Processing method and processing system

Abstract

In a polymerized substrate formed by joining a first substrate and a second substrate, an inspection is conducted to determine whether the peripheral edge of the first substrate has been properly removed. [Solution] A method for processing a superimposed substrate in which a first substrate and a second substrate are joined, comprising: removing the peripheral edge of the first substrate; imaging the outer edge of the first substrate after the removal of the peripheral edge using a camera; calculating at least one of the mean or standard deviation of the gray value in a first region corresponding to the peripheral edge from the first image taken after the removal of the peripheral edge; and determining whether the peripheral edge of the first substrate has been properly removed based on the mean or standard deviation of the gray value in the first region.

Description

Technical Field

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

Background Art

[0002] In Patent Document 1, in a polymerized substrate in which a first substrate and a second substrate are joined, a modification layer forming device that forms a modification layer inside the first substrate along the boundary between the peripheral portion and the central portion of the first substrate to be removed, and a peripheral portion removing device that removes the peripheral portion of the first substrate based on the modification layer are disclosed.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The technology according to the present disclosure inspects whether the peripheral portion of the first substrate is appropriately removed in a polymerized substrate in which the first substrate and the second substrate are joined.

Means for Solving the Problems

[0005] One aspect of the present disclosure is a method for processing a polymerized substrate in which a first substrate and a second substrate are joined, including removing the peripheral portion of the first substrate, imaging the outer end portion of the first substrate after removing the peripheral portion using a camera, calculating at least either the average value or the standard deviation of the gray values in a first region corresponding to the peripheral portion from a first captured image after removing the peripheral portion, and determining whether the peripheral portion of the first substrate is appropriately removed based on the average value or the standard deviation of the gray values in the first region.

Effects of the Invention

[0006] According to this disclosure, in a polymerized substrate in which a first substrate and a second substrate are joined, it is possible to inspect whether or not the peripheral edge of the first substrate has been properly removed. [Brief explanation of the drawing]

[0007] [Figure 1] This is a side view showing an example of the configuration of a polymerized wafer to be processed. [Figure 2] This is a plan view showing a schematic configuration of the wafer processing system according to this embodiment. [Figure 3] This is a cross-section showing the unbonded region, peripheral modified layer, and segmented modified layer formed on a polymerized wafer. [Figure 4] This is a plan view showing the schematic configuration of the interface modification device and the internal modification device. [Figure 5] This is a side view showing a schematic configuration of the interface modification device and the internal modification device. [Figure 6] This is an explanatory diagram showing the main processes of wafer processing in a wafer processing system. [Figure 7] This is a flowchart showing the main steps in wafer processing in a wafer processing system. [Figure 8] This is an explanatory diagram showing the main inspection process in an interface modification apparatus. [Figure 9] This is an explanatory diagram showing the main inspection process in an interface modification apparatus. [Figure 10] This is a flowchart showing the main inspection process in an interface modification device. [Figure 11] This is an explanatory diagram showing the inspection process in the internal modification device. [Figure 12] This is an explanatory diagram showing the inspection process in the internal modification device. [Figure 13] This is an explanatory diagram showing the inspection process in the internal modification device. [Figure 14] This is an explanatory diagram showing the inspection process in the internal modification device. [Figure 15] This is an explanatory diagram showing the inspection process in the internal modification device. [Figure 16]It is a flowchart showing the main processes of inspection in an internal modification device. [Figure 17] It is an explanatory diagram showing another formation example of a peripheral modification layer inside the first wafer. [Figure 18] It is an explanatory diagram showing the state of inspection in a peripheral removal device. [Figure 19] It is an explanatory diagram showing the state of inspection in a peripheral removal device. [Figure 20] It is an explanatory diagram showing the state of inspection in a peripheral removal device. [Figure 21] It is an explanatory diagram showing the state of inspection in a peripheral removal device. [Figure 22] It is an explanatory diagram showing the state of inspection in a peripheral removal device. [Figure 23] It is a flowchart showing the main processes of inspection in a peripheral removal device.

Embodiments for Carrying Out the Invention

[0008] In the manufacturing process of a semiconductor device, in a polymerized substrate in which a first substrate (a silicon substrate such as a semiconductor) having devices such as a plurality of electronic circuits formed on its surface and a second substrate are joined, the peripheral portion of the first substrate may be removed, that is, so-called edge trimming may be performed.

[0009] The edge trimming of the first substrate is performed, for example, using the substrate processing system disclosed in Patent Document 1. That is, a modification layer is formed by irradiating a laser beam inside the first substrate, and the peripheral portion is removed from the first substrate using the modification layer as a base point. Further, according to the substrate processing system described in Patent Document 1, a modified surface is formed by irradiating a laser beam on the interface where the first substrate and the second substrate are joined, thereby reducing the bonding force between the first substrate and the second substrate in the peripheral portion and appropriately removing the peripheral portion.

[0010] Incidentally, when forming a modified surface at the interface where the first substrate and the second substrate are joined to reduce the bonding force, various factors such as misalignment of the laser beam axis may prevent the modification from being properly applied to the entire peripheral edge of the material to be removed. Furthermore, if the modification cannot be applied to the entire peripheral edge in this way, for example, if the modification is not applied to a part of the circumferential direction or if the width of the modified surface is not uniform around the entire circumference, a portion of the peripheral edge of the first substrate to be removed may remain on the central side of the first substrate, potentially causing the generation of particles or other issues in subsequent processes.

[0011] The technology described herein has been made in view of the above circumstances, and in a polymerized substrate in which a first substrate and a second substrate are joined, the peripheral edge of the first substrate is appropriately removed. Hereinafter, the wafer processing system as a processing system and the wafer processing method as a processing method according to this embodiment will be described with reference to the drawings. In this specification and drawings, elements having substantially the same functional configuration are denoted by the same reference numerals to avoid redundant explanation.

[0012] In the wafer processing system 1 described later according to this embodiment, processing is performed on a polymerized wafer T, which is a polymerized substrate formed by bonding a first wafer W as a first substrate and a second wafer S as a second substrate, as shown in Figure 1. Hereinafter, in the first wafer W, the side that is bonded to the second wafer S will be called the surface Wa, and the side opposite to surface Wa will be called the back surface Wb. Similarly, in the second wafer S, the side that is bonded to the first wafer W will be called the surface Sa, and the side opposite to surface Sa will be called the back surface Sb.

[0013] The first wafer W is a semiconductor wafer, such as a silicon substrate, and has a device layer Dw formed on its surface Wa side, which includes multiple devices. A bonding film Fw is further formed on the device layer Dw, and the first wafer S is bonded to the first wafer S via this bonding film Fw. Examples of bonding films Fw include oxide films (THOX film, SiO2 film, TEOS film), SiC film, SiCN film, or adhesive. The peripheral edge We of the first wafer W is chamfered, and the cross-section of the peripheral edge We decreases in thickness towards its tip. The peripheral edge We is the part that will be removed in the edge trimming described later, and is, for example, a range of 0.5 mm to 3 mm radially from the outer edge of the first wafer W. In the following description, the region radially inward from the peripheral edge We to be removed on the first wafer W may be referred to as the central portion Wc.

