 310, with its mirror surface tilted 45 degrees upward toward the imaging unit 310 from a vertically downward orientation. An illumination unit 312 is provided above the half mirror 311. The half mirror 311 and the illumination unit 312 are fixed to the upper surface inside the casing 300. Light from the illumination unit 312 passes through the half mirror 311 and is emitted downward. Therefore, light reflected by an object below the illumination unit 312 is further reflected by the half mirror 311 and captured by the imaging unit 310. In other words, the imaging unit 310 can capture an image of an object in the area illuminated by the illumination unit 312. The image of the first wafer W captured by the imaging unit 310 is output to the control device 51 or the control device 90, which will be described later.

[0035] 1, the wafer processing system 1 described above is provided with a control device 51, a control device 61, and at least one control device 90. The control device 51 individually controls the operation of the inspection device 50. The control device 61 individually controls the operation of the laser irradiation device 60. The control device 90 controls the entire series of wafer processing in the wafer processing system 1.

[0036] The controllers 51, 61, and 90 each process computer-executable instructions that cause the inspection apparatus 50, the laser irradiation apparatus 60, and the wafer processing system 1 to perform the various steps described in this disclosure. The controllers 51, 61, and 90 can each be configured to control the elements of the inspection apparatus 50, the laser irradiation apparatus 60, and the wafer processing system 1 to perform the various steps described herein. In one embodiment, some or all of the controllers 51 may be included in the inspection apparatus 50, some or all of the controllers 61 may be included in the laser irradiation apparatus 60, and some or all of the controllers 90 may be included in the wafer processing system 1.

[0037] The control devices 51, 61, and 90 may each include a processing unit, a storage unit, and a communication interface. The control devices 51, 61, and 90 may each be realized by, for example, a computer. The processing unit may be configured to read a program providing 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 a medium when needed. The acquired program is stored in the storage unit and read from the storage unit and executed by the processing unit. The medium may be various computer-readable storage media or a communication line connected to the communication interface. The storage medium may be temporary or non-temporary. The processing unit may be a CPU (Central Processing Unit) or one or more circuits. The storage unit may include a RAM (Random Access Memory), a ROM (Read Only Memory), a HDD (Hard Disk Drive), a SSD (Solid State Drive), or a combination thereof. The communication interface may communicate between the inspection device 50, the laser irradiation device 60, and the wafer processing system 1 via a communication line such as a LAN (Local Area Network).

[0038] In this embodiment, the control devices 51 and 61 are installed separately for the inspection device 50 and the laser irradiation device 60, respectively, but the control devices 51 and 61 may be configured integrally with the control device 90. In other words, the operations of the inspection device 50 and the laser irradiation device 60 may be controlled by the control device 90.

[0039] Next, a description will be given of wafer processing performed using the thus configured wafer processing system 1. In this embodiment, the first wafer W and the second wafer S are bonded together in a bonding device (not shown) external to the wafer processing system 1 to form an overlapped wafer T in advance.

[0040] First, a FOUP F containing a plurality of overlapping wafers T is placed on the FOUP placement table 10 of the carry-in / out station 2 .

[0041] Next, the overlapped wafer T is removed from the FOUP F by the wafer transfer device 20 and transferred to the transition stage 30. Subsequently, the overlapped wafer T is transferred to the laser irradiation device 60 by the wafer transfer device 40.

[0042] The overlapped wafer T transferred to the laser irradiation device 60 is first sucked and held by the chuck 100 (St1 in FIG. 8). The chuck 100 sucks and holds the back surface Sb of the second wafer S of the overlapped wafer T.

[0043] Next, the detector 120 is used to detect the condition of the back surface Wb of the first wafer W held by the chuck 100 (St2 in FIG. 8 ). In St2, the detector 120 measures the height of the back surface Wb of the first wafer W, as shown in FIG. 9 . At this time, the height of the back surface Wb is measured at multiple points in the radial direction of the first wafer W, for example, at three points: the center point, the middle point, and the outer periphery point of the first wafer W, and at multiple points in the circumferential direction while the chuck 100 (overlapping wafer T) is rotated by the rotation mechanism 103. The number and positions of the measurement points in the radial direction are arbitrary, and the number and positions of the measurement points in the circumferential direction are also arbitrary. Then, the condition of the back surface Wb of the first wafer W is detected.

[0044] The detection result of the detection unit 120 is output to, for example, the control unit 61. Based on the detection result of the detection unit 120, the control unit 61 determines whether or not to perform laser processing.

[0045] 9 , if a foreign substance E is attached to the holding surface of the chuck 100, a part of the back surface Wb of the first wafer W held by the chuck 100 protrudes, causing unevenness on the back surface Wb. Also, if a foreign substance E is attached to the back surface Sb of the second wafer S before it is held by the chuck 100, unevenness will also occur on the back surface Wb of the first wafer W. Note that the cause of unevenness on the back surface Wb is not limited to the foreign substance E. For example, unevenness on the back surface Wb may occur if there is a burr on the holding surface of the chuck 100 or if the holding surface of the chuck 100 is chipped.

