JP7716714B2 - Semiconductor device manufacturing method and semiconductor substrate processing device - Google Patents

Description

The technology disclosed in this specification relates to a method for manufacturing a semiconductor device and a semiconductor substrate processing device.

Patent Document 1 discloses a method for processing a semiconductor substrate. In this method, an internally modified layer is formed inside the semiconductor substrate by irradiating the semiconductor substrate with a laser that is focused inside the semiconductor substrate. The internally modified layer is formed so that it spreads along the surface of the semiconductor substrate. By forming such an internally modified layer, the semiconductor substrate can be processed. For example, thinner semiconductor substrates can be obtained by dividing the semiconductor substrate along the internally modified layer.

Japanese Patent Application Laid-Open No. 2020-198391

A semiconductor substrate having an internally modified layer such as the one described above can be split along the internally modified layer by applying a force to the semiconductor substrate in a direction that separates the front and back surfaces. However, when splitting the semiconductor substrate, large stresses are applied locally to the edges of the semiconductor substrate. For this reason, with the technology of Patent Document 1, cracks or chips may occur in the semiconductor substrate starting from the edges of the semiconductor substrate, making it impossible to accurately split the semiconductor substrate along the internally modified layer. This specification provides technology that can suppress cracks and chips from occurring in the semiconductor substrate when it is split.

The method for manufacturing a semiconductor device (100) disclosed in this specification includes the steps of: identifying, on the surface (12a) of a semiconductor substrate (12), a plurality of element regions (60) and a peripheral region (64) surrounding a central region (62) in which the plurality of element regions are present; irradiating the semiconductor substrate with a laser (L) using a laser irradiation device (26) to form a central modified layer (72) extending from the surface of the semiconductor substrate in the thickness direction of the semiconductor substrate and along the interfaces of the plurality of element regions; and irradiating the semiconductor substrate with a laser using the laser irradiation device to form a central modified layer (72) on the semiconductor substrate. The method includes the steps of: forming a peripheral modified layer (74) that extends from the surface of the plate in the thickness direction of the semiconductor substrate and extends to the edge of the semiconductor substrate so as to divide the peripheral region into a plurality of microregions (73) having an area smaller than the element region; irradiating the semiconductor substrate with a laser using the laser irradiation device to form an internal modified layer (76, 176) in the central region inside the semiconductor substrate that extends along the surface of the semiconductor substrate; dividing the semiconductor substrate along the internal modified layer; and dividing the semiconductor substrate along the central modified layer.

After extensive research, the inventors discovered that the stress applied to the edge of a semiconductor substrate when it is divided along an internally modified layer is roughly proportional to the surface area of the region including the edge. In other words, when dividing a semiconductor substrate along an internally modified layer, the larger the surface area of the semiconductor substrate, the higher the stress applied to the edge of the semiconductor substrate. In the above manufacturing method, in addition to a centrally modified layer extending along the interface of each element region, a peripherally modified layer is formed that divides the peripheral region into multiple microregions. The peripherally modified layer is formed to extend to the edge of the semiconductor substrate. In other words, multiple microregions with areas smaller than the element regions are formed at the edge of the semiconductor substrate. Therefore, in the process of dividing the semiconductor substrate along the internally modified layer, the stress applied to the edge of the semiconductor substrate is proportional to the surface area of each of the multiple subdivided microregions. In other words, when dividing the semiconductor substrate along the internally modified layer, the stress applied to the edge of the semiconductor substrate is dispersed. Therefore, this manufacturing method can suppress cracks and chips from occurring in the semiconductor substrate. The semiconductor substrate can then be divided along the central modified layer to manufacture semiconductor devices.

The process of forming the central modified layer, the process of forming the peripheral modified layer, and the process of forming the internal modified layer in the central region may be performed in any order.