[0014] The second wafer S has a similar configuration to the first wafer W, for example, with a device layer Ds and a bonding film Fs formed on its surface Sa, and its peripheral edge is chamfered. The second wafer S does not necessarily have to be a device wafer with the device layer Ds formed on it; for example, it may be a support wafer that supports the first wafer W. In this case, the second wafer S functions as a protective material that protects the device layer Dw of the first wafer W.

[0015] As shown in Figure 2, the wafer processing system 1 has a configuration in which an loading / unloading station 2 and a processing station 3 are connected as an integrated unit. At the loading / unloading station 2, for example, cassettes C capable of accommodating multiple polymerized wafers T are loaded and unloaded to and from the outside. The processing station 3 is equipped with various processing devices for performing desired processing on the polymerized wafers T.

[0016] The loading / unloading station 2 is equipped with a cassette mounting table 10 on which a cassette C capable of accommodating multiple polymerized wafers T is placed. Adjacent to the cassette mounting table 10, on the positive X-axis side, is a wafer transport device 20. The wafer transport device 20 moves along a transport path 21 extending in the Y-axis direction and is configured to transport polymerized wafers T between the cassette C on the cassette mounting table 10 and the transition device 30 described later.

[0017] At the loading / unloading station 2, a transition device 30 is provided adjacent to the wafer transport device 20 on the positive X-axis side of the wafer transport device 20 for transferring the polymerized wafer T between the loading / unloading station 2 and the processing station 3.

[0018] Processing station 3 is equipped with a wafer transport device 40, an interface modification device 50, an internal modification device 60, a peripheral removal device 70, and a cleaning device 80.

[0019] The wafer transfer device 40 is located on the positive X-axis side of the transition device 30. The wafer transfer device 40 is configured to move freely along a transfer path 41 extending in the X-axis direction and is capable of transporting polymerized wafers T to the transition device 30, interface modification device 50, internal modification device 60, edge removal device 70, and cleaning device 80 of the loading / unloading station 2.

[0020] The interface modification apparatus 50 irradiates the interface between the first wafer W and the second wafer S with laser light (interface laser light, for example, a CO2 laser) to form an unbonded region Ae (see Figure 3) in the peripheral We to be removed, in which the bonding force between the first wafer W and the second wafer S is reduced.

[0021] As shown in Figures 4 and 5, the interface modification apparatus 50 has a chuck 100 that holds the polymerized wafer T on its upper surface. The chuck 100 holds the back surface Sb of the second wafer S by adsorption when the first wafer W is positioned on top and the second wafer S is positioned on the bottom. The chuck 100 is supported by a slider table 102 via an air bearing 101. A rotation mechanism 103 is provided on the lower side of the slider table 102. The rotation mechanism 103 incorporates, for example, a motor as a drive source. The chuck 100 is configured to rotate freely around a vertical axis via the air bearing 101 by the rotation mechanism 103. The slider table 102 is configured to move freely on a rail 106 that extends in the Y-axis direction on a base 105 via a moving mechanism 104 provided on its lower side. The drive source for the moving mechanism 104 is not particularly limited, but for example, a linear motor can be used.

[0022] A laser head 110 is provided above the chuck 100. The laser head 110 has a lens 111. The lens 111 is a cylindrical member provided on the lower surface of the laser head 110 and irradiates the inside of the polymerized wafer T held by the chuck 100, more specifically the interface between the first wafer W and the second wafer S, with interface laser light. This modifies the portion of the polymerized wafer T irradiated with interface laser light, forming an unbonded region Ae in which the bonding force between the first wafer W and the second wafer S is reduced. In the technology of this disclosure, "interface between the first wafer W and the second wafer S" includes the interfaces of the first wafer W, the device layers Dw and Ds, the bonding films Fw and Fs, and the second wafer S, as well as the interiors of each. In other words, as long as the bonding force between the first wafer W and the second wafer S can be reduced, the formation location of the unbonded region Ae is not particularly limited.

[0023] The laser head 110 is supported by a support member 112. The laser head 110 is configured to move up and down along a vertically extending rail 113 by a lifting mechanism 114. The laser head 110 is also configured to move in the Y-axis direction by a moving mechanism 115. The lifting mechanism 114 and the moving mechanism 115 are each supported by a support column 116.

[0024] A macro camera 120 and a micro camera 121 are provided above the chuck 100, on the positive Y-axis side of the laser head 110. For example, the macro camera 120 and the micro camera 121 are integrated, with the macro camera 120 positioned on the positive Y-axis side of the micro camera 121. The macro camera 120 and the micro camera 121 are configured to move up and down by a lifting mechanism 122, and further configured to move in the Y-axis direction by a moving mechanism 123. The moving mechanism 123 is supported by a support column 116.

[0025] The macro camera 120 images the outer edge of the first wafer W (polymerized wafer T). The image captured by the macro camera 120 is used, for example, for the alignment of the first wafer W, as described later. The macro camera 120 is equipped with, for example, a coaxial lens and emits light that is transparent to at least the first wafer W, such as infrared light (IR), and also receives reflected light from the object. For example, the imaging magnification of the macro camera 120 is 2x.

[0026] The microcamera 121 images the unjointed region Ae formed at the interface between the first wafer W and the second wafer S. The image captured by the microcamera 121 is used, for example, to detect whether the unjointed region Ae has been properly formed. The microcamera 121 is equipped with, for example, a coaxial lens and irradiates light that is transparent to at least the first wafer W, such as infrared light (IR light), and also receives reflected light from the object. For example, the imaging magnification of the microcamera 121 is 10x, the field of view is about 1 / 5 that of the macrocamera 120, and the pixel size is about 1 / 5 that of the macrocamera 120.

[0027] In this embodiment, a macro camera 120 and a micro camera 121 are arranged as shown in the figure to image the unjointed region Ae formed at the interface between the first wafer W and the second wafer S. By configuring the system to image the unjointed region Ae with the micro camera 121, which has a high imaging magnification, the unjointed region Ae can be detected with higher accuracy compared to the case where the macro camera 120 is used to image the unjointed region Ae.

[0028] In this embodiment, a macro camera 120 and a micro camera 121 are arranged as shown in the figure, but the macro camera 120 may be omitted if, for example, the outer edge of the first wafer W can be appropriately imaged using the micro camera 121.

[0029] In the illustrated example, the chuck 100 is configured to rotate relative to the laser head 110 and move horizontally using the rotation mechanism 103 and the movement mechanism 104. However, the laser head 110 may be configured to rotate relative to the chuck 100 and move horizontally. Alternatively, both the chuck 100 and the laser head 110 may be configured to rotate relative to each other and move horizontally.

[0030] The internal modification apparatus 60 irradiates the interior of the first wafer W with laser light (internal laser light, for example, a YAG laser) to form a peripheral modification layer M1 that serves as a starting point for peeling off the peripheral We and a segmented modification layer M2 (see Figure 3) that serves as a starting point for fragmenting the peripheral We.