[0046] If unevenness occurs on the back surface Wb of the first wafer W, in the laser processing described below, the laser light is irradiated onto the laser absorbing layer P in the flat portion of the back surface Wb, but defocusing of the laser light occurs in the protruding portion of the back surface Wb, and the focal position of the laser light may be shifted from the laser absorbing layer P. When the focal position of the laser light is shifted from the laser absorbing layer P in this way, it is not possible to reduce the bonding strength of the interface between the first wafer W and the laser absorbing layer P, which becomes the separation surface as described below, and separation may occur at another interface with weak bonding strength, for example, the interface between the laser absorbing layer P and the device layer Dw, during the separation processing in the separation apparatus 80.

[0047] Therefore, when the condition of the back surface Wb of the first wafer W is determined to be abnormal based on the information on the height position of the back surface Wb, i.e., when the unevenness of the back surface Wb is large, the control device 61 determines to stop wafer processing in the wafer processing system 1 (St3 in FIG. 8 ). Specifically, when the height of the protruding portion of the back surface Wb is higher than the height of the surrounding flat portion by a predetermined threshold, for example, 10 μm to 30 μm, the control device 61 stops wafer processing in the wafer processing system 1.

[0048] In St3, the overlapped wafer T whose back surface Wb is determined to be abnormal is returned to the FOUP F or the transition stage 30 without starting processing. Also, the laser processing in the laser irradiation device 60 is stopped, and the state of the chuck 100 is checked. Then, if a foreign substance E is found on the chuck 100, the holding surface of the chuck 100 is cleaned. Also, if the chuck 100 has burrs or defects, the chuck 100 is replaced.

[0049] On the other hand, if the control device 61 determines that the condition of the back surface Wb of the first wafer W is normal based on information on the height position of the back surface Wb, i.e., if there is no or only small unevenness on the back surface Wb, it decides to perform subsequent laser processing on the overlapped wafer T (St4 in Figure 8).

[0050] In St4, as shown in FIG. 10, the laser irradiating unit 110 applies the laser light L(CO ２ The first wafer W is irradiated with pulsed laser light (laser light). At this time, the laser light L passes through the first wafer W from the back surface Wb side of the first wafer W and is absorbed in the laser absorbing layer P. The optical energy of the laser light L absorbed by the laser absorbing layer P is converted into thermal energy. Most of the heat generated in the laser absorbing layer P diffuses toward the first wafer W side, causing the first wafer W to locally expand. The expanded first wafer W has a convex shape, and the laser absorbing layer P is pressed from above (the first wafer W side). As a result, compressive stress is generated in the pressed laser absorbing layer P and tensile stress is generated around the laser absorbing layer P. In this way, the laser light L reduces the bonding strength at the interface between the laser absorbing layer P and the first wafer W. Note that this reduction in bonding strength at the interface between the laser absorbing layer P and the first wafer W is an example of separation of the first wafer W, and other methods may be used for separation. In this embodiment, the phrase "decreased bonding strength" refers to a state in which the bonding strength is reduced at least compared to before irradiation with the laser light L, and includes peeling of the laser absorption layer P and the first wafer W.

[0051] 11 and 12 , the laser absorbing layer P is irradiated with pulsed laser light L while the chuck 100 (superimposed wafer T) is rotated by the rotation mechanism 103. The chuck 100 is then rotated 360° to form a circular irradiation area A of the laser light L. Subsequently, the chuck 100 is moved radially outward by the movement mechanism 104, and then the chuck 100 is further rotated 360° to form a circular irradiation area A of the laser light. The 360° rotation of the chuck 100, the irradiation of the laser light L, and the radially outward movement of the chuck 100 are alternately repeated to form a plurality of circular irradiation areas A of different diameters that are concentric with the laser absorbing layer P from the center to the outer periphery of the laser absorbing layer P. As a result, the entire surface of the laser absorbing layer P is irradiated with the laser light L.

[0052] In addition, in the central region of the laser absorption layer P, it may not be possible to properly maintain the interval between adjacent laser beams L irradiated in the circumferential direction in the annular irradiation region A. In such a case, with the rotation of the chuck 100 stopped, the irradiation position of the laser beam L may be scanned in a ring shape concentric with the laser absorption layer P in a plan view using, for example, a galvanometer mirror (not shown).

[0053] In the following description, the n-th irradiation area A from the innermost (first) to the outer periphery of the plurality of irradiation areas A will be referred to as irradiation area A. ｎ In addition, each irradiation area A ｎ In this case, the position where irradiation of the laser light L starts is designated as the irradiation start position J ｎ The position where the irradiation of the laser light L ends is called the irradiation end position K ｎ In addition, these irradiation start positions J ｎ and irradiation end position K ｎ The area between the light gap G ｎ So, this light gap G ｎ The laser light L is not irradiated onto the

[0054] As a comparative example, for example, as shown in FIG. ｎare formed in one radial direction (Y-axis direction), singular points where the laser light L is not irradiated are densely concentrated in the one radial direction. In this case, a separation surface with reduced bonding strength may not be formed at the interface between the first wafer W and the laser absorption layer P in the one radial direction. In such a case, in the separation process described later, the optical gap G １ ~G ｎ In the region where these are formed side by side, there is a risk that the first wafer W and the laser absorption layer P will not be properly separated in the separation process described below.