The processing apparatus disclosed herein comprises a laser irradiation device, a detection device, and a control device. The control device performs the following steps: using the detection device to identify, on the surface of a semiconductor substrate, multiple element regions and a peripheral region surrounding a central region in which the multiple element regions are located; using the laser irradiation device to irradiate the semiconductor substrate with a laser, thereby forming a central modified layer that extends from the surface of the semiconductor substrate in the thickness direction of the semiconductor substrate and along the interfaces of the multiple element regions; using the laser irradiation device to irradiate the semiconductor substrate with a laser, thereby forming a peripheral modified layer that extends from the surface of the semiconductor substrate in the thickness direction of the semiconductor substrate and extends to the edge of the semiconductor substrate so as to partition the peripheral region into multiple microregions each having an area smaller than the element regions; and using the laser irradiation device to irradiate the semiconductor substrate with a laser, thereby forming an internal modified layer within the central region of the semiconductor substrate that extends along the surface of the semiconductor substrate.

In addition to a central modified layer that extends along the interface of each element region, this processing device forms a peripheral modified layer that divides the peripheral region into multiple microregions. The peripheral modified layer is formed to extend to the edge of the semiconductor substrate. That is, multiple microregions with areas smaller than the element regions are formed at the edge of the semiconductor substrate. Therefore, for example, when dividing the semiconductor substrate along the internal modified layer, the stress applied to the edge of the semiconductor substrate is proportional to the surface area of each of the multiple subdivided microregions. In other words, the stress applied to the edge of the semiconductor substrate is dispersed. Therefore, this processing device can suppress cracks and chips from occurring in the semiconductor substrate in processes subsequent to the processing of the semiconductor substrate.

FIG. FIG. 2 is a cross-sectional view taken along line II-II in FIG. FIG. 2 is a block diagram showing the configuration of a processing device. FIG. 4 is an explanatory diagram of a substrate carrying-in step in the first embodiment. FIG. 4 is an explanatory diagram of a central modified layer forming step in Example 1. FIG. 4 is an explanatory diagram of a peripheral modified layer forming step in Example 1. FIG. 4 is an explanatory diagram of a peripheral modified layer forming step in Example 1. FIG. 4 is an explanatory diagram of an internal modified layer forming step according to the first embodiment. 5A to 5C are explanatory diagrams of a substrate dividing step according to the first embodiment. 5A to 5C are explanatory diagrams of a substrate dividing step according to the first embodiment. 5A to 5C are explanatory diagrams of a substrate dividing step according to the first embodiment. FIG. 10 is an explanatory diagram of an internal modified layer forming step according to a second embodiment. 10A to 10C are explanatory diagrams of a substrate dividing step according to the second embodiment. 10A to 10C are explanatory diagrams of a modified example of the substrate dividing step of the first embodiment.

The technical elements disclosed in this specification are listed below. Note that each of the following technical elements is useful independently.

In one example of a method for manufacturing a semiconductor device disclosed herein, the step of forming the peripheral modified layer may include forming the peripheral modified layer so as to partition the entire peripheral region into the microregions.

This configuration allows for better distribution of stress applied to the outer peripheral region during the process of dividing the semiconductor substrate along the internal modification layer.

In one example of a semiconductor device manufacturing method disclosed herein, the step of forming the internal modified layer may include forming the internal modified layer in the central region and the peripheral region.

This configuration allows the entire semiconductor substrate to be divided along the internal modification layer.

In one example of a method for manufacturing a semiconductor device disclosed in this specification, the central modified layer, the peripheral modified layer, and the internal modified layer may be formed so that the central modified layer and the internal modified layer are connected and the peripheral modified layer and the internal modified layer are not connected.

This configuration prevents cracks and fractures from occurring in the semiconductor layer on the side of the peripheral region where the peripheral modified layer is not formed during the process of dividing the semiconductor substrate along the internal modified layer.

In one example of a semiconductor device manufacturing method disclosed herein, the step of forming the internal modified layer does not necessarily require the internal modified layer to be formed in the outer peripheral region.

With this configuration, in the process of dividing the semiconductor substrate along the internal modified layer, it is possible to divide only the central region while leaving the peripheral region intact.

In one example of a semiconductor substrate processing apparatus disclosed herein, the control device may further perform the steps of dividing the semiconductor substrate along the internal modified layer and dividing the semiconductor substrate along the central modified layer.