[0031] The configuration of the internal modification apparatus 60 is not particularly limited. In one example, the internal modification apparatus 60 has the same configuration as the interface modification apparatus 50. That is, as shown in Figure 4, the internal modification apparatus 60 includes a chuck 200 that holds the polymerized wafer T on its upper surface, a laser head 210 that irradiates the inside of the first wafer W held in the chuck 200 with internal laser light, and a macro camera 220 and a micro camera 221 that image the polymerized wafer T held in the chuck 200. The laser head 210 is equipped with a lens 211. The laser head 210 is also configured to be movable by a support member 212, a rail 213, a lifting mechanism 214, and a moving mechanism 215. The lifting mechanism 214 and the moving mechanism 215 are each supported by a support column 216. The macro camera 220 and the micro camera 221 are configured to be movable by a lifting mechanism 222 and a moving mechanism 223. The moving mechanism 223 is supported by a support column 216.

[0032] The chuck 200 and the laser head 210 are configured to be able to rotate relative to each other and move horizontally, for example, by a rotating mechanism 203 and a moving mechanism 204. The laser head 210 has a lens 211 for irradiating the inside of the first wafer W held in the chuck 200 with internal laser light.

[0033] The macro camera 220 images the outer edge of the first wafer W (polymerized wafer T). The image captured by the macro camera 220 is used, for example, for the alignment of the first wafer W, as described later. The microcamera 221 images the vicinity of the peripheral edge We of the first wafer W, more specifically, the area from the outer edge of the first wafer W to a point slightly radially inward from the planned formation location of the peripheral modification layer M1 (the outer edge of the central part Wc of the first wafer W that remains on the polymerized wafer T due to edge trimming). The image captured by the microcamera 221 is used, for example, to detect whether or not the peripheral modification layer M1 has been properly formed inside the first wafer W.

[0034] The edge removal device 70 removes the peripheral portion We of the first wafer W, i.e., edge trims, using the peripheral modified layer M1 formed in the internal modification device 60 as a starting point. The edge trimming method can be arbitrarily selected. For example, the edge removal device 70 may insert a blade, for example, that has a wedge shape. Alternatively, an impact may be applied to the peripheral portion We by, for example, spraying an air blow or a water jet towards the peripheral portion We.

[0035] The edge removal device 70 may also use an imaging mechanism 71 (see Figure 20) to image the edge of the polymerized wafer T after the removal of the edge portion We, and detect whether or not the edge portion We has been properly removed from the first wafer W. In this case, for example, a CCD camera may be used as the imaging mechanism 71.

[0036] The cleaning apparatus 80 performs a cleaning process on the first wafer W and the second wafer S after edge trimming by the edge removal apparatus 70, removing particles from these wafers. The cleaning method can be arbitrarily selected.

[0037] The wafer processing system 1 described above is provided with a control device 90. The control device 90 is, for example, a computer and has a program storage unit (not shown). The program storage unit stores a program that controls the processing of the polymerized wafer T in the wafer processing system 1. The program storage unit also stores a program that controls the operation of the various processing devices and transport devices and other drive systems to realize the wafer processing described later in the wafer processing system 1. The above program may have been recorded on a storage medium H that is readable by the computer and installed from the storage medium H to the control device 90. The storage medium H may be temporary or permanent.

[0038] Next, a wafer processing procedure performed using the wafer processing system 1 configured as described above will be explained. In this embodiment, a first wafer W and a second wafer S are bonded together to form a polymerized wafer T in advance.

[0039] First, a cassette C containing multiple polymerized wafers T is placed on the cassette platform 10 of the loading / unloading station 2. Next, the polymerized wafers T in the cassette C are removed by the wafer transport device 20 and transported to the interface modification device 50 via the transition device 30 and the wafer transport device 40.

[0040] In the interface modification apparatus 50, first, the polymerized wafer T held in the chuck 100 is moved to the macro imaging position. The macro imaging position is a position where the macro camera 120 can image the outer edge of the first wafer W. At the macro imaging position, while rotating the chuck 100, the macro camera 120 captures images of the outer edge of the first wafer W in a 360-degree circumferential direction. The captured images are output from the macro camera 120 to the control device 90.

[0041] The control device 90 calculates the eccentricity between the rotation center of the chuck 100 and the center of the first wafer W from the image of the macro camera 120. Furthermore, the control device 90 calculates the amount of movement of the chuck 100 to correct the Y-axis component of the eccentricity based on the calculated amount of movement. Based on this calculated amount of movement, the control device 90 moves the chuck 100 horizontally along the Y-axis.

[0042] Next, the interface laser beam L1 is pulsed from the laser head 110 onto a pre-set irradiation area of ​​the interface laser beam L1, thereby modifying the interface between the first wafer W and the second wafer S (in the illustrated example, the interface between the first wafer W and the bonding film Fw) as shown in Figures 3 and 6(a). In this embodiment, "interface modification" includes, for example, the amorphization of the device layer Dw or bonding film Fw at the irradiation position of the interface laser beam L1, or the delamination of the first wafer W and the second wafer S. Furthermore, the interface between the first wafer W and the second wafer S where the unbonded region Ae is formed is not limited to the illustrated example; as long as the bonding force between the first wafer W and the second wafer S can be reduced, the unbonded region Ae can be formed at any position within the polymerized wafer T.

[0043] The irradiation area of ​​the interface laser light L1 is determined, for example, as an annular region having a desired radial width, with the outer edge of the first wafer W as the reference. The radial width of the irradiation area is set to a width that can appropriately remove the peripheral edge We of the first wafer W to be removed. The position of the reference outer edge of the first wafer W may be predetermined based on the alignment position associated with the Y-axis movement of the chuck 100 described above, or it may be acquired based on the imaging results from the macro camera 120 described above.

[0044] In the interface modification apparatus 50, by modifying the irradiation position of the interface laser light L1 at the interface between the first wafer W and the second wafer S, an unbonded region Ae is formed in which the bonding strength between the first wafer W and the second wafer S is reduced (step St1 in Figure 7). In the edge trimming described later, the peripheral portion We of the first wafer W, which is to be removed, is removed, and the presence of this unbonded region Ae allows for the proper removal of this peripheral portion We.

[0045] When an unbonded region Ae is formed at the interface between the first wafer W and the second wafer S, an inspection is then performed to determine whether the unbonded region Ae has been properly formed at the interface (step St2 in Figure 7). The detailed inspection method in the interface modification apparatus 50 will be described later.

[0046] If it is determined in step St2 that the unbonded region Ae is not properly formed, for example, if the width of the unbonded region Ae is greater than the radial width of the peripheral portion We to be removed, and it is determined that the unbonded region Ae is formed radially inward from the planned position for the peripheral modified layer M1, then after the removal of the peripheral portion We, the first wafer W will be floating relative to the second wafer S, which may cause the generation of particles or the like in subsequent processes. In such cases, the wafer transport device 40 removes the polymerized wafer T from inside the interface modification device 50, and the next polymerized wafer T is brought into the interface modification device 50. The polymerized wafer T removed from the interface modification device 50 is, for example, discarded or recovered.