[0055] Therefore, in this embodiment, adjacent irradiation areas A ｎ－１ , A ｎ In this case, the optical gap G in one radial direction (Y-axis direction) ｎ－１ , G ｎ The light gap G is arranged so that the circumferential positions of the ｎ－１ , G ｎ That is, the irradiation area A １ , ...A ｎ－１ , A ｎ In this case, the optical gap G １ , ... G ｎ－１ , G ｎ In this case, the singular points where the laser light L is not irradiated can be dispersed in the circumferential direction, and a separation surface with reduced bonding strength can be formed at the interface between the first wafer W and the laser absorption layer P.

[0056] Specifically, the laser beam L is irradiated to a circular irradiation area A ｎ－１ After forming the irradiation area A, the chuck 100 is moved radially outward. ｎ－１ The laser beam L is irradiated to the radially outer side of the circular irradiation area A. ｎ That is, the laser light L is irradiated from the inside to the outside in the radial direction of the laser absorption layer P, and a circular irradiation area A is formed. At this time, the chuck 100 continues to rotate while moving in the radial direction. Then, when the radial movement of the chuck 100 is completed, the position where the laser irradiation unit 110 irradiates the laser light L becomes the irradiation start position J. ｎAs described above, it is preferable to control at least one of the speed of the radial movement of the chuck 100 and the rotation speed of the chuck 100. In this case, the laser processing time can be shortened, and the throughput of wafer processing can be improved.

[0057] As shown in FIG. 12, the irradiation area A １ , ...A ｎ－１ , A ｎ In the figure, adjacent optical gaps G １ , ... G ｎ－１ , G ｎ are preferably arranged at equal intervals (at an interval of distance D1 in the example of FIG. 12). For example, １ , ... G ｎ－１ , G ｎ In order to disperse the circumferential positions of the irradiation start position J １ , ...J ｎ－１ , J ｎ The circumferential position of the light gap G may be changed by a predetermined angle (a predetermined angle other than 360 degrees). ｎ The distance D2 is the irradiation start position J ｎ and irradiation end position K ｎ 11. ｎ－２ , G ｎ－１ , G ｎ 1 is a projection view of the above in the radial direction (X-axis direction).

[0058] Light Gap G ｎ－１ , G ｎ Since stress occurs at the interface between the first wafer W and the laser absorption layer P around ｎ－１ , G ｎ If the distance D1 is secured to a certain extent, the optical gap G ｎ－１ , G ｎ The stress around the optical gap G ｎ－１ , G ｎ This also affects the optical gap G ｎ－１ , G ｎ In this process, stress acts on the interface between the first wafer W and the laser absorption layer P, and a separation surface with reduced bonding strength can be formed.

[0059] In addition, if the irradiation position of the laser light L varies to some extent due to limitations of the device, the irradiation start position J of the laser light L may be ｎ－１，ａ , J ｎ and irradiation end position K ｎ－１ , K. ｎ may be controlled with a margin.

[0060] As described above, the overlapped wafer T is subjected to laser processing in St4, and a separation surface is formed at the interface between the first wafer W and the laser absorption layer P. Then, the overlapped wafer T is transferred by the wafer transfer device 40 to the separation device 80. In the separation device 80, the first wafer W is separated from the second wafer S using the interface between the first wafer W and the laser absorption layer P, whose bonding strength has been reduced by the irradiation of the laser light L, as the separation surface, as shown in FIG. 5 (St5 in FIG. 8).

[0061] 5( a), the suction chuck 200 suction-holds the back surface Sb of the second wafer S, and further the suction pad 210 suction-holds the back surface Wb of the first wafer W. Thereafter, as shown in FIG. 5( b), while the suction pad 210 suction-holds the first wafer W, the suction pad 210 is raised to separate the first wafer W from the laser absorbing layer P. At this time, since the bonding strength at the interface between the laser absorbing layer P and the first wafer W has been reduced by the irradiation of the laser light L as described above, the first wafer W can be separated from the laser absorbing layer P without applying a large load.

[0062] Next, the second wafer S from which the first wafer W has been separated in the separating device 80 is transferred by the wafer transfer device 40 to the cleaning device 70. In the cleaning device 70, the front surface Sa of the second wafer S, which is the surface separated from the first wafer W, specifically the front surface of the laser absorbing layer P, is cleaned (St6 in FIG. 8 ). Note that in the cleaning device 70, the back surface Sb of the second wafer S may also be cleaned in addition to the front 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 Sb of the second wafer S, respectively.

[0063] Next, the second wafer S that has been cleaned by the cleaning device 70 is transported out of the cleaning device 70 by the wafer transport device 40 and transported to the FOUP F on the FOUP mounting table 10 via the transition stage 30 and the wafer transport device 20.

[0064] Meanwhile, the first wafer W separated by the separating device 80 is then transferred to the reversing device 31 by the wafer transfer device 40. This transfer of the first wafer W by the wafer transfer device 40 may be performed simultaneously with or independently from the transfer of the second wafer S. In the reversing device 31, the front and back surfaces of the first wafer W are reversed so that the front surface Wa faces upward (St7 in FIG. 8 ).