This configuration allows the semiconductor substrate to be singulated while suppressing cracks and chips from occurring in the semiconductor substrate.

Example 1
1 and 2 show a semiconductor substrate 12 to be processed. The semiconductor substrate 12 has a central region 62 and a peripheral region 64. The central region 62 has a plurality of element regions 60. In the central region 62, the element regions 60 are arranged in a matrix. Although not shown, an element structure is formed in each element region 60. The element structure formed in each element region 60 may be a MOSFET, an IGBT, a diode, or the like. The peripheral region 64 is located around the central region 62. The peripheral region 64 is the region of the semiconductor substrate 12 excluding the central region 62, and is the region from the periphery of the central region 62 to the outer periphery of the semiconductor substrate 12. In addition, an orientation flat 12f is provided on a part of the outer periphery of the semiconductor substrate 12.

As shown in FIG. 2, the semiconductor substrate 12 has a base substrate 14 and an element semiconductor layer 16. The base substrate 14 and element semiconductor layer 16 are made of GaN (gallium nitride). The thickness of the base substrate 14 is not particularly limited, but is, for example, approximately 350 μm. The element structure in each element region 60 is formed in the element semiconductor layer 16. The element semiconductor layer 16 is a semiconductor layer formed by epitaxial growth on the base substrate 14. The thickness of the element semiconductor layer 16 is not particularly limited, but is, for example, approximately 100 μm. The element structure is formed in the element semiconductor layer 16.

Figure 3 shows the configuration of a processing device 20 that processes a semiconductor substrate 12. The processing device 20 forms a modified layer (described below) inside the semiconductor substrate 12 and divides the semiconductor substrate 12 along the formed modified layer. The processing device 20 has a conveying device 22, a stage 24, a laser light source 26, a camera 28, a dividing device 29, and a control device 30.

The transport device 22 transports the semiconductor substrate 12 into the processing device 20. The transport device 22 places the semiconductor substrate 12 transported into the processing device 20 on the stage 24. The stage 24 is a platform on which the semiconductor substrate 12 is placed when it is processed. The laser light source 26 is positioned above the stage 24 and irradiates the semiconductor substrate 12 placed on the stage 24 with a laser. The camera 28 is positioned above the stage 24 and captures an image of the semiconductor substrate 12 placed on the stage 24.

The dividing device 29 divides the semiconductor substrate along specified regions. The operations performed by the dividing device 29 will be described later.

The control device 30 is electrically connected to the conveying device 22, stage 24, laser light source 26, camera 28, and dividing device 29. The control device 30 controls the operation of the conveying device 22, stage 24, laser light source 26, camera 28, and dividing device 29.

Next, a method for manufacturing the semiconductor device of Example 1 will be described. First, the semiconductor substrate 12 shown in Figures 1 and 2 is prepared. That is, a semiconductor substrate 12 having multiple element structures formed in the central region 62 is prepared.

(Substrate loading process)
In the substrate loading step, the control device 30 causes the transfer device 22 to transfer the semiconductor substrate 12 onto the stage 24. As shown in Fig. 4, a wafer chuck 32 that uses, for example, vacuum suction is provided on the upper surface of the stage 24. The transfer device 22 fixes the semiconductor substrate 12 to the stage 24 by placing the surface 12a (the surface on the element semiconductor layer 16 side) of the semiconductor substrate 12 on the wafer chuck 32.

(Area identification process)
Next, the control device 30 performs a region identification process. In the region identification process, the control device 30 captures an image of the semiconductor substrate 12 on the stage 24 using the camera 28, and calculates the fixed position of the semiconductor substrate 12 relative to the stage 24 (i.e., the position and angle on the stage 24) based on feature points of the semiconductor substrate 12 (e.g., the outer shape including the orientation flat 12f). For example, the control device 30 sets an x-y coordinate system based on the detected feature points and calculates the fixed position of the semiconductor substrate 12. Then, the control device 30 identifies the positions of the central region 62 and the peripheral region 64 based on the calculated fixed positions. Furthermore, the control device 30 identifies the position of each element region 60 within the central region 62.