[0047] On the other hand, in step St2, if, for example, the width of the unbonded region Ae is smaller than the radial width of the peripheral portion We to be removed, and it is determined that the peripheral modified layer M1 has not been formed from the planned formation position to the radially outer position, or if, for example, it is determined that there is a gap in a part of the unbonded region Ae, the peripheral portion We cannot be properly peeled off in the unformed part of the unbonded region Ae, and there is a risk that a part of the peripheral portion We will remain on the polymerized wafer T. In such cases, as shown in Figure 7, the unformed portion of the unbonded region Ae is irradiated again with the interface laser light L1 (step St1). In other words, the unbonded region Ae is reformed on the peripheral We to be removed. The conditions for reforming the unbonded region Ae may be fed back into the conditions for forming the unbonded region Ae (step St1) on the polymerized wafer T that will be processed next by the wafer processing system 1.

[0048] In step St2, if it is determined that an unbonded region Ae has been properly formed across the entire peripheral region We to be removed, the polymerized wafer T is then transported to the internal modification apparatus 60 by the wafer transport apparatus 40.

[0049] In the internal modification apparatus 60, first, the polymerized wafer T held in the chuck 200 is moved to the macro imaging position. The macro imaging position is a position where the macro camera 220 can image the outer edge of the first wafer W. At the macro imaging position, while rotating the chuck 200, the macro camera 220 captures images of the outer edge of the first wafer W in a 360-degree circumferential direction. The captured images are output from the macro camera 220 to the control device 90.

[0050] The control device 90 calculates the eccentricity between the rotation center of the chuck 200 and the center of the first wafer W from the image of the macro camera 220. The control device 90 also calculates the amount of movement of the chuck 200 to correct the Y-axis component of the eccentricity based on the calculated amount of movement. Based on this calculated amount of movement, the control device 90 moves the chuck 200 horizontally along the Y-axis. Furthermore, the control device 90 identifies the position of the radial inner end (hereinafter simply referred to as the "inner end") of the unjoined region Ae formed by the interface modification apparatus 50 from the image of the macro camera 220. The irradiation position of the internal laser beam L2 is determined, for example, slightly radially inward from the inner end of the unjoined region Ae detected by the macro camera 220.

[0051] Next, the internal laser beam L2 is irradiated from the laser head 210 to a predetermined irradiation position for the internal laser beam L2, and as shown in Figures 3 and 6(b), a peripheral modification layer M1 and a segmented modification layer M2 are sequentially formed inside the first wafer W (step St3 in Figure 7). The peripheral modification layer M1 serves as the base point for removing the peripheral portion We in the edge trimming described later. The segmented modification layer M2 serves as the base point for fragmenting the peripheral portion We to be removed. Note that in the drawings used in the following explanation, the illustration of the segmented modification layer M2 may be omitted to avoid complexity in the illustration.

[0052] During the formation of the peripheral modification layer M1, a crack C1 extends from the peripheral modification layer M1 into the first wafer W in the thickness direction of the first wafer W. The upper end of the crack C1 reaches, for example, the surface Wa, as shown in Figure 6(b). In this embodiment, the formation position of the peripheral modification layer M1 is set slightly radially inward from the inner edge of the unjointed region Ae. As a result, the lower end of the crack C1 extends from, for example, the lower end of the peripheral modification layer M1 formed in the lowest stage toward the inner edge of the unjointed region Ae, as shown in Figure 6(b).

[0053] Once the peripheral modification layer M1 and the segmented modification layer M2 are formed inside the first wafer W, an inspection is then performed to determine whether the peripheral modification layer M1 has been properly formed inside the first wafer W and whether the crack C1 has extended (step St4 in Figure 7). The detailed inspection method in the internal modification apparatus 60 will be described later.

[0054] If it is determined in step St4 that the peripheral modified layer M1 (crack C1) is not properly formed, the peripheral We may not be properly peeled off in the unextended portion of the crack C1, and a portion of the peripheral We may remain on the polymerized wafer T. In such cases, the unextended portion of the crack C1 is irradiated with internal laser light L2. This forms a new peripheral modification layer M1 inside the first wafer W, and the crack C1 is extended between the inner end of the unbonded region Ae and the lower end of the peripheral modification layer M1 via the new peripheral modification layer M1. The conditions for forming this new peripheral modification layer M1 may be fed back into the conditions for forming the peripheral modification layer M1 on the polymerized wafer T that will be processed next by the wafer processing system 1 (step St3). Alternatively, in such a case, the wafer transport device 40 removes the polymerized wafer T from inside the internal modification device 60 and loads the next polymerized wafer T into the internal modification device 60. The polymerized wafer T removed from the internal modification device 60 is, for example, discarded or recovered.

[0055] In step St4, the polymerized wafer T, which is determined to have a properly formed peripheral modification layer M1 (crack C1) inside the first wafer W, is then transported to the peripheral removal device 70 by the wafer transport device 40. In the peripheral removal device 70, as shown in Figure 6(c), the peripheral portion We of the first wafer W is removed, i.e., edge trimming is performed (step St5 in Figure 7). At this time, the peripheral portion We is peeled off from the central portion Wc of the first wafer W, using the peripheral modification layer M1 and crack C1 as starting points, and is also completely peeled off from the second wafer S, using the unbonded region Ae as a starting point. At this time, the removed peripheral portion We is also broken down into smaller pieces using the divided modification layer M2 as a starting point.

[0056] In removing the peripheral portion We, a blade B, for example, a wedge shape (see Figure 6(c)), may be inserted into the interface between the first wafer W and the second wafer S that form the polymerized wafer T.

[0057] Once the peripheral portion We of the first wafer W is removed, an inspection is then performed to determine whether the peripheral portion We has been properly removed from the first wafer W (step St6 in Figure 7). The detailed inspection method in the peripheral removal apparatus 70 will be described later.

[0058] If it is determined that the peripheral We has not been properly removed in step St6, that is, if a portion of the peripheral We remains on the polymerized wafer T, this may cause the generation of particles or other issues in subsequent processes. In such cases, as shown in Figure 7, the blade B may be reinserted into the unpeeled portion of the peripheral We (step St5). Alternatively, in such a case, the polymerized wafer T may be removed from inside the edge removal device 70 by the wafer transport device 40, and the polymerized wafer T may be discarded or recovered.

[0059] In step St6, the polymerized wafer T, which is determined to have had its peripheral edge We of the first wafer W properly removed, is then transported to the cleaning device 80 by the wafer transport device 40. In the cleaning device 80, the first wafer W and / or the second wafer S, after the peripheral edge We has been removed, are cleaned (step St7 in Figure 7).

[0060] Subsequently, the polymerized wafer T, after all processing has been completed, is transported via the transition device 30 to the cassette C on the cassette stand 10 by the wafer transport device 20. In this way, the series of wafer processing steps in the wafer processing system 1 are completed.

[0061] In the above embodiment, the unbonded region Ae, which reduces the bonding force between the first wafer W and the second wafer S, and the peripheral modified layer M1, which serves as the starting point for delamination of the peripheral region We, were formed in this order. However, the order of their formation is not particularly limited. That is, the peripheral modified layer M1 may be formed inside the first wafer W in the internal modification apparatus 60, and then the unbonded region Ae may be formed at the interface between the first wafer W and the second wafer S in the interface modification apparatus 50.

[0062] Next, we will explain the inspection method for the unbonded region Ae in the interface modification apparatus 50 described above (step St2 in Figure 7 above).