[0065] Next, the first wafer W with its front surface Wa facing upward is transferred by the wafer transfer device 40 to the cleaning device 70. In the cleaning device 70, the front surface Wa of the first wafer W, which is the surface separated from the second wafer S, is cleaned (St8 in FIG. 8 ). Note that in the cleaning device 70, the back surface Wb of the first wafer W may also be cleaned in addition to the front surface Wa. Alternatively, separate cleaning units may be provided for cleaning the front surface Wa and the back surface Wb, respectively.

[0066] Next, the first wafer W cleaned by the cleaning device 70 is transferred by the wafer transfer device 40 to the inspection device 50. In the inspection device 50, the front surface Wa of the first wafer W, i.e., the separation surface, is inspected (St9 in FIG. 8).

[0067] In St9, first, the first wafer W is sucked and held by the chuck 301. The back surface Wb of the first wafer W is sucked and held by the chuck 301. Next, the driving unit 303 moves the chuck 301 along the rails 302, while the imaging unit 310 captures an image of the entire front surface Wa of the first wafer W. The image captured by the imaging unit 310 is output to, for example, the control device 51.

[0068] The control device 51 compares the front surface Wa of the first wafer W inspected by the inspection device 50 with the front surface of the reference wafer Wg. The reference wafer Wg is a defect-free, normal first wafer W after wafer processing in the wafer processing system 1. Specifically, the reference wafer Wg is sequentially subjected to the above-described laser processing of the overlapped wafer T (St4), separation processing of the first wafer W (St5), front and back surface inversion of the first wafer W (St6), and cleaning processing of the front surface Wa of the first wafer W (St7). In comparing the front surface Wa of the first wafer W with the front surface of the reference wafer Wg, an image of the front surface Wa of the first wafer W is compared with an image of the front surface of the reference wafer Wg, and a grayscale difference between these images is detected.

[0069] If there is a difference in the grayscale of the images of the first wafer W and the reference wafer Wg, it is determined that the separation state of the front surface Wa of the first wafer W is abnormal. For example, if the first wafer W is not properly separated at the interface between the laser absorption layer P and the laser absorption layer P, the device layer Dw and the surface film Fw remain on the front surface Wa of the first wafer W. The device layer Dw and the surface film Fw have different grayscales from the front surface Wa, which is silicon, and therefore the above-mentioned difference is detected. If it is determined that the front surface Wa of the first wafer W is abnormal, the control device 51 determines to stop wafer processing in the wafer processing system 1 (St10 in FIG. 8 ).

[0070] In St10, the first wafer W whose front surface Wa is determined to be abnormal is collected. Furthermore, wafer processing in the wafer processing system 1 is stopped, and the state of each device is checked. Then, parts within the device are cleaned or replaced.

[0071] On the other hand, if there is no difference in the gray scale of the images of the first wafer W and the reference wafer Wg, or if there is a difference but it is within a predetermined threshold, it is determined that the separation state of the front surface Wa of the first wafer W is normal. In such a case, the first wafer W is carried out of the inspection device 50 by the wafer transfer device 40 and transferred to the FOUP F on the FOUP mounting table 10 via the transition stage 30 and the wafer transfer device 20.

[0072] Thereafter, when the processing of all the overlapped wafers T housed in the FOUP F is completed, the series of wafer processing in the wafer processing system 1 ends.

[0073] According to the above embodiment, in St2, the condition of the backside Wb of the first wafer W held by the chuck 100 is detected using the detection unit 120, so that an abnormality in the chuck 100 or the overlapped wafer T can be detected early. As a result, if it is determined that the condition of the backside Wb is abnormal, wafer processing in the wafer processing system 1 is stopped in St3, so that the yield of product wafers can be improved. Furthermore, in St3, the chuck 100 is cleaned or replaced, so that the yield of product wafers can be further improved.

[0074] Furthermore, if the condition of the back surface Wb of the first wafer W is determined to be normal in St2, laser processing is performed in St4, so that the laser light L can be appropriately irradiated onto the laser absorption layer P, thereby appropriately forming a separation surface at the interface between the first wafer W and the laser absorption layer P.

[0075] In addition, in St4, adjacent circular irradiation areas A ｎ－１ , A ｎ In this case, the optical gap G in one radial direction ｎ－１ , G ｎ Since the circumferential positions of the light gaps G ｎ－１ , G ｎ In St5, stress acts on the interface between the first wafer W and the laser absorption layer P, and a separation surface can be appropriately formed. As a result, in St5, the first wafer W can be appropriately separated from the second wafer S using the separation surface as a base point.

[0076] In St4, the laser light L was irradiated from the radial inside to the radial outside of the laser absorption layer P to form multiple annular irradiation areas A, but the laser light L may also be irradiated from the radial outside to the radial inside.

[0077] Furthermore, in St9, the inspection device 50 inspects the front surface Wa (separated surface) of the first wafer W separated from the second wafer S, thereby enabling early detection of anomalies in the wafer processing. As a result, if it is determined that the front surface Wa is abnormal, the wafer processing in the wafer processing system 1 is stopped in St10, thereby improving the yield of the wafer processing.