(Central modified layer forming process)
Next, the control device 30 performs a central modified layer forming process. As shown in FIG. 5 , in the central modified layer forming process, the control device 30 irradiates the back surface 12b of the semiconductor substrate 12 with a laser beam L using the laser light source 26. Here, the control device 30 scans the laser beam L so that the focal point S moves along the interface between each element region 60, and also scans the laser beam L so that the focal point S moves from the front surface 12a of the semiconductor substrate 12 along the thickness direction of the semiconductor substrate 12. At the position of the focal point S, the semiconductor substrate 12 is heated and decomposed. As a result, a central modified layer 72 with reduced crystallinity is formed in the area scanned by the focal point S. That is, in the central region 62, the central modified layer 72 is formed, which partitions each element region 60 on the front surface 12a of the semiconductor substrate 12 and extends from the front surface 12a along the interface between each element region 60 in the thickness direction of the semiconductor substrate 12. The thickness (depth) of the central modified layer 72 is not particularly limited, but in this embodiment, a central modified layer 72 with a depth of approximately 70 μm is formed. The central modified layer 72 is made of, for example, a precipitated layer of gallium, etc. The strength of the central modified layer 72 is lower than the strength of the original material (i.e., GaN) of the semiconductor substrate 12.

(Outer peripheral modified layer forming process)
Next, the control device 30 performs a peripheral modified layer forming process. As shown in FIG. 6 , in the peripheral modified layer forming process, similar to the central modified layer forming process, the control device 30 irradiates the back surface 12b of the semiconductor substrate 12 with a laser beam L using the laser light source 26. Here, the control device 30 scans the focal point S on the front surface 12a of the semiconductor substrate 12 to partition the peripheral region 64 into multiple microregions 73, and also scans the laser beam L so that the focal point S moves from the front surface 12a of the semiconductor substrate 12 along the thickness direction of the semiconductor substrate 12. Here, as shown in FIG. 7 , the control device 30 scans the laser beam L in the x and y directions to form multiple microregions 73 partitioned in a lattice pattern on the front surface 12a of the semiconductor substrate 12. The scanning interval in each direction is not particularly limited, but in this embodiment, the scanning interval is approximately 100 μm. The control device 30 scans the laser beam L so that the area of each microregion 73 is smaller than the area of each element region 60. As a result, a peripheral modified layer 74 with reduced crystallinity is formed in the area scanned by the focal point S. That is, the peripheral region 64 is divided into a plurality of minute regions 73 on the surface 12a of the semiconductor substrate 12, and the peripheral modified layer 74 is formed extending from the surface 12a in the thickness direction of the semiconductor substrate 12. As shown in FIG. 7 , the peripheral modified layer 74 extends to the edge of the peripheral region 64 (i.e., the outer peripheral edge of the semiconductor substrate) and is formed so as to divide the entire peripheral region 64 into minute regions 73 on the surface 12a of the semiconductor substrate 12. The thickness direction length (depth) of the peripheral modified layer 74 is not particularly limited, but in this embodiment, the peripheral modified layer 74 is formed to a depth of approximately 60 μm. That is, the depth of the peripheral modified layer 74 is shallower than the depth of the central modified layer 72. The strength of the peripheral modified layer 74 is lower than the strength of the original material (i.e., GaN) of the semiconductor substrate 12.

(Internal modified layer forming process)
Next, the control device 30 performs an internal modified layer forming process. As shown in FIG. 8 , in the internal modified layer forming process, similar to the central modified layer forming process and the like, the control device 30 irradiates the semiconductor substrate 12 with a laser beam L from the back surface 12b side using the laser light source 26. Here, the control device 30 scans the laser beam L so that a focal point S is formed inside the semiconductor substrate 12. The control device 30 then moves the focal point S in a direction along the front surface 12a of the semiconductor substrate 12, thereby forming an internal modified layer 76 inside the semiconductor substrate 12 that spreads along the front surface 12a. More specifically, the control device 30 forms the internal modified layer 76 inside the element semiconductor layer 16. Here, the control device 30 forms the internal modified layer 76 that spreads over both the central region 62 and the peripheral region 64. The position of the internal modified layer 76 in the thickness direction of the semiconductor substrate 12 is not particularly limited, but in this embodiment, the internal modified layer 76 is formed at a depth of approximately 70 μm from the front surface 12a of the semiconductor substrate 12. Therefore, the formed internal modified layer 76 is connected to the central modified layer 72 but is not connected to the peripheral modified layer 74. The strength of the internal modified layer 76 is lower than the strength of the original material (i.e., GaN) of the semiconductor substrate 12.