[0063] To inspect the unjointed region Ae, first, as shown in Figure 8, the chuck 100 is rotated while the microcamera 121 images the unjointed region Ae formed in step St1 in a 360-degree circumferential direction (step St2-1 in Figure 10). The captured image is output from the microcamera 121 to the control device 90. The radial imaging width d1 of the unjointed region Ae by the microcamera 121 is determined to be a width that includes at least the outer edge (edge ​​portion) of the first wafer W to the inner edge of the unjointed region Ae.

[0064] In the captured image, as shown in Figure 9, for example, the area outside the outer edge of the first wafer W (outer region: left side of Figure 9) is dark, while the area inside the inner edge of the unbonded region Ae (inner region: right side of Figure 9) is bright. Furthermore, the area between the outer region and the inner region, which is the formation part of the unbonded region Ae (intermediate region: center of Figure 9), has a brightness approximately midway between the outer and inner regions.

[0065] Upon receiving the output of the captured image, the control device 90 divides the intermediate region, which is the part that forms the unjointed region Ae, from the image of the unjointed region Ae in the circumferential direction of 360 degrees captured by the microcamera 121, into multiple divided regions R (see Figure 9) in at least one of the radial or circumferential directions (both radial and circumferential in the illustrated example) (step St2-2 in Figure 10).

[0066] Next, in each of the multiple divided regions R obtained in step St2-2, statistical values ​​of the gray values, such as the mean and standard deviation (Sigma), are calculated (step St2-3 in Figure 10).

[0067] Next, based on the average value and standard deviation of the gray values ​​calculated in step St2-3, it is detected whether the unbonded region Ae was properly formed in step St1 of Figure 7, that is, whether the unbonded region Ae was properly formed around the entire circumference of the first wafer W, whether the width of the unbonded region Ae was uniform around the entire circumference, etc. (step St2-4 of Figure 10).

[0068] Specifically, if the unbonded region Ae is formed appropriately and with a uniform width around the entire circumference of the first wafer W, the mean and standard deviation of the gray values ​​obtained in each of the multiple divided regions R are expected to be approximately the same.

[0069] Therefore, in this embodiment, if the average value and standard deviation of the gray values ​​calculated in each of the multiple divided regions R fall within a predetermined threshold, it is determined that the unbonded region Ae is properly formed around the entire circumference of the first wafer W. The "threshold" in this embodiment is a value at which it is determined that the peripheral portion We can be properly peeled off, and in one example, it can be empirically determined based on the results of the prior processing of the polymerized wafer T. On the other hand, if a segmented region R is detected where either the mean or standard deviation of the gray values ​​deviates from the threshold, it is determined that an unjointed region Ae has not been properly formed in that segmented region R.

[0070] Specifically, if a segmented region R is detected in which the mean or standard deviation of the gray value deviates from the threshold, it is determined that in the segmented region R which is the singularity, the interface laser beam L1 was not focused at the interface between the first wafer W and the second wafer S due to factors such as the occurrence of missed light, and the unjointed region Ae could not be properly formed. This is because, when an unbonded region Ae is formed at the same height inside the polymerized wafer T, the infrared light from the microcamera 121 is reflected and received at the unbonded region Ae, i.e., at the same height inside the polymerized wafer T. In other words, when infrared light is reflected at the same height, the calculated gray value becomes approximately constant. Therefore, if the unjointed region Ae is not properly formed in a part of the circumferential or radial direction of the first wafer W due to the effects of, for example, the occurrence of stray light, specifically, if the unjointed region Ae is not formed at the same height, the reflection height of the infrared light from the microcamera 121 will change. This will change the average value or standard deviation calculated from the gray value, allowing detection that the unjointed region Ae is not properly formed.

[0071] If it is determined in step St2-4 that the unbonded region Ae is not properly formed, the polymerized wafer T is discarded and recovered, or the unbonded region Ae is reformed, as described above. On the other hand, if it is determined that the unbonded region Ae is properly formed, the series of inspections of the unbonded region Ae is completed, and the polymerized wafer T is removed from the interface modification apparatus 50.

[0072] According to this embodiment, based on the gray value of an image captured by a near-infrared camera, the unbonded region Ae (modified state inside the polymerized wafer T) formed at the interface between the first wafer W and the second wafer S can be non-destructively inspected. In other words, the formation state of the unbonded region Ae can be inspected in advance before removing the peripheral portion We of the first wafer W (edge ​​trimming). As a result, if the unbonded region Ae necessary to reduce the bonding strength between the first wafer W and the second wafer S is not properly formed, it is possible to decide whether to reform the unbonded region Ae or discard / recover the polymerized wafer T in which the unbonded region Ae has been formed, without peeling off the peripheral portion We. As a result, the proportion of discarded wafers generated in the wafer processing system 1 can be reduced, or the throughput can be improved.

[0073] Furthermore, according to this embodiment, the peripheral portion We of the first wafer W in which the unbonded region Ae is formed can be imaged with the microcamera 121, and then the formation state of the unbonded region Ae can be easily inspected by simply comparing at least one of the average value or standard deviation of the gray value calculated by the control device 90 with a predetermined threshold. And because the inspection can be performed simply by comparing the calculated values ​​in this way, it is also easy to automatically control the inspection of the formation state of the unbonded region Ae by the control device 90.

[0074] In the above embodiment, the formation state of the unjointed region Ae was examined by comparing at least one of the mean value or standard deviation of the calculated gray values ​​with a predetermined threshold. However, the comparison targets for these parameters are not limited to predetermined thresholds. For example, instead of setting a threshold for comparison in advance, one could use the parameters of other polymerized wafers T whose peripheral region We was imaged (parameters calculated) before the polymerized wafer T being inspected, when the unbonded region Ae was properly formed and the peripheral region We was properly peeled off, as a comparison target. In other words, the processing results of other polymerized wafers T could be set as a threshold and fed back into the processing conditions of the polymerized wafer T being processed. Alternatively, instead of comparing parameters or predetermined thresholds of other polymerized wafers T, gray values ​​obtained within the same plane of the polymerized wafer T being inspected, i.e., in multiple divided regions R, may be compared with each other.

[0075] However, when comparing gray values ​​within the same plane of the polymerized wafer T in this manner, if the unbonded region Ae is not properly formed across the entire periphery We, that is, if the unbonded region Ae is not similarly formed in all divided regions R, there may be no difference in the comparison results, and the formation state of the unbonded region Ae may not be properly inspected. In light of this, it is desirable to set a threshold value for comparison in advance, as shown in the above embodiment.

[0076] In the above embodiment, inspection was performed by imaging the unbonded region Ae with a microcamera 121 provided inside the interface modification apparatus 50. However, the imaging mechanism for imaging the unbonded region Ae can be any camera that can properly capture the unbonded region Ae. For example, if the macrocamera 120 used to image the outer edge of the first wafer W can be used, the microcamera 121 may be omitted from the configuration of the interface modification apparatus 50. Alternatively, instead of performing the inspection inside the interface modification device 50, the inspection of the unbonded region Ae (step St2) may be performed using an inspection device (not shown) independently provided outside the interface modification device 50.

[0077] Next, we will explain the inspection method for the formation status of the peripheral modified layer M1 and the propagation status of the crack C1 (step St4 in Figure 7 above).

[0078] During inspection of the internal modification device 60, first, as shown in Figure 11, the chuck 200 is rotated while the microcamera 221 images the peripheral modification layer M1 and crack C1 formed in step St3 in a 360-degree circumferential direction (step St4-1 in Figure 16). The captured images are output from the microcamera 221 to the control device 90. The radial imaging width d2 by the microcamera 221 is determined by the width including at least the outer edge of the first wafer W, the peripheral modification layer M1 formed inside the first wafer W, and the crack C1.

[0079] Furthermore, as shown in Figure 12, in the captured image, for example, the area outside the outer edge of the first wafer W (outer region: left side of Figure 12) is dark, and the area inside the formation location of the peripheral modification layer M1 (inner region: right side of Figure 12) is bright. Also, in the area where the unbonded region Ae is formed (intermediate region: adjacent to the outer region in Figure 12), the brightness is approximately intermediate between the outer and inner regions. Moreover, in the area where the peripheral modification layer M1 is formed (adjacent to the inner region in Figure 12), infrared light is reflected by the peripheral modification layer M1 formed at the top of the interior of the first wafer W, resulting in a brightness somewhere between the intermediate and inner regions. Furthermore, in the area where the crack C1 extending between the lower end of the peripheral modification layer M1 and the inner end of the unbonded region Ae is formed (between the area where the peripheral modification layer M1 is formed and the intermediate region in Figure 12), the infrared light irradiated by the coaxial incident method is not reflected towards the micro camera 221, and the area becomes approximately as dark as the outer region. In other words, due to the formation of the peripheral modification layer M1 and crack C1, the image captured by the microcamera 221 will have a dark region (crack C1) between the intermediate region and the inner region, and a region with a brightness somewhere between the intermediate region and the inner region (peripheral modification layer M1), compared to the image captured by the microcamera 121 in step St2-1 described above.

[0080] As shown in Figure 12, the control device 90 acquires a profile of the gray value distribution in a rectangular region Q1 that extends radially across the first wafer W, which is part of the circumferential 360-degree image of the peripheral modified layer M1 and crack C1 captured by the micro camera 221 (step St4-2 in Figure 16). In this gray value distribution, the gray value changes abruptly in the areas where the gray value changes, specifically at the boundary between the outer region and the intermediate region, the boundary between the intermediate region and the crack C1 formation area, the boundary between the crack C1 formation area and the peripheral modified layer M1 formation area, and the boundary between the peripheral modified layer M1 formation area and the inner region.

[0081] Next, the gray value distribution of a rectangular region Q1 obtained in step St4-2 (vertical axis in Figure 12) is differentiated with respect to the radial position of the first wafer W (horizontal axis in Figure 12) (step St4-3 in Figure 16). This allows us to calculate the displacement of the Gray value in the radial direction within one rectangular region Q1 shown in Figure 12, and obtain a profile of the Gray value displacement distribution with peaks at the boundaries of each of the aforementioned regions, as shown in Figure 13.

[0082] Next, based on the displacement distribution of a rectangular region Q1 obtained in step St4-3, the displacement height (EdgeHeight) and displacement width (EdgeWidth) of the rectangular region Q1 shown in Figure 13 are calculated (step St4-4 in Figure 16).

[0083] Furthermore, the gray value distribution profile based on the image captured by the microcamera 221 is acquired over 360 degrees in the circumferential direction of the first wafer W. In other words, as shown in Figure 14, for each of the multiple rectangular regions Q1, Q2, ..., Qn arranged in the circumferential direction of the first wafer W, the mean value and standard deviation of the gray values ​​in the gray value distribution, and the displacement height and displacement width in the displacement distribution are acquired and calculated.

[0084] Next, the mean and standard deviation of the gray values ​​obtained in multiple rectangular regions Q1, Q2, ..., Qn, as well as the displacement height and displacement width of the gray value displacement, are graphed with the circumferential position of the first wafer W (360 degrees) on the horizontal axis, as shown in Figure 15 (steps St4-5 in Figure 16).

[0085] Next, based on the relationship between the displacement height and displacement width of the created gray value displacement amount and the circumferential position of the first wafer W, it is detected in step St3 of Figure 7 whether or not the peripheral modification layer M1 was formed around the entire circumference of the first wafer W, and whether or not the crack C1 was properly extended around the entire circumference (steps St4-6 of Figure 16).

[0086] Specifically, if a peripheral modification layer M1 (crack C1) is appropriately formed around the entire circumference of the first wafer W, the displacement height and displacement width of the gray value displacement obtained in multiple rectangular regions Q1, Q2, ..., Qn are expected to show similar trends. In other words, the displacement height and displacement width of the gray value displacement are expected to remain constant regardless of the circumferential position of the first wafer W.

[0087] Therefore, in this embodiment, if the displacement height and displacement width of the gray value displacement amount fall within a preset threshold (second threshold) around the entire circumference of the first wafer W, it is determined that the peripheral modification layer M1 and crack C1 are appropriately formed around the entire circumference of the first wafer W. On the other hand, if there is a singularity where either the displacement height or the displacement width of the gray value displacement amount deviates from the threshold, it is determined that the peripheral modified layer M1 or crack C1 is not properly formed at the circumferential position corresponding to the singularity.

[0088] Specifically, if a singularity is detected in the displacement height of the gray value displacement amount that deviates from the threshold, it is determined that the peripheral modified layer M1 or crack C1 has not been properly formed. This is because, when the peripheral modification layer M1 is properly formed around the entire circumference of the first wafer W, the reflection position (reflection height) of the infrared light from the microcamera 121 becomes approximately constant. Also, when the crack C1 is properly extended around the entire circumference of the first wafer W, no reflection of infrared light from the microcamera 121 is detected around the entire circumference of the first wafer W. Therefore, for example, if the peripheral modification layer M1 is not properly formed in a part of the circumferential direction, the measured gray value of infrared light changes, the displacement height of the displacement distribution shifts, and it can be detected that the peripheral modification layer M1, which is formed at least at the uppermost layer in the thickness direction of the first wafer W, is not properly formed. Alternatively, for example, if a crack C1 is not properly propagating in a part of the circumferential direction, infrared light reflection is detected in that part of the circumferential direction, and it can be detected that the crack C1 is not properly propagating.

[0089] Specifically, if a singularity is detected in the displacement range of the gray value displacement amount that deviates from the threshold, it is determined that crack C1 has not been properly formed. This is because, if the crack C1 extends appropriately around the entire circumference of the first wafer W, the unreflected width of the infrared light from the microcamera 121 becomes constant. In other words, if the width over which reflected infrared light cannot be detected is constant, the calculated displacement width becomes approximately constant. Therefore, for example, if the displacement range of the gray value changes due to a change in the unreflected range of infrared light, the peak position of the displacement range distribution will shift, and it will be possible to detect that the extension width of crack C1 is not constant, that is, that crack C1 is not extending properly.

[0090] If it is determined in step St4-6 that the peripheral modification layer M1 or crack C1 is not properly formed, the polymerized wafer T is discarded and recovered, or the peripheral modification layer M1 or crack C1 is reformed, as described above. In such cases, the formation conditions for the peripheral modification layer M1 and crack C1 may be feedback-controlled to the processing conditions of the polymerized wafer T to be processed next by the wafer processing system 1. On the other hand, if it is determined that the unbonded region Ae is properly formed, the series of inspections of the peripheral modified layer M1 and crack C1 is completed, and the polymerized wafer T is removed from the internal modification apparatus 60.

[0091] According to this embodiment, the peripheral modification layer M1 and crack C1 formed inside the first wafer W can be non-destructively inspected based on the gray value of an image captured by a near-infrared camera. In other words, the formation state of the peripheral modification layer M1 and crack C1 can be inspected in advance before removing the peripheral portion We of the first wafer W (edge ​​trimming). As a result, if the peripheral modification layer M1 or crack C1, which serves as the starting point for peeling off the peripheral portion We, is not properly formed, it is possible to decide whether to reform the peripheral modification layer M1 or crack C1, or to discard or recover the polymerized wafer T, without peeling off the peripheral portion We. As a result, the proportion of discarded wafers generated in the wafer processing system 1 can be reduced, or the throughput can be improved.

[0092] In this embodiment, the peripheral modification layer M1 and crack C1 were inspected in step St4 to determine whether they were properly formed. However, as described above, for peripheral modification layers M1 formed in multiple layers in the thickness direction of the first wafer W, detection by infrared light is not possible for peripheral modification layers M1 formed in any layer other than the uppermost layer in that thickness direction. In light of these points, in step St4, the inspection of the peripheral modified layer M1 may be omitted, and only the extent of crack C1's propagation may be inspected.

[0093] Furthermore, in the above embodiment, the formation position of the peripheral modified layer M1 was set slightly radially inward from the inner end of the unjointed region Ae to form a crack C1 extending diagonally upward from the inner end of the unjointed region Ae. However, as shown in Figure 17, the peripheral modified layer M1 may also be formed at a radial position corresponding to the inner end of the unjointed region Ae. In such a case, since the crack C1 does not extend diagonally upward into the interior of the first wafer W, the above-described step St4, i.e., the inspection of the peripheral modified layer M1 and the crack C1, may be omitted.

[0094] In the above embodiment, inspection was performed by imaging the peripheral modified layer M1 and crack C1 with a microcamera 221 installed inside the internal modification device 60. However, the imaging mechanism for imaging the peripheral modified layer M1 and crack C1 may be a macrocamera 220. In such a case, the microcamera 221 may be omitted from the configuration of the internal modification device 60. Alternatively, instead of performing the inspection inside the internal modification device 60, the peripheral modified layer M1 and cracks C1 may be inspected using an inspection device (not shown) independently provided outside the internal modification device 60. In this case, the inspection device that inspects the peripheral modified layer M1 and cracks C1 may further inspect the unjointed region Ae as described above.

[0095] Next, we will explain the inspection method for the removal status of peripheral We (step St6 in Figure 7 above).

[0096] During inspection in the edge trimming apparatus 70, first, as shown in Figure 18, the outer edge of the first wafer W before the removal of the peripheral portion We is imaged in a 360-degree circumferential direction by the imaging mechanism 71 (e.g., a CCD camera) while rotating a chuck (not shown) (step St6-0 in Figure 23). In other words, in the edge trimming apparatus 70, imaging of the first wafer W is performed prior to step St5 (edge ​​trimming) shown in Figure 7. The captured image is output to the control device 90. The radial imaging width d3 by the imaging mechanism 71 is determined to be a width that includes at least the outer edge (edge ​​portion) of the first wafer W to the inner edge (formation position of the peripheral modified layer M1) of the peripheral portion We to be removed.

[0097] In step St6-0, the imaging mechanism 71 images the back surface Wb of the first wafer W before the removal of the peripheral portion We. In the captured image, as shown in Figure 19, the area outside the outer edge of the first wafer W is darker, and the area inside the outer edge of the first wafer W is brighter.

[0098] Next, a blade B, for example, a wedge shape, is inserted into the interface between the first wafer W and the second wafer S on which the polymerized wafer T is formed (see Figure 6(c)) to remove the peripheral portion We, i.e., perform edge trimming (step St5 in Figures 7 and 23).

[0099] Once the peripheral edge We of the first wafer W is removed, the imaging mechanism 71 (e.g., a CCD camera) is used to image the outer edge of the first wafer W after the removal of the peripheral edge We in a 360-degree circumferential direction, while rotating a chuck (not shown) as shown in Figure 20 (step St6-1 in Figure 23). The captured image is output to the control device 90. It is desirable that the radial imaging width by the imaging mechanism 71 in step St6-1 be the same as the imaging width d3 before the removal of the peripheral portion We in step St6-0.

[0100] Furthermore, as shown in Figure 21, the captured image shows that the area outside the outer edge of the first wafer W (outer region: left side of Figure 21) is darker, while the area radially inward from the outer edge of the first wafer W after the removal of the peripheral We, i.e., the peeled surface of the peripheral We (inner region: right side of Figure 21), is brighter. In addition, the exposed surface of the second wafer S (bonding film Fw in the illustrated example) (intermediate region), which is exposed after the removal of the peripheral We, has a brightness approximately midway between the outer and inner regions. Moreover, the inclined portion corresponding to the formation location of the crack C1 (between the inner region and the intermediate region) is approximately as dark as the outer region.

[0101] Next, the control device 90 calculates statistical values ​​of the grayscale in the annular region (see annular regions Z1 and Z2 in Figure 22) corresponding to the peripheral edge We, from the images of the outer edge of the first wafer W taken in the circumferential direction of 360 degrees in step St6-0 and step St6-1, respectively, such as the mean and standard deviation (Sigma) (step St6-2 in Figure 23).

[0102] Next, based on the average value and standard deviation of the gray values ​​calculated in step St6-2, it is detected whether the peripheral portion We was properly removed from the first wafer W during edge trimming in step St5 (step St6-3 in Figure 23). Specifically, the difference in gray values ​​of the outer edge (annular region Z1 and annular region Z2) of the first wafer W before and after the removal of the peripheral region We obtained in step St6-2 is calculated.

[0103] If the peripheral region We is properly removed around the entire circumference of the first wafer W, it is considered that the gray value of the annular region Z2 obtained from the imaging results after the removal of the peripheral region We is different from the gray value of the annular region Z1 obtained from the imaging results before the removal of the peripheral region We.

[0104] Therefore, in this embodiment, if a change in the gray value is detected in the annular region Z1 and the annular region Z2 around the entire circumference of the first wafer W, it is determined that the peripheral portion We has been appropriately removed around the entire circumference of the first wafer W. On the other hand, if, for example, no change in the gray value occurs in a part of the circumferential direction of the first wafer W, it is determined that the peripheral portion We has not been properly removed in the portion where the gray value remains unchanged.

[0105] If it is determined in step St6-3 that the peripheral portion We has not been properly removed, the blade B is reinserted into the remaining portion of the peripheral portion We as described above. Alternatively, the polymerized wafer T is removed from inside the peripheral removal device 70 and discarded or recovered. On the other hand, if it is determined that the peripheral portion We has been properly removed, the series of inspections of the removal status of the peripheral portion We is completed and the polymerized wafer T is removed from the peripheral removal device 70.

[0106] According to this embodiment, based on the gray value of the image captured by the imaging mechanism 71, it is possible to automatically check whether the peripheral portion We has been properly removed from the first wafer W, without requiring operator judgment. As a result, the throughput of the wafer processing system 1 can be improved.

[0107] In the above embodiment, the presence or absence of the peripheral portion We was checked by comparing the gray values ​​obtained from images taken inside the peripheral removal device 70 before and after edge trimming, but the inspection method is not limited to this. Specifically, instead of comparing the gray value obtained from the image after edge trimming with the gray value obtained from the image before edge trimming, it is possible to check whether the peripheral portion We has been properly removed by comparing it with a threshold value (third threshold) that has been acquired and set in advance when the peripheral portion We has been properly removed, in other words, a threshold value set based on the edge trimming results of other polymerized wafers T. In this case, imaging of the outer edge of the first wafer W before edge trimming in the peripheral removal apparatus 70 (step St6-0 in Figure 23) can be omitted as appropriate.

[0108] In the above embodiment, the inspection was performed inside the peripheral removal device 70, but the inspection may also be performed using an inspection device (not shown) independently provided outside the peripheral removal device 70. In such a case, the inspection device that inspects the removal status of the peripheral portion We may further perform the inspection of the unjointed region Ae and / or the inspection of the peripheral modified layer M1 and crack C1.

[0109] The embodiments disclosed herein should be considered in all respects to be illustrative and not restrictive. The above embodiments may be omitted, replaced, or modified in various ways without departing from the scope and spirit of the appended claims. [Explanation of Symbols]

[0110] 1. Wafer Processing System 50 Interface Modification Device 60 Internal Modification Device 70. Edge removal device 90 Control device 121 Micro Camera Ae Unbonded area L1 Interface Laser Light M1 Peripheral Modified Layer S Second wafer T Polymerized wafer W First wafer We Peripheral area

Claims

1. A method for processing a polymerized substrate in which a first substrate and a second substrate are joined, Removing the peripheral edge of the first substrate, The outer edge of the first substrate after the removal of the peripheral portion is imaged using a camera, From the first captured image after the removal of the peripheral portion, calculate at least one of the mean or standard deviation of the gray value in the first region corresponding to the peripheral portion. This includes determining whether the peripheral portion of the first substrate has been properly removed based on the mean value or standard deviation of the gray values ​​in the first region, Processing method.

2. The outer end of the first substrate before the removal of the peripheral edge is imaged using a camera, From the second image captured before the removal of the peripheral portion, calculate at least one of the mean or standard deviation of the gray value in the second region corresponding to the peripheral portion in a plan view of the first substrate. Calculate the difference between the gray value of the first region and the gray value of the second region, The processing method according to claim 1, further comprising determining whether the peripheral edge of the first substrate has been properly removed based on the difference.

3. The camera is used to capture an image of the outer edge of the entire circumference of the first substrate before the removal of the peripheral edge, This includes taking an image of the outer edge of the entire circumference of the first substrate after the removal of the peripheral edge using the camera, Determining whether the peripheral edge of the first substrate has been properly removed is: If the change in the gray value between the second region and the first region, which is the difference, is detected around the entire circumference of the first substrate, then it is determined that the peripheral edge of the first substrate has been properly removed. The processing method according to claim 2, further comprising determining that the peripheral edge of the first substrate has not been properly removed if the change in the gray value does not occur in a part of the circumferential direction of the first substrate.

4. If it is determined that the peripheral edge of the first substrate has not been properly removed, The processing method according to claim 3, further comprising repeating the removal of the peripheral edge of the first substrate.

5. If it is determined that the peripheral edge of the first substrate has not been properly removed, The processing method according to claim 4, further comprising determining that the peripheral edge has not been properly removed in the unpeeled portion identified as the circumferential portion of the first substrate corresponding to the portion of the gray value in which the change has not occurred.

6. Removing the peripheral portion of the first substrate includes inserting a blade into the interface between the first substrate and the second substrate. The processing method according to claim 5, wherein the repeated removal includes inserting the blade into the interface of the unpeeled portion of the peripheral edge of the first substrate.

7. The processing method according to claim 1, further comprising determining whether the peripheral edge of the first substrate has been properly removed by comparing the mean value or standard deviation of the gray value in the first region with a threshold value set in advance based on the processing result when the peripheral edge of another first substrate having another polymerization substrate has been properly removed.

8. A processing system for processing a polymerized substrate in which a first substrate and a second substrate are joined together, A peripheral edge removal device for removing the peripheral edge of the first substrate, A camera for imaging the outer edge of the first substrate, A control device is provided, The control device is The outer end of the first substrate after the removal of the peripheral edge is imaged using the camera, From the first captured image after the removal of the peripheral portion, calculate at least one of the mean or standard deviation of the gray value in the first region corresponding to the peripheral portion. A processing system that performs control including determining whether the peripheral portion of the first substrate has been properly removed based on the mean value or standard deviation of the gray values ​​of the first region.

9. The control device is The outer end of the first substrate before the removal of the peripheral edge is imaged using the camera, From the second image captured before the removal of the peripheral portion, calculate at least one of the mean or standard deviation of the gray value in the second region corresponding to the peripheral portion in a plan view of the first substrate. Calculate the difference between the gray value of the first region and the gray value of the second region, The processing system according to claim 8, which performs control including determining whether the peripheral edge of the first substrate has been properly removed based on the difference.

10. The control device is The camera is used to capture an image of the outer edge of the entire circumference of the first substrate before the removal of the peripheral edge, The control is performed which includes taking an image of the outer edge of the entire circumference of the first substrate after the removal of the peripheral edge using the camera, Determining whether the peripheral edge of the first substrate has been properly removed is: If the change in the gray value between the second region and the first region, which is the difference, is detected around the entire circumference of the first substrate, then it is determined that the peripheral edge of the first substrate has been properly removed. The processing system according to claim 9, further comprising determining that the peripheral edge of the first substrate has not been properly removed if the change in the gray value does not occur in a part of the circumferential direction of the first substrate.

11. The control device is If it is determined that the peripheral edge of the first substrate has not been properly removed, The processing system according to claim 10, which includes performing control that again removes the peripheral portion of the first substrate.

12. The control device is If it is determined that the peripheral edge of the first substrate has not been properly removed, The processing system according to claim 11, which includes performing control to determine that the peripheral edge has not been properly removed in the unpeeled portion identified as the circumferential portion of the first substrate corresponding to the portion of the gray value in which the change has not occurred.

13. Removing the peripheral portion of the first substrate includes inserting a blade into the interface between the first substrate and the second substrate. The processing system according to claim 12, wherein the repeated removal includes inserting the blade into the interface of the unpeeled portion of the peripheral edge of the first substrate.

14. The control device is The processing system according to claim 8, which includes performing control to determine whether the peripheral portion of the first substrate has been properly removed by comparing the mean value or standard deviation of the gray value of the first region with a threshold value set in advance based on the processing result when the peripheral portion of another first substrate having another polymerization substrate has been properly removed.

Images