[0078] In particular, in St9, the entire surface Wa of the first wafer W is imaged by the imaging unit 310 in the inspection device 50, so that the surface Wa can be inspected in a short time.

[0079] In St9, the front surface Wa (separated surface) of the first wafer W is inspected by the inspection device 50, but the front surface (separated surface) of the laser absorbing layer P of the separated second wafer S may also be inspected. However, the front surface Sa of the separated second wafer S is formed with the laser absorbing layer P, the device layer Dw, the surface film Fw, the surface film Fs, and the device layer Ds, and there is a risk that the inspection device 50 will not be able to properly image the front surface of the laser absorbing layer P. For this reason, inspecting the front surface Wa of the first wafer W as in this embodiment makes it possible to easily and properly image the front surface Wa and properly inspect the state of the front surface Wa.

[0080] In the laser irradiation device 60 of the above embodiment, the laser irradiation unit 110 irradiates the overlapped wafer T with a single-focus laser light L, but the laser light L may be branched and the overlapped wafer T may be irradiated with multi-focus branched laser light.

[0081] First, a configuration capable of emitting branched laser light in the laser irradiation unit 110 will be described. For example, as shown in FIG. 14 , the optical system 112 has a first branching element 114 and a second branching element 115. The branching elements 114 and 115 branch a single laser light L incident from the laser head 111 into multiple laser light L having irradiation points arranged in a linear distribution (on a straight line). The branching elements may have any configuration, and may, for example, be DOEs (Diffractive Optical Elements) or prisms. The number of branches of the laser light L by the branching elements 114 and 115 is not particularly limited, but in this embodiment, the first branching element 114 and the second branching element 115 have different numbers of branches. In the following description, as shown in FIG. 14 , the number of branches of the first branching element 114 is s, and the number of branches of the second branching element 115 is t (where s and t are integers). In the following, each of the branched laser beams L will be referred to as a "branched laser beam L" according to the number of branches. １，１ ~L ｓ，ｔ " Sometimes it is said that

[0082] Each of the branching elements 114 and 115 includes a rotation mechanism (not shown) and is configured to be rotatable about an axis relative to the optical path of the laser light L. This makes it possible to control the arrangement of irradiation points of the multiple laser beams L arranged in a line distribution, in other words, the direction in which the multiple irradiation points on the laser absorption layer P irradiated with the laser light L are arranged.

[0083] In this embodiment, each of the branching elements 114 and 115 includes a moving mechanism (not shown) and is configured to be freely movable in and out of the optical path of the laser light L in the optical system 112. In the optical system 112, by controlling the movement of the first branching element 114 and the second branching element 115 in and out of the optical path, the number of branches of the laser light L output from the laser head 111 and irradiated onto the overlapped wafer T can be arbitrarily controlled.

[0084] In this embodiment, by arranging both the first branching element 114 and the second branching element 115 on the optical path, one laser beam L irradiated from the laser head 111 is divided into s×t branched laser beams L arranged in a substantially rectangular shape. １，１ ~L ｓ，ｔ can branch into

[0085] In addition, by disposing only the first branching element 114 on the optical path and removing the second branching element 115 from the optical path, the single laser beam L irradiated from the laser head 111 is divided into s branched laser beams L arranged in a line distribution. １ ~L ｓ In addition, by disposing only the second branching element 115 on the optical path and removing the first branching element 114 from the optical path, one laser beam L irradiated from the laser head 111 can be branched into t branched laser beams L arranged in a line distribution. １ ~L ｔ Furthermore, by removing both the first branching element 114 and the second branching element 115 from the optical path, the single laser beam L irradiated from the laser head 111 can be irradiated onto the overlapped wafer T as a single laser beam without being branched.

[0086] Next, the laser beam L and the branched laser beam L in the laser irradiation device 60 configured as above ｓ，ｔ In this embodiment, the laser beam L or the branched laser beam L is irradiated from the inside to the outside in the radial direction of the laser absorption layer P in the same manner as in the above embodiment. ｓ，ｔ Irradiate.

[0087] As shown in FIG. 15, in the following description, the laser beam L or the branched laser beam L is directed to the overlapped wafer T. ｓ，ｔ The irradiation conditions will be explained by dividing them into two regions, a central region R1 and a peripheral region R2, set in the laser absorption layer P. The central region R1 is a circular region located at the center of the laser absorption layer P. The peripheral region R2 is an annular region located radially outward from the central region R1. The central region R1 and the peripheral region R2 are configured to irradiate, for example, the laser beam L or the branched laser beam L. ｓ，ｔ The pulse interval and the rotation speed of the chuck 100 are set in advance prior to processing in the laser irradiation device 60 based on various conditions.

[0088] In the central region R1, as in the above embodiment, the laser absorbing layer P is irradiated with pulsed laser light L while the chuck 100 is rotated by the rotation mechanism 103. Then, the 360° rotation of the chuck 100, the irradiation of the laser light L, and the radial outward movement of the chuck 100 are alternately repeated, and a plurality of annular irradiation regions A are formed from the radial inside to the radial outside. １ , A ２ ...are formed in sequence.

[0089] In addition, in the central region R1, the adjacent irradiation regions A １ , A ２ In this case, the optical gap G in one radial direction １ , G ２ The light gap G is arranged so that the circumferential position is different. １ , G ２ That is, the irradiation area A １ , A ２ , ..., the optical gap G １ , G ２ , ... are shifted in the circumferential direction. In this case, the singular points where the laser light L is not irradiated can be dispersed in the circumferential direction, and a separation surface with reduced bonding strength can be formed at the interface between the first wafer W and the laser absorption layer P.

[0090] In the outer peripheral region R2, for example, by arranging both of the branching elements 114 and 115 on the optical path, the laser beam L from the laser head 111 in the laser irradiation unit 110 is divided into a plurality of branched laser beams L, s×t in this embodiment as shown in FIG. １，１ ~L ｓ，ｔ These branched laser beams L １，１ ~L ｓ，ｔ The branched laser beams L are irradiated simultaneously in pulses. １，１ ~L ｓ，ｔ The split laser beam L is irradiated onto the laser absorption layer P at an irradiation point arrangement of a substantially square shape of s×t in plan view (a dotted square frame in FIG. 15). １，１ ~L １，ｔ The arrangement direction of the split laser beams L is arranged along the radial direction of the laser absorption layer P, that is, t split laser beams L are arranged along the radial direction. １，１ ~L １，ｔ is emitted radially.

[0091] In the outer peripheral region R2, the chuck 100 rotates 360° and the laser beam L (branched laser beam L １，１ ~L １，ｔ ) and the chuck 100 is moved radially outward, and a plurality of annular irradiation areas A are formed from the radially inner side to the radially outer side. ｎ－１ , A ｎ At this time, the laser beam L is divided into two beams L １，１ ~L ｓ，ｔ For example, the irradiation area A ｎ represents a plurality of circular branch irradiation regions B ｎ，１ ~B ｎ，ｔ Includes.

[0092] Each branch irradiation area B ｎ，１ ~B ｎ，ｔ are the branched laser beams L １，１ ~L ｓ，ｔ Irradiation start position J ｎ，１ ~J ｎ，ｔ and branched laser light L １，１ ~L ｓ，ｔ Irradiation end position K ｎ，１ ~K ｎ，ｔ These irradiation start positions J ｎ，１ ~J ｎ，ｔ and irradiation end position K ｎ，１ ~K ｎ，ｔ Between each of the split laser beams L １，１ ~L ｓ，ｔ The branched light gap G where the light is not irradiated ｎ，１ ~G ｎ，ｔ In the following description, the branched light gap G ｎ，１ ~G ｎ，ｔ The branched optical gap group H ｎ That is, each irradiation area A ｎ－１ , A ｎ etc. are branched light gap groups H ｎ－１ , H ｎ etc. are included.

[0093] In this embodiment, adjacent irradiation areas A ｎ－１ , A ｎ In this case, the branched light gap group H ｎ－１ , H ｎ The branched light gap group Hｎ－１ , H ｎ That is, the irradiation area A ｎ－２ , A ｎ－１ , A ｎ In the branched light gap group H ｎ－２ , H ｎ－１ , H ｎ Specifically, the branched light gap group H ｎ－２ , H ｎ－１ , H ｎ In order to disperse the circumferential positions of the branched light gap group H ｎ－２ , H ｎ－１ , H ｎ The circumferential position of the branched laser beam L may be changed by a predetermined angle (a predetermined angle other than 360 degrees). １，１ ~L ｓ，ｔ Therefore, singular points where the laser is not irradiated can be dispersed in the circumferential direction, and a separation surface with reduced bonding strength can be formed at the interface between the first wafer W and the laser absorption layer P.

[0094] Furthermore, according to this embodiment, a separation plane is appropriately formed at the interface between the first wafer W and the laser absorption layer P, and the first wafer W can be appropriately separated from the second wafer S using the separation plane as a base point. １，１ ~L ｓ，ｔ Since the laser beam is branched into two and irradiated onto the laser absorption layer P, the processing time can be shortened and the throughput of wafer processing can be improved.

[0095] In the central region R1, the laser beam L is split into branched laser beams L １，１ ~L ｓ，ｔ In the outer peripheral region R2, the number of branches of the laser beam L is not limited to s×t, but can be arbitrarily controlled.

[0096] The laser irradiation device 60 of the above embodiment may have an image acquisition unit 400 as shown in FIG. 16 . The image acquisition unit 400 is provided to the side of the chuck 100, on the negative Y-axis side of the lens 113. The image acquisition unit 400 has a light-projecting unit 401 and a light-receiving unit 402. The light-projecting unit 401 and the light-receiving unit 402 are arranged so that the optical axis M passes through the peripheral portion of the overlapped wafer T. The image acquisition unit 400 irradiates light from the light-projecting unit 401 toward the light-receiving unit 402, and acquires a projection image Q including the peripheral portion of the overlapped wafer T, as shown in FIG. 17 , for example. The projection image Q acquired by the image acquisition unit 400 is output to the control device 61 or the control device 90.

[0097] In such a case, if the state of the back surface Wb of the first wafer W is determined to be normal in St2 described above, the image acquisition unit 400 acquires a projection image Q before performing laser processing using the laser light L in St4. Specifically, the projection image Q is acquired in the circumferential direction while the chuck 100 is rotated by the rotation mechanism 103. The projection image Q acquired by the image acquisition unit 400 is output to, for example, the control device 61.

[0098] 17 from the projected image Q. Because the peripheral edges of the first wafer W and the second wafer S are each chamfered, an unbonded area Ae where the first wafer W and the second wafer S are not bonded exists in the peripheral edge of the overlapped wafer T. In St4, the laser absorbing layer P present in the bonding area Ac is irradiated with the laser light L, and therefore the position of the radial outer end of the laser absorbing layer P, i.e., the irradiation start position of the laser light L, is determined based on the information on the boundary R.

[0099] According to this embodiment, information on the boundary R between the bonded region Ac and the unbonded region Ae of the first wafer W and the second wafer S can be obtained from the projected image Q, and the irradiation start position of the laser light L can be appropriately determined. As a result, it is possible to prevent the laser light L from being irradiated onto the unbonded region Ae on the radially outer side of the laser absorption layer P in St4, thereby suppressing unnecessary consumption of irradiation energy. Furthermore, it is possible to shorten the irradiation time of the laser light L, and improve the throughput of wafer processing.

[0100] In the above-described embodiments, for example, a peeling promoting layer (not shown) may be formed between the laser absorbing layer P and the first wafer W, and the first wafer W may be separated from the second wafer S using the interface between the peeling promoting layer and the laser absorbing layer P as a separation surface. In this case, it is desirable to adopt a peeling promoting layer such that the adhesion force between the peeling promoting layer and the laser absorbing layer P is at least smaller than the adhesion force between the first wafer W and the peeling promoting layer.

[0101] In the above embodiment, 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 first wafer W is separated using the interface between the laser absorption layer P and the first wafer W as the separation surface. However, wafer processing to which the technology of the present disclosure is applied is not limited to this.

[0102] For example, instead of separating the first wafer W at the interface between the first wafer W and the laser absorption layer P, the technology of the present disclosure can also be applied to a case where the first wafer W is separated using 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, etc. as a separation surface.

[0103] For example, the technology of the present disclosure can be applied to a case where a modified surface is formed by irradiating the inside of the first wafer W with laser light L along the surface direction, and the modified surface is used as a base point to separate the back surface Sb side to thin the first wafer W. In other words, the technology of the present disclosure can be applied when a modified surface is formed inside the first wafer W.

[0104] For example, the technology of the present disclosure can be applied to the case of performing so-called edge trimming when removing the peripheral portion of the first wafer W from the second wafer S. In edge trimming, a laser beam is irradiated onto the interface at the peripheral portion of the first wafer W to reduce the bonding strength at the interface, and the technology of the present disclosure can be applied when irradiating this peripheral portion with laser beam. Note that the interface at the peripheral portion of the first wafer W may be the interface between the surface Wa of the first wafer W and another film, or may be an interface within the peripheral portion of the first wafer W.

[0105] 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.

[0106] Furthermore, the effects described in this specification 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.

[0107] REFERENCE SIGNS LIST 1 wafer processing system 60 laser irradiation device 61 control device 90 control device L laser light S second wafer T overlapped wafer W first wafer

Claims

1. A substrate processing system for processing a substrate, comprising: a laser irradiation device that irradiates the substrate with laser light; and a control device, wherein the control device controls the laser irradiation device to irradiate the substrate with the laser light in a plurality of circular rings having different diameters, wherein the circular irradiation area of ​​the laser light has a light gap between an irradiation start position and an irradiation end position of the laser light, and the circumferential position of the light gap with respect to one radial direction of the substrate is different in adjacent irradiation areas.

2. The substrate processing system of claim 1, wherein the control device controls the laser irradiation device to branch the laser light into a plurality of branched laser light beams and irradiate the branched laser light beams in a circular pattern onto the substrate, wherein the circular branched irradiation area of ​​the branched laser light has a branched light gap between an irradiation start position and an irradiation end position of the branched laser light, wherein the plurality of branched irradiation areas included in one irradiation area have a branched light gap group made up of a plurality of the branched light gaps, and wherein the circumferential positions of the branched light gap group relative to one radial direction of the substrate are different in adjacent irradiation areas.

3. The substrate processing system according to claim 2, wherein in the branched irradiation areas, the circumferential position of the branched light gap relative to one radial direction of the substrate is different between adjacent irradiation areas.

4. The substrate processing system of claim 2, wherein the control device performs control in the laser irradiation device to prevent the laser light from branching when irradiating the central region of the substrate with the laser light, and control in the laser irradiation device to branch the laser light into the plurality of branched laser lights when irradiating the peripheral region of the substrate with the laser light.

5. The substrate processing system according to any one of claims 1 to 4, wherein the substrate is a laminated substrate formed by bonding a first substrate and a second substrate, and the substrate processing system comprises: a separation device that separates the first substrate from the laminated substrate using a separation surface formed by the laser irradiation device as a base point; and an inspection device that inspects the separation surface of the first substrate separated by the separation device.

6. The substrate processing system according to claim 5, wherein the inspection device takes an image of the separation surface of the first substrate separated by the separation device and inspects the separation surface.

7. The substrate processing system according to claim 5, further comprising: comparing the inspected separation surface with the separation surface of a reference substrate; and stopping processing of the laminated substrate if an abnormality is found in the inspected separation surface.

8. The substrate processing system according to claim 7, wherein the reference substrate is a first substrate that has been normally irradiated with the laser light and separated from the laminated substrate.

9. A substrate processing method for processing a substrate, comprising: irradiating the substrate with laser light in a plurality of circular rings having different diameters in a laser irradiation device; the circular irradiation areas of the laser light have a light gap between an irradiation start position and an irradiation end position of the laser light; and the circumferential position of the light gap with respect to one radial direction of the substrate is different in adjacent irradiation areas.

10. A substrate processing method as described in claim 9, comprising, in the laser irradiation device, branching the laser light into a plurality of branched laser light beams and irradiating the branched laser light beams in a circular pattern onto the substrate, wherein the circular branched irradiation area of ​​the branched laser light has a branched light gap between an irradiation start position and an irradiation end position of the branched laser light, wherein the plurality of branched irradiation areas included in one irradiation area have a branched light gap group made up of a plurality of the branched light gaps, and the circumferential positions of the branched light gap group relative to one radial direction of the substrate are different in adjacent irradiation areas.

11. The substrate processing method according to claim 10, wherein in the branched irradiation regions, the circumferential position of the branched light gap with respect to one radial direction of the substrate is different between adjacent irradiation regions.

12. A substrate processing method according to claim 10, wherein, in the laser irradiation device, when the laser light is irradiated onto a central region of the substrate, the laser light is not branched, and when the laser light is irradiated onto a peripheral region of the substrate, the laser light is branched into a plurality of branched laser beams.

13. A substrate processing method according to any one of claims 9 to 12, wherein the substrate is a laminated substrate formed by bonding a first substrate and a second substrate, the substrate processing method comprising: in the laser irradiation device, irradiating the laminated substrate with the laser light to form a separation surface; in a separation device, separating the first substrate from the laminated substrate using the separation surface as a base point; and in an inspection device, inspecting the separation surface of the first substrate separated by the separation device.

14. The substrate processing method according to claim 13, further comprising: in the inspection device, imaging the separation surface of the first substrate separated by the separation device, and inspecting the separation surface.

15. The substrate processing method according to claim 13, comprising: comparing the inspected separation surface with the separation surface of a reference substrate; and stopping processing of the laminated substrate if an abnormality is found in the inspected separation surface.

16. The substrate processing method according to claim 15, wherein the reference substrate is a first substrate that has been normally irradiated with the laser light and separated from the laminated substrate.

17. A program running on a computer of a control device that controls a substrate processing system to cause the substrate processing system to execute a substrate processing method for processing a substrate, wherein the substrate processing system comprises a laser irradiation device that irradiates the substrate with laser light, and the substrate processing method includes irradiating the substrate with the laser light in a plurality of circular rings having different diameters in the laser irradiation device, wherein the circular irradiation area of ​​the laser light has a light gap between an irradiation start position and an irradiation end position of the laser light, and the circumferential position of the light gap with respect to one radial direction of the substrate is different in adjacent irradiation areas.

18. The substrate processing method includes, in the laser irradiation device, branching the laser light into a plurality of branched laser light beams and irradiating the branched laser light beams in a circular pattern onto the substrate, wherein the circular branched irradiation area of ​​the branched laser light has a branched light gap between an irradiation start position and an irradiation end position of the branched laser light, wherein the plurality of branched irradiation areas included in one irradiation area have a branched light gap group made up of a plurality of the branched light gaps, and the circumferential position of the branched light gap group relative to one radial direction of the substrate is different in adjacent irradiation areas.

19. A computer-readable storage medium storing a program that runs on a computer of a control device that controls a substrate processing system to cause the substrate processing system to execute a substrate processing method for processing a substrate, wherein the substrate processing system comprises a laser irradiation device that irradiates the substrate with laser light, and the substrate processing method includes irradiating the substrate with the laser light in a plurality of circular rings having different diameters in the laser irradiation device, wherein the circular irradiation area of ​​the laser light has a light gap between an irradiation start position and an irradiation end position of the laser light, and the circumferential position of the light gap with respect to one radial direction of the substrate is different in adjacent irradiation areas.

20. The storage medium of claim 19, wherein the substrate processing method includes branching the laser light into a plurality of branched laser light beams in the laser irradiation device and irradiating the branched laser light beams in a circular pattern onto the substrate, wherein the circular branched irradiation area of ​​the branched laser light has a branched light gap between an irradiation start position and an irradiation end position of the branched laser light, wherein the plurality of branched irradiation areas included in one irradiation area have a branched light gap group made up of a plurality of the branched light gaps, and wherein the circumferential position of the branched light gap group relative to one radial direction of the substrate is different in adjacent irradiation areas.

Images