(Substrate division process)
After the central modified layer 72, the peripheral modified layer 74, and the internal modified layer 76 are formed, the control device 30 performs a substrate dividing process. In the substrate dividing process, the semiconductor substrate 12 is divided along the internal modified layer 76. Specifically, as shown in FIG. 9 , the control device 30 causes the dividing device 29 to place a support plate 36 equipped with a wafer chuck 34 on the back surface 12b of the semiconductor substrate 12. This fixes the front surface 12a and the back surface 12b of the semiconductor substrate 12 to the wafer chucks 32 and 34. Then, a force is applied to the support plate 36 in a direction away from the stage 24 (indicated by the arrow 80). As described above, the strength of the internal modified layer 76 is lower than that of GaN. Therefore, when a force is applied to the support plate 36 in a direction away from the stage 24, a tensile stress is applied to the semiconductor substrate 12 in its thickness direction. As shown in FIG. 10 , the semiconductor substrate 12 is divided along the internal modified layer 76 into semiconductor layers 112a and 112b. At this time, the division of the semiconductor substrate 12 proceeds starting from the outer peripheral edge of the semiconductor substrate 12 along the internal reformed layer 76, such that the semiconductor layer 112b peels off from the semiconductor layer 112a. Therefore, when the semiconductor substrate 12 is divided along the internal reformed layer 76, a large stress is locally applied to the outer peripheral edge of the semiconductor substrate 12 (i.e., the edge of the outer peripheral region 64). However, in this embodiment, the outer peripheral region 64 has an outer peripheral reformed layer 74 formed at its edge, which divides its surface into multiple minute regions 73. Therefore, the stress applied to the edge of the outer peripheral region 64 is dispersed to a magnitude corresponding to the surface area of each of the multiple minute regions 73, thereby suppressing the occurrence of cracks or chips at the outer peripheral edge of the semiconductor substrate 12. The semiconductor layer 112a includes multiple element regions 60 in which element structures are formed.

Next, the control device 30 performs processes such as surface polishing on the semiconductor layer 112a, and then divides the semiconductor layer 112a along the central modified layer 72. Here, the control device 30 uses the dividing device 29 to apply force to the wafer chuck 32 in a direction along the surface of the semiconductor layer 112a (the direction indicated by arrow 82), as shown in FIG. 11 . This applies tensile stress to the semiconductor layer 112a in its planar direction. As described above, the strength of the central modified layer 72 is lower than that of GaN. Therefore, by applying force in the direction indicated by arrow 82, the semiconductor layer 112a is divided along the central modified layer 72. This separates the element regions 60 from one another, allowing multiple semiconductor devices 100 to be obtained. Because the peripheral modified layer 74 is formed on the semiconductor layer 112a, the semiconductor layer 112a can be divided along the peripheral modified layer 74.

The semiconductor layer 112b includes the base substrate 14 and a layer in which a portion of the element semiconductor layer 16 remains. Therefore, the base substrate 14 can be reused by removing the remaining element semiconductor layer 16 by surface polishing or the like.

As described above, in this embodiment, in addition to the central modified layer 72 extending along the interface of each element region 60, a peripheral modified layer 74 is formed to divide the peripheral region 64 into multiple microregions 73. The peripheral modified layer 74 is formed over the entire peripheral region 64 (i.e., extending to the edge of the semiconductor substrate 12). That is, multiple microregions 73 smaller in area than the element region 60 are formed at the edge of the semiconductor substrate 12. Therefore, in the process of dividing the semiconductor substrate along the internal modified layer 76, the stress applied to the edge of the semiconductor substrate 12 is proportional to the surface area of each of the multiple subdivided microregions 73. That is, when dividing the semiconductor substrate 12 along the internal modified layer 76, the stress applied to the edge of the semiconductor substrate 12 is dispersed. Therefore, the manufacturing method of this embodiment can suppress cracks and chips from occurring in the semiconductor substrate 12 when dividing the semiconductor substrate 12 along the internal modified layer 76.

In addition, in this embodiment, the depth of the peripheral modified layer 74 is shallower than the depth of the central modified layer 72, and the peripheral modified layer 74 is formed so as not to be connected to the internal modified layer 76. In other words, the depth of the peripheral modified layer 74 is set to a depth that does not exceed the dividing surface of the semiconductor substrate 12 (the surface along the internal modified layer 76). In other words, the peripheral modified layer 74 does not remain in the semiconductor layer 112b after dividing the semiconductor substrate 12. Therefore, when dividing the semiconductor substrate 12 along the internal modified layer 76, cracks or breaks caused by the peripheral modified layer 74 are suppressed from occurring on the semiconductor layer 112b side.

Example 2
The manufacturing method of Example 2 differs from the manufacturing method of Example 1 in the internal modified layer forming step. In Example 2, as shown in Fig. 12 , the control device 30 forms an internal modified layer 176 in the central region 62, but does not form an internal modified layer 176 in the outer peripheral region 64.

Then, similar to Example 1, a substrate dividing process is performed. The control device 30 causes the dividing device 29 to place a support plate 36 equipped with a wafer chuck 34 on the back surface 12b of the semiconductor substrate 12. Then, a force is applied to the support plate 36 in a direction away from the stage 24 (indicated by arrow 180). In Example 2, the internal reformed layer 176 is not formed in the peripheral region 64. Therefore, in the peripheral region 64, the semiconductor substrate 12 is difficult to divide along its surface. Therefore, in Example 2, the semiconductor substrate 12 is divided along the internal reformed layer 176 in the central region 62, and at the boundary between the central region 62 and the peripheral region 64, the semiconductor substrate 12 is divided along the central reformed layer 72, starting from the end of the internal reformed layer 176. That is, in Example 2, as shown in FIG. 13 , when the semiconductor substrate 12 is divided along the internal reformed layer 176, only the portion 112c in which the device structure is formed is separated from the semiconductor substrate 12 and remains on the stage 24.

Then, as in Example 1, multiple semiconductor devices can be obtained by applying force in the planar direction to the wafer chuck 32.

In the manufacturing method of Example 2, in the process of dividing the semiconductor substrate 12 along the internal modified layer 176, the region where the peripheral modified layer 74 is formed remains on the base substrate 14 side. Because the peripheral modified layer 74 is densely formed in this region, this region can be easily removed by grinding or polishing.

The above describes the embodiments in detail, but these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and variations of the specific examples given above.

In the above-described embodiments, in the substrate transfer process, the semiconductor substrate 12 may be placed on the stage 24 so that the wafer chuck 32 is positioned only on the surface of the central region 62. With this configuration, as shown in FIG. 14, in Example 1, as in Example 2, only the region where the element structure is formed can be separated from the semiconductor substrate 12. Furthermore, in Example 2, only the region where the element structure is formed can be more easily separated from the semiconductor substrate 12.

Furthermore, in the above-described embodiment, the peripheral modified layer 74 does not have to be formed over the entire peripheral region 64. When dividing the semiconductor substrate 12 along the internal modified layer 76, the greatest stress is applied to the edge of the semiconductor substrate 12. Therefore, the peripheral modified layer 74 only needs to be formed over an area that includes at least the outer edge of the peripheral region 64.

Furthermore, in the above-described embodiment, the central modified layer 72 and the internal modified layer 76, 176 do not have to be connected, and the peripheral modified layer 74 and the internal modified layer 76 may be connected. In other words, the depth of the central modified layer 72 and the peripheral modified layer 74 can be set appropriately depending on the type of semiconductor device to be manufactured, etc.

Furthermore, in the above-described embodiment, the dividing device 29 does not have to be controlled by the control device 30. In other words, the processing device 20 does not have to have the dividing device 29, and a separate device having the function of the dividing device 29 may be prepared.

Furthermore, in the above-described embodiment, the minute regions 73 on the surface 12a of the semiconductor substrate 12 have a rectangular shape, but the shape of the minute regions 73 is not particularly limited and may be other polygonal shapes, such as a triangular or hexagonal shape.

(Reference example)
In the above-described embodiment, the central modified layer 72 is formed by irradiating the laser L, but instead of the central modified layer 72, the grooves may be formed by using a dicing blade.

The technical elements described in this specification or drawings exhibit technical utility either alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. Furthermore, the technologies illustrated in this specification or drawings simultaneously achieve multiple objectives, and achieving any one of those objectives is itself technically useful.

12: Semiconductor substrate 20: Processing device 22: Conveyor device 24: Stage 26: Laser light source 28: Camera 29: Dividing device 30: Control device 60: Element region 62: Central region 64: Peripheral region 72: Central modified layer 73: Micro region 74: Peripheral modified layer 76: Internal modified layer

Claims (7)

A manufacturing method for manufacturing a semiconductor device (100), comprising:
A step of identifying a plurality of element regions (60) and a peripheral region (64) around a central region (62) in which the plurality of element regions are present on a surface (12a) of a semiconductor substrate (12);
a step of forming a central modified layer (72) extending from the surface of the semiconductor substrate in a thickness direction of the semiconductor substrate and along the interfaces of the plurality of element regions by irradiating the semiconductor substrate with a laser (L) using a laser irradiation device (26);
a step of forming a peripheral modified layer (74) extending from the surface of the semiconductor substrate in the thickness direction of the semiconductor substrate and extending to the edge of the semiconductor substrate so as to partition the peripheral region into a plurality of microregions (73) having an area smaller than that of the element region by irradiating the semiconductor substrate with a laser using the laser irradiation device;
forming an internal modified layer (76, 176) extending along the surface of the semiconductor substrate in the central region inside the semiconductor substrate by irradiating the semiconductor substrate with a laser using the laser irradiation device;
dividing the semiconductor substrate along the internal modified layer;
dividing the semiconductor substrate along the central modified layer;
A manufacturing method comprising: The manufacturing method described in claim 1, wherein in the step of forming the peripheral modified layer, the peripheral modified layer is formed so as to divide the entire peripheral region into the microregions. The manufacturing method described in claim 1 or 2, wherein the step of forming the internal modified layer forms the internal modified layer (76) in the central region and the outer peripheral region. The manufacturing method described in claim 3, wherein the central modified layer, the peripheral modified layer, and the internal modified layer are formed so that the central modified layer and the internal modified layer are connected and the peripheral modified layer and the internal modified layer are not connected. The manufacturing method described in claim 1 or 2, wherein the step of forming the internal modified layer does not form the internal modified layer (176) in the outer peripheral region. A processing device (20) for processing a semiconductor substrate,
a laser irradiation device (26);
a detection device (28);
A control device (30);
Equipped with
The control device
identifying, on a surface of a semiconductor substrate, a plurality of element regions and a peripheral region surrounding a central region in which the plurality of element regions are present, by the detection device;
forming a central modified layer extending from the surface of the semiconductor substrate in a thickness direction of the semiconductor substrate and along interfaces of the plurality of element regions by irradiating the semiconductor substrate with a laser using a laser irradiation device;
a step of forming a peripheral modified layer extending from the surface of the semiconductor substrate in the thickness direction of the semiconductor substrate and extending to an edge of the semiconductor substrate so as to partition the peripheral region into a plurality of microregions each having an area smaller than that of the element region, by irradiating the semiconductor substrate with a laser using the laser irradiation device;
forming an internal modified layer in the central region inside the semiconductor substrate, the internal modified layer extending along the surface of the semiconductor substrate, by irradiating the semiconductor substrate with a laser beam using the laser irradiation device;
To execute
Processing equipment. The control device
dividing the semiconductor substrate along the internal modified layer;
dividing the semiconductor substrate along the central modified layer;
The processing device according to claim 6 , further comprising: