WO2019239801A1

WO2019239801A1 - Substrate processing system, and substrate processing method

Info

Publication number: WO2019239801A1
Application number: PCT/JP2019/019883
Authority: WO
Inventors: 隼斗田之上
Original assignee: 東京エレクトロン株式会社
Priority date: 2018-06-12
Filing date: 2019-05-20
Publication date: 2019-12-19

Abstract

A substrate processing system comprising: a thickness-reducing device that reduces the thickness of a substrate to be processed; a segmenting device that segments the reduced-thickness substrate to be processed into a plurality of chips; an etching device that etches the reduced-thickness surface of the chip and the segmented surface of the chip; a gettering-layer-formation device that forms a gettering layer on the surface of the chip that has been reduced in thickness and etched, or in the interior of the chip at a prescribed depth from the surface of the chip that has been reduced in thickness and etched; a conveying device that conveys the substrate to be processed to the thickness-reducing device, the segmenting device, the etching device, and the gettering-layer-formation device; and a control device that controls the thickness-reducing device, the segmenting device, the etching device, the gettering-layer-forming device, and the conveying device.

Description

Substrate processing system and substrate processing method

The present disclosure relates to a substrate processing system and a substrate processing method.

The semiconductor device manufacturing method of Patent Document 1 includes a thinning process, a back surface polishing process, a heavy metal capture layer forming process, and a dicing process in this order. In the thinning step, a part of the silicon substrate having a semiconductor element formed on the front surface is removed from the back surface side, so that the thickness of the silicon substrate is 100 μm or less. In the back surface polishing step, the back surface of the thinned silicon substrate is polished. In the heavy metal capturing layer forming step, a heavy metal capturing layer is formed by irradiating a part or the entire surface of the back surface side of the silicon substrate with laser light. In the dicing process, the silicon substrate is divided into chips.

Japanese Unexamined Patent Publication No. 2011-3576

One embodiment of the present disclosure provides a technique capable of improving the bending strength of the chip and the cleanliness of the chip, and reducing the defective characteristics of the chip.

A substrate processing system according to an aspect of the present disclosure includes:
A thinning device for thinning the substrate to be processed;
A dividing device for dividing the thinned substrate to be processed into a plurality of chips;
An etching apparatus for etching both the thinned surface of the chip and the divided surface of the chip;
A gettering layer forming apparatus for forming a gettering layer in the chip at a predetermined depth from the thinned and etched surface of the chip or from the surface;
A transport device that transports the substrate to be processed to the thinning device, the dividing device, the etching device, and the gettering layer forming device;
A control device that controls the thinning device, the dividing device, the etching device, the gettering layer forming device, and the transfer device.

According to one aspect of the present disclosure, the bending strength of the chip and the cleanliness of the chip can be improved, and the defective characteristics of the chip can be reduced.

FIG. 1 is a plan view showing a substrate processing system according to an embodiment. FIG. 2 is a flowchart illustrating a substrate processing method according to an embodiment. FIG. 3 is a side view showing an outer peripheral portion processing apparatus according to an embodiment. FIG. 4 is a plan view showing a substrate to be processed that has been processed by the outer peripheral portion processing apparatus according to the embodiment. FIG. 5 is a side view showing a state during the processing of the primary processing unit of the thinning device according to the embodiment. FIG. 6 is a side view showing a dividing apparatus according to an embodiment. FIG. 7 is a side view showing an etching apparatus according to an embodiment. FIG. 8 is a side view showing a gettering layer forming apparatus according to an embodiment. FIG. 9 is a plan view showing a gettering layer forming apparatus according to an embodiment. FIG. 10 is a plan view showing a state when a gettering layer is formed on a part of a substrate to be processed according to an embodiment. FIG. 11 is a plan view showing a state when a gettering layer is formed on another part of the substrate to be processed according to the embodiment. FIG. 12 is a plan view illustrating an example of control of the scanning mechanism. FIG. 13 is a plan view showing another example of control of the scanning mechanism. FIG. 14 is a diagram illustrating a state when a gettering layer is formed on a substrate to be processed according to a modification. FIG. 15 is a plan view showing a substrate processing system according to a modification. FIG. 16 is a side view showing an example of the laser processing apparatus shown in FIG. FIG. 17 is a side view showing an example of the dividing apparatus for thinning shown in FIG.

Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the drawings, the same or corresponding components are denoted by the same or corresponding reference numerals, and description thereof may be omitted.

FIG. 1 is a plan view showing a substrate processing system according to an embodiment. In FIG. 1, the X-axis direction, the Y-axis direction, and the Z-axis direction are directions perpendicular to each other, the X-axis direction and the Y-axis direction are horizontal directions, and the Z-axis direction is a vertical direction. The rotation direction with the vertical axis as the center of rotation is also called the θ direction. In this specification, “lower” means vertically downward, and “upper” means vertically upward.

The substrate processing system 1 includes a loading / unloading station 100 for loading and unloading cassettes 101 to 103 for storing the substrate to be processed 10 and a processing station 200 for processing the substrate to be processed 10. The loading / unloading station 100 and the processing station 200 are arranged in this order from the X-axis direction negative side to the X-axis direction positive side.

The loading / unloading station 100 includes a cassette table 110, a transfer area 120, and a substrate table 130. The cassette table 110, the transfer region 120, and the substrate table 130 are arranged in this order from the X axis direction negative side to the X axis direction positive side.

The cassette stand 110 includes a plurality of (for example, three) placement plates 111 to 113. The plurality of mounting plates 111 to 113 are arranged in a line at intervals in the Y-axis direction.

The cassette 101 is placed on the placement plate 111. The cassette 101 accommodates the substrate 10 to be processed before processing. The substrate 10 to be processed is a semiconductor substrate such as a silicon wafer, and has a first main surface 11 and a second main surface 12 facing each other as shown in FIG.

As shown in FIG. 4, the first main surface 11 of the substrate to be processed 10 is partitioned into a plurality of chip regions 13 by a plurality of streets formed in a lattice shape. Devices such as elements, circuits, and terminals are formed in advance in each of the plurality of chip regions 13.

A planned dividing line 14 is set on a street that divides a plurality of chip areas 13. The planned dividing line 14 is a planned line that divides the substrate 10 to be processed into a plurality of chips 40 (see FIG. 9). The chip area 13 is an area where the chip 40 is obtained.

The first main surface 11 of the substrate to be processed 10 is joined to the support substrate 20 via the adhesive 22 and covered with the support substrate 20 as shown in FIG. The substrate to be processed 10, the adhesive 22, and the support substrate 20 constitute a superposed substrate 30.

The support substrate 20 supports the substrate to be processed 10 during the processing of the substrate 10 to be processed by the processing station 200 and suppresses damage to the substrate to be processed 10. The thickness of the support substrate 20 is thicker than the thickness of the processed substrate 10 that has been reduced in thickness. Further, the outer diameter of the support substrate 20 is larger than the outer diameter of the substrate 10 to be processed. The outer diameter of the support substrate 20 may be the same as the outer diameter of the substrate 10 to be processed.

As the support substrate 20, for example, a glass substrate or a semiconductor substrate is used. The following problems that occur when a resin tape is bonded to the first main surface 11 of the substrate to be processed 10 instead of the glass substrate or the semiconductor substrate can be solved. Since the resin tape is thin and soft, when the substrate 10 to be processed is divided into a plurality of chips 40, there is a possibility that the resin tape may be divided together with the substrate 10 to be processed. Further, the protective tape is easily damaged when the substrate to be processed 10 is etched, and there is a possibility that the plurality of chips 40 cannot be held at intervals after the etching of the substrate 10 to be processed. According to this embodiment, since a glass substrate or a semiconductor substrate is used, the above problem can be solved.

The cassette 102 is placed on the placement plate 112. The cassette 102 stores non-defective products among the processed substrates 10 after processing. The non-defective product is divided into a plurality of chips 40, and the plurality of chips 40 are supported by the support substrate 20.

The cassette 103 is placed on the placement plate 113. The cassette 103 accommodates defective products among the processed substrates 10 after processing. The defective product may be one in which processing is interrupted in the middle. For example, the defective product may not be divided into a plurality of chips 40.

The transport area 120 is arranged on the positive side in the X-axis direction of the cassette table 110. A guide rail 121 extending in the Y-axis direction is installed in the transport region 120, and the transport device 122 moves along the guide rail 121.

The transfer device 122 includes a transfer arm 123 that holds the substrate 10 to be processed. The transfer arm 123 is movable not only in the Y axis direction but also in the X axis direction, the Z axis direction, and the θ direction. The transfer arm 123 may be turned upside down to turn the substrate 10 to be turned upside down.

The transfer arm 123 is formed in a fork shape that is divided into two forks so as to be easily inserted into each of the plurality of

cassettes

101, 102, and 103. The transfer arm 123 transfers the substrate 10 to be processed before processing from the cassette table 110 to the substrate table 130. The transfer arm 123 transfers the processed substrate 10 after processing from the substrate table 130 to the cassette table 110.

The transfer device 122 may have a plurality of transfer arms 123 to improve transfer efficiency. For example, while one transfer arm 123 places the substrate 10 to be processed on the substrate stage 130, another transfer arm 123 can receive the processed substrate 10 after the process from the substrate stage 130.

The substrate stand 130 temporarily mounts the substrate to be processed 10 before processing and the substrate to be processed 10 after processing. The substrate table 130 is disposed between the transfer area 120 and the processing station 200. The substrate table 130 is disposed on the positive side in the X-axis direction of the transfer region 120 and is disposed on the negative side in the X-axis direction of the processing station 200.

The processing station 200 includes, for example, an outer peripheral portion processing device 210, a thinning device 220, a cleaning device 230, a dividing device 240, an etching device 250, and a gettering layer forming device 260.

As will be described in detail later, the outer peripheral portion processing apparatus 210 performs processing on the outer peripheral portion of the substrate to be processed 10 as shown in FIG. 3 to stop the extension of cracks from the outer periphery of the substrate to be processed 10 toward the radially inner side. As a result, as will be described in detail later, when the substrate 10 to be processed is thinned, the extension of the crack from the outer periphery of the substrate to be processed 10 to the inside in the radial direction can be stopped, and damage to the chip region 13 can be suppressed.

As will be described in detail later, the thinning device 220 thins the substrate 10 to be processed by grinding the second main surface 12 of the substrate 10 to be processed as shown in FIG. Thereby, the chip 40 can be thinned. The thin plate device 220 is a grinding device for grinding the second main surface 12 of the substrate 10 to be processed. A first defect layer 51 is formed on the second main surface 12 of the substrate 10 to be processed, for example, by contact with the rotating grindstone 224.

As will be described in detail later, the cleaning apparatus 230 cleans the substrate 10 to be processed after the substrate 10 is thinned and before the substrate 10 is divided. Thereby, grinding scraps generated by thinning the substrate to be processed 10 can be washed away from the substrate 10 to be processed.

As will be described in detail later, the dividing device 240 divides the thinned substrate 10 into a plurality of chips 40 as shown in FIG. The plurality of chips 40 are partitioned by, for example, lattice-shaped through grooves 18 (see FIG. 9). The first main surface 41 of the chip 40 is the first main surface 11 of the substrate 10 to be processed. The second main surface 42 of the chip 40 is the second main surface 12 of the substrate 10 to be processed, and is a surface on which the first defect layer 51 is formed when the plate is thinned. The end surface 43 of the chip 40 is a side wall surface of the through groove 18 and is a surface on which the second defect layer 52 is formed at the time of division.

Etching apparatus 250 etches both second main surface 42 of chip 40 and end face 43 of chip 40 as shown in FIG. Since the first defect layer 51 formed on the second main surface 42 and the second defect layer 52 formed on the end face 43 can be removed by etching, the bending strength of the chip 40 can be improved. Here, the bending strength is the maximum stress that acts on the chip 40 before the chip 40 breaks in the bending test. In addition, since the debris 53 attached to the second main surface 42 can be removed by etching, the cleanliness of the chip 40 can be improved. The debris 53 is generated at the time of division.

The gettering layer forming apparatus 260 forms the gettering layer 55 on the second main surface 42 of the chip 40 as shown in FIG. The gettering layer 55 captures impurities such as heavy metals. Unlike the first defect layer 51 (see FIG. 6) removed by the etching apparatus 250, the gettering layer 55 can capture impurities without substantially reducing the bending strength of the chip 40.

Note that the gettering layer forming apparatus 260 may form the gettering layer 55 inside the chip 40 at a predetermined depth from the second main surface 42 of the chip 40. In this case as well, impurities can be captured without substantially reducing the bending strength of the chip 40.

Further, the processing station 200 includes a transfer device 280 as shown in FIG. The transfer device 280 transfers the substrate 10 to be processed to the outer peripheral portion processing device 210, the thinning device 220, the cleaning device 230, the dividing device 240, the etching device 250, and the gettering layer forming device 260. The transfer device 280 may transfer the substrate 10 to be processed by transferring the superposed substrate 30. The substrate 10 to be processed can be reinforced by the support substrate 20 during transport, and damage to the substrate 10 being transported can be reduced. The transport device 280 includes, for example, a first transport unit 281 and a second transport unit 282.

The first transport unit 281 moves in the X-axis direction along the guide rail 284 installed in the transport region 283. The first transfer unit 281 includes a transfer arm 285 that holds the substrate 10 to be processed. The first transport unit 281 may include a plurality of transport arms 285 for improving transport efficiency.

The transfer arm 285 may be formed in a fork shape that is divided into two forks, similarly to the transfer arm 123, for cost reduction. The transfer arm 285 sucks the target substrate 10 with the first main surface 11 of the target substrate 10 facing down. The transfer arm 285 is movable not only in the X axis direction but also in the Y axis direction, the Z axis direction, and the θ direction.

On the negative side in the X-axis direction of the transfer area 283, the substrate table 130 of the carry-in / out station 100 is arranged. On the other hand, an outer peripheral portion processing apparatus 210 is disposed on the positive side in the X-axis direction of the transport region 283. In addition, a dividing device 240 and a gettering layer forming device 260 are arranged on the Y axis direction positive side of the transport region 283. On the other hand, a cleaning device 230 and an etching device 250 are arranged on the Y axis direction negative side of the transfer region 283.

The first transport unit 281 transports the substrate 10 to be processed to various apparatuses adjacent to the transport region 283. The first transport unit 281 transports the substrate 10 to be processed from the substrate table 130 to the outer peripheral processing apparatus 210. In addition, the first transport unit 281 is supplied from the cleaning device 230 to the dividing device 240, from the dividing device 240 to the etching device 250, from the etching device 250 to the gettering layer forming device 260, and from the gettering layer forming device 260 to the substrate table 130. Each of the substrates to be processed 10 is transported.

Incidentally, as will be described in detail later, the thinning device 220 is disposed on the X axis direction positive side of the outer peripheral portion processing apparatus 210 and is disposed on the opposite side of the conveyance region 283 across the outer peripheral portion processing apparatus 210. Therefore, in addition to the 1st conveyance part 281 which moves in the conveyance area | region 283, the 2nd conveyance part 282 is provided.

Around the second transport unit 282, an outer peripheral processing device 210, a thinning device 220, and a cleaning device 230 are arranged. The second transport unit 282 transports the substrate 10 to be processed from the outer peripheral processing device 210 to the thinning device 220. The second transport unit 282 transports the substrate 10 to be processed from the thinning device 220 to the cleaning device 230.

The second transport unit 282 is not particularly limited, but is an articulated robot having a plurality of arms (see FIG. 1). The articulated robot has a suction pad that sucks the substrate 10 to be processed at the tip. The suction surface of the suction pad is directed downward. The suction pad sucks the target substrate 10 from above with the first main surface 11 of the target substrate 10 facing downward. The suction pad has a circular suction surface having a diameter larger than the diameter of the substrate to be processed 10 and sucks the substrate to be processed 10 on the suction surface. The suction pad is movable in the X axis direction, the Y axis direction, the Z axis direction, and the θ direction.

In addition, although the conveying apparatus 280 has the 1st conveying part 281 and the 2nd conveying part 282 in this embodiment, you may have only the 1st conveying part 281. In the latter case, the thinning device 220 is provided adjacent to the transport area 283.

In the processing station 200, the arrangement and number of the outer peripheral portion processing apparatus 210, the thinning apparatus 220, the cleaning apparatus 230, the dividing apparatus 240, the etching apparatus 250, and the gettering layer forming apparatus 260 can be arbitrarily selected.

The substrate processing system 1 includes a control device 300. The control device 300 is configured by a computer, for example, and includes a CPU (Central Processing Unit) 301 and a storage medium 302 such as a memory. The storage medium 302 stores a program for controlling various processes executed in the substrate processing system 1. The control device 300 controls the operation of the substrate processing system 1 by causing the CPU 301 to execute a program stored in the storage medium 302. In addition, the control device 300 includes an input interface 303 and an output interface 304. The control device 300 receives a signal from the outside through the input interface 303 and transmits a signal to the outside through the output interface 304.

Such a program may be stored in a computer-readable storage medium and may be installed in the storage medium 302 of the control device 300 from the storage medium. Examples of the computer-readable storage medium include a hard disk (HD), a flexible disk (FD), a compact disk (CD), a magnetic optical desk (MO), and a memory card. The program may be downloaded from a server via the Internet and installed in the storage medium 302 of the control device 300.

FIG. 2 is a flowchart showing a substrate processing method according to an embodiment. A plurality of steps shown in FIG. 2 are performed under the control of the control device 300. In the plurality of steps shown in FIG. 2, when the transfer device 122 of the loading / unloading station 100 takes out the substrate 10 to be processed from the cassette 101 placed on the cassette stand 110 and places the taken out substrate 10 on the substrate stand 130. To be started. In addition, the order of the several process shown in FIG. 2 is not specifically limited. Moreover, some processes shown in FIG. 2 may not be performed.

The substrate processing method includes a step S101 in which the transfer device 280 receives the substrate 10 to be processed from the loading / unloading station 100 and loads it into the processing station 200. A device is formed in advance on the first main surface 11 of the substrate 10 to be processed.

The substrate processing method includes a step S102 in which the outer peripheral processing apparatus 210 performs processing on the outer peripheral portion of the substrate to be processed 10 to stop extension of a crack from the outer periphery of the target substrate 10 toward the radially inner side. As a result, as will be described in detail later, when the substrate 10 to be processed is thinned, the extension of the crack from the outer periphery of the substrate to be processed 10 to the inside in the radial direction can be stopped, and damage to the chip region 13 can be suppressed.

The substrate processing method includes a step S103 in which the thin plate apparatus 220 thins the substrate to be processed 10 by grinding the second main surface 12 of the substrate 10 to be processed. Thereby, the chip 40 can be thinned. A first defect layer 51 is formed on the second main surface 12 of the substrate 10 to be processed, for example, by contact with the rotating grindstone 224.

The substrate processing method includes a step S104 in which the cleaning apparatus 230 cleans the target substrate 10 after the target substrate 10 is thinned and before the target substrate 10 is divided. Thereby, grinding scraps generated by thinning the substrate to be processed 10 can be washed away from the substrate 10 to be processed.

The substrate processing method includes a process S105 in which the dividing device 240 divides the thinned substrate 10 into a plurality of chips 40. The plurality of chips 40 are partitioned by, for example, a lattice-shaped through groove 18. The first main surface 41 of the chip 40 is the first main surface 11 of the substrate 10 to be processed. The second main surface 42 of the chip 40 is the second main surface 12 of the substrate 10 to be processed, and is a surface on which the first defect layer 51 is formed when the plate is thinned. The end surface 43 of the chip 40 is a side wall surface of the through groove 18 and is a surface on which the second defect layer 52 is formed at the time of division.

The substrate processing method includes a step S106 in which the etching apparatus 250 etches both the second main surface 42 of the chip 40 and the end face 43 of the chip 40. Since the first defect layer 51 formed on the second main surface 42 and the second defect layer 52 formed on the end face 43 can be removed by etching, the bending strength of the chip 40 can be improved. In addition, since the debris 53 attached to the second main surface 42 can be removed by etching, the cleanliness of the chip 40 can be improved. Although described in detail later, the debris 53 is generated at the time of division and adheres to the second main surface 42.

The substrate processing method includes a step S107 in which the gettering layer forming apparatus 260 forms the gettering layer 55 on the second main surface 42 of the chip 40. The gettering layer 55 captures impurities such as heavy metals. Unlike the first defect layer 51 removed by the etching apparatus 250, the gettering layer 55 can capture impurities without substantially reducing the bending strength of the chip 40. The gettering layer 55 may be formed inside the chip 40 at a predetermined depth from the second main surface 42 of the chip 40.

The substrate processing method includes a step S108 in which the transfer apparatus 280 carries the substrate 10 to be carried out from the processing station 200 to the carry-in / out station 100. The transfer device 280 places the substrate 10 to be processed on the substrate stage 130 of the carry-in / out station 100. Thereafter, the transfer device 122 of the loading / unloading station 100 receives the substrate 10 to be processed from the substrate table 130 and stores it in the cassette 102 or the cassette 103 placed on the cassette table 110. Thereafter, the current process ends.

FIG. 3 is a side view showing an outer peripheral portion processing apparatus according to an embodiment. In FIG. 3, the broken line indicates the second main surface 12 of the substrate to be processed 10 when the thinning is completed. FIG. 4 is a plan view showing a substrate to be processed that has been processed by the outer peripheral processing apparatus according to the embodiment.

The outer peripheral portion processing apparatus 210 performs processing on the outer peripheral portion of the substrate to be processed 10 to stop the extension of the crack from the outer periphery of the target substrate 10 toward the radially inner side. For example, the outer peripheral portion processing apparatus 210 forms the modified layer 15 on the outer peripheral portion of the substrate to be processed 10 that stops the extension of cracks from the outer periphery of the substrate to be processed 10 toward the radially inner side.

The outer peripheral portion processing apparatus 210 forms the modified layer 15 in an annular line L1 (see FIG. 4) that is a certain distance away from the outer periphery of the substrate 10 to be processed in the radial direction. The modified layer 15 may be formed continuously in the line L1, or may be formed discontinuously with an interval in the line L1. The annular line L <b> 1 is set on the outer side in the radial direction than the chip region 13. This is to prevent the chip area 13 from being damaged.

According to the present embodiment, when a crack extends from the outer periphery of the substrate 10 to be processed in the radial direction and the crack reaches the line L1, the extension direction of the crack changes from the radial direction to the circumferential direction. This is because cracks tend to extend in the direction of weak strength. As a result, the extension of the crack from the outer periphery of the substrate to be processed 10 toward the radially inner side can be stopped, and damage to the chip region 13 can be suppressed.

Here, the cracks directed radially inward from the outer periphery of the substrate 10 to be processed are formed, for example, when the substrate 10 to be processed is thinned. This is because when the substrate 10 to be processed is thinned, a knife edge-shaped portion 16 (see FIG. 3) is formed on the outer peripheral portion of the substrate 10 to be processed, and this portion 16 is easily chipped. This portion 16 is formed in a portion called a bevel. The bevel is a chamfered portion. In FIG. 3, the bevel is a portion subjected to R chamfering, but may be a portion subjected to C chamfering.

The outer peripheral portion processing apparatus 210 includes, for example, a processing chuck 211 and a processing head 212. The processing chuck 211 rotates while holding the substrate to be processed 10 horizontally with the second main surface 12 of the substrate to be processed 10 facing upward. The processing head 212 includes a condenser lens 213 that irradiates the laser beam LB1 from above toward the second main surface 12 of the substrate 10 to be processed held by the processing chuck 211.

The condensing lens 213 condenses the laser beam LB1 inside the substrate 10 to be processed, and forms the modified layer 15 inside the substrate 10 to be processed. As the laser beam LB1, one having transparency to the substrate 10 to be processed is used. The modified layer 15 is formed, for example, by locally melting and solidifying the inside of the substrate 10 to be processed.

The modified layer 15 is formed to a preset depth from the second main surface 12 of the substrate 10 to be processed. A plurality of modified layers 15 may be formed at different positions in the depth direction. That is, the plurality of modified layers 15 may be arranged at intervals in the depth direction.

The depth of the modified layer 15 is set as follows. When the substrate 10 is thinned, the substrate 10 is pushed in the plate thickness direction by the rotating grindstone 224 (see FIG. 5), so that the crack 17 (see FIG. 5) starts from the modified layer 15 in the plate thickness direction. Extend. During the thinning, the crack 17 reaches both the first main surface 11 of the substrate to be processed 10 and the second main surface 12 when the thinning of the substrate to be processed 10 is completed. Depth is set. Since the crack 17 penetrates the substrate to be processed 10 in the plate thickness direction, the extension of the crack from the outer periphery of the substrate to be processed 10 to the inside in the radial direction can be stopped over the entire plate thickness direction of the substrate to be processed 10.

The thin plate apparatus 220 thins the substrate 10 to be processed by grinding the second main surface 12 of the substrate 10 to be processed. As shown in FIG. 1, the thinning device 220 is disposed on the X axis direction positive side of the outer peripheral portion processing apparatus 210, and is disposed on the opposite side of the conveyance region 283 across the outer peripheral portion processing apparatus 210. Since the thin plate forming apparatus 220 is far from the cassette table 110, it is possible to suppress the grinding dust generated by the thin plate forming apparatus 220 from adhering to the substrate 10 after processing.

As shown in FIG. 1, for example, the thinning device 220 includes a rotary table 221, four rotary chucks 222, a primary processing unit 223, a secondary processing unit 225, and a tertiary processing unit 226.

The rotary table 221 is rotated around the vertical axis. Around the rotation center line of the rotary table 221, four rotary chucks 222 are arranged at equal intervals. Each of the four rotary chucks 222 rotates together with the rotary table 221 and moves to the delivery position D0, the primary machining position D1, the secondary machining position D2, and the tertiary machining position D3.

The delivery position D0 includes a position where the second transport unit 282 places the substrate 10 to be processed before thinning on the rotary chuck 222, and a position where the second transport unit 282 receives the substrate 10 after thinning from the rotary chuck 222. Doubles as The primary processing position D1 is a position where the primary processing unit 223 performs primary processing (for example, primary grinding). The secondary processing position D2 is a position where the secondary processing unit 225 performs secondary processing (for example, secondary grinding). The tertiary processing position D3 is a position where the tertiary processing unit 226 performs tertiary processing (for example, tertiary grinding).

The four rotary chucks 222 are attached to the rotary table 221 so as to be rotatable around the respective rotation center lines. Each of the four rotating chucks 222 is rotated while the substrate 10 to be processed being processed is processed by the processing unit. During this time, the rotation of the turntable 221 is prohibited.

Each of the four rotating chucks 222 holds the substrate 10 to be processed horizontally from below. Each of the four rotary chucks 222 has a circular suction surface having a diameter larger than the diameter of the substrate to be processed 10, and sucks the substrate to be processed 10 on the suction surface.

FIG. 5 is a side view showing a state during the processing of the primary processing unit of the thinning device according to the embodiment. In FIG. 5, a broken line shows the 2nd main surface 12 of the to-be-processed substrate 10 at the time of completion of thickness reduction. As shown in FIG. 5, the primary processing unit 223 performs primary grinding of the substrate 10 to be processed. The primary processing unit 223 has a rotating grindstone 224. The rotating grindstone 224 descends while rotating and grinds the upper surface (second main surface 12) of the substrate 10 to be processed that rotates together with the rotating chuck 222.

Since the secondary processing unit 225 and the tertiary processing unit 226 are configured in the same manner as the primary processing unit 223, illustration is omitted. However, the average grain size of the abrasive grains of the rotary grindstone of the secondary processing unit 225 is smaller than the average grain diameter of the abrasive grains of the rotary grindstone 224 of the primary machining unit 223. Moreover, the average particle diameter of the abrasive grains of the rotary grindstone of the tertiary processing unit 226 is smaller than the average grain diameter of the abrasive grains of the rotary grindstone of the secondary machining unit 225.

Note that the number of processing units for processing the substrate to be processed 10 is not limited to three, and may be one or two, or four or more. Further, the number of rotating chucks 222 only needs to be one more than the number of processing units.

The thinning device 220 only needs to have a grinding unit for grinding the substrate 10 to be processed. A first defect layer 51 is formed on the second main surface 12 of the substrate 10 to be processed by contact with the rotating grindstone 224. The first defect layer 51 includes a defect, and the defect reduces the bending strength of the chip 40.

The cleaning apparatus 230 cleans the substrate 10 to be processed after the substrate 10 is thinned and before the substrate 10 is divided. Thereby, grinding scraps generated by thinning the substrate to be processed 10 can be washed away from the substrate 10 to be processed.

The cleaning device 230 has a bottom surface cleaning unit. The lower surface cleaning unit cleans the support substrate 20 bonded to the lower surface (first main surface 11) of the substrate 10 to be processed. The lower surface cleaning unit includes, for example, a brush that contacts the support substrate 20 and a cleaning liquid nozzle that supplies a cleaning liquid to the brush.

While the lower surface cleaning unit cleans the support substrate 20, the suction pad of the second transport unit 282 sucks the substrate to be processed 10 from above with the first main surface 11 of the substrate to be processed 10 facing down. The second transport unit 282 transports the target substrate 10 cleaned by the lower surface cleaning unit to the upper surface cleaning unit.

The lower surface cleaning unit also has a function of cleaning the suction surface (lower surface) of the suction pad of the second transport unit 282 while the suction pad of the second transport unit 282 is not sucking the substrate 10 to be processed.

The cleaning device 230 has an upper surface cleaning unit. The upper surface cleaning unit cleans the ground upper surface (second main surface 12) of the substrate 10 to be processed. The upper surface cleaning unit includes, for example, a spin chuck that holds the substrate 10 to be processed from below, and a cleaning liquid nozzle that supplies a cleaning liquid to the upper surface of the substrate 10 that rotates together with the spin chuck.

FIG. 6 is a side view showing a dividing apparatus according to an embodiment. The dividing device 240 divides the thinned substrate 10 into a plurality of chips 40. A device is formed on the first main surface 41 of the chip 40 after division, and a first defect layer 51 is formed on the second main surface 42 of the chip 40 after division. The dividing device 240 includes, for example, a processing stage 241 and a processing head 242.

The processing stage 241 holds the target substrate 10 horizontally with the second main surface 12 of the target substrate 10 facing upward. The processing stage 241 holds the substrate 10 to be processed from below via the support substrate 20. The processing stage 241 has a circular suction surface having a diameter larger than the diameter of the substrate to be processed 10, and sucks the substrate to be processed 10 on the suction surface. The processing stage 241 is, for example, an XYθ stage, and is movable in the X axis direction, the Y axis direction, and the θ direction.

The processing head 242 has a condensing lens 243 that irradiates the second main surface 12 of the substrate 10 to be processed with the laser beam LB2. The condensing lens 243, for example, condenses the laser beam LB2 on the second main surface 12 of the substrate to be processed 10 and forms the through groove 18 penetrating the substrate to be processed 10 in the plate thickness direction. As the laser beam LB2, one having an absorptivity with respect to the substrate to be processed 10 is used. The through groove 18 is formed, for example, by locally sublimating the substrate 10 to be processed.

The dividing device 240 moves the irradiation point of the laser beam LB2 on the upper surface of the substrate to be processed 10 by moving the processing stage 241 in the X-axis direction, the Y-axis direction, and the θ direction, for example. The moving path of the irradiation point of the laser beam LB2 is set so as to coincide with the planned dividing line 14. As a result, a lattice-like through groove 18 that partitions the plurality of chips 40 is formed.

The dividing device 240 is a laser dicing device in the present embodiment, but may be a blade dicing device. In the latter case, the machining head 242 rotatably supports a disk-shaped blade. The blade divides the substrate to be processed 10 into a plurality of chips 40.

The first main surface 41 of the chip 40 is the first main surface 11 of the substrate to be processed 10 and is a surface on which a device is formed. The second main surface 42 of the chip 40 is the second main surface 12 of the substrate 10 to be processed and is a surface ground by the thinning device 220. The end surface 43 of the chip 40 is a divided surface divided by the dividing device 240 and is a side wall surface of the through groove 18.

The debris 53 adheres to the second main surface 42 of the chip 40 regardless of whether the dividing device 240 is a laser dicing device or a blade dicing device. The debris 53 is dust generated by the division of the substrate 10 to be processed, and reduces the cleanliness of the substrate 10 to be processed. When the dividing device 240 is a laser dicing device, the debris 53 is obtained by cooling and solidifying the sublimated gas of the substrate 10 to be processed. On the other hand, when the dividing device 240 is a blade dicing device, the debris 53 is cutting waste of the substrate 10 to be processed.

In addition, the second defect layer 52 is formed on the end face 43 of the chip 40 regardless of whether the dividing device 240 is a laser dicing device or a blade dicing device. The second defect layer 52 includes a defect, and the defect reduces the bending strength of the chip 40. When the dividing device 240 is a laser dicing device, the defect of the second defect layer 52 is formed by the heat of the laser beam LB3. On the other hand, when the dividing device 240 is a blade dicing device, the defect of the second defect layer 52 is formed by contact with the blade.

FIG. 7 is a side view showing an etching apparatus according to an embodiment. The etching apparatus 250 etches both the second main surface 42 of the chip 40 and the end face 43 of the chip 40. Since the first defect layer 51 formed on the second main surface 42 and the second defect layer 52 formed on the end face 43 can be removed by etching, the bending strength of the chip 40 can be improved. The first defect layer 51 and the second defect layer 52 may be at least partially removed, but preferably all are removed. In addition, since the debris 53 attached to the second main surface 42 can be removed by etching, the cleanliness of the chip 40 can be improved. The debris 53 may be at least partially removed, but preferably is entirely removed.

The etching apparatus 250 is, for example, a wet etching apparatus, and includes a rotary chuck 251 and an etchant nozzle 252. The rotating chuck 251 rotates while holding the substrate to be processed 10 with the second main surface 12 of the substrate to be processed 10 (that is, the second main surface 42 of the chip 40) facing upward.

The etching solution nozzle 252 discharges the etching solution 253 to the center of the second main surface 12 of the substrate to be processed 10 that rotates together with the rotary chuck 251. The etching solution 253 spreads from the radially inner side to the radially outer side by centrifugal force, wets and spreads over the entire second main surface 12 of the substrate to be processed 10, and enters the lattice-shaped through grooves 18. Etching solution 253 etches second main surface 42 and end surface 43.

The etching solution 253 may be an alkaline aqueous solution or an acidic aqueous solution. Examples of the alkaline aqueous solution include TMAH (tetramethylammonium hydroxide: (CH ₃ ) ₄ NOH) aqueous solution and choline aqueous solution. Examples of the acidic aqueous solution include a hydrofluoric acid (HF) aqueous solution, a nitric acid (HNO ₃ ) aqueous solution, and a phosphoric acid (H ₃ P0 ₄ ) aqueous solution.

Etching solution 253 may be an anisotropic etching solution or an isotropic etching solution.

The etching solution 253 may include a plurality of etching materials, for example, an aqueous solution including hydrofluoric acid, nitric acid, and acetic acid (CH ₃ COOH). By adjusting the mixing ratio of hydrofluoric acid, nitric acid and acetic acid, the etching rate and the surface roughness of the etched surface can be adjusted.

The etching apparatus 250 is a wet etching apparatus in the present embodiment, but may be a dry etching apparatus. The dry etching apparatus may use plasma or may not use plasma.

As a dry etching material that does not use plasma, for example, chlorine trifluoride (ClF ₃ ) gas is used. On the other hand, as a material for dry etching using plasma, for example, a mixed gas of sulfur hexafluoride (SF ₆ ) gas, oxygen gas, and fluorine gas is used.

FIG. 8 is a side view showing a gettering layer forming apparatus according to an embodiment. The gettering layer forming apparatus 260 forms the gettering layer 55 on the second main surface 42 of the chip 40. The gettering layer 55 includes gettering sites (for example, crystal defects and strains) for trapping impurities. The impurities are, for example, heavy metals such as copper (Cu), iron (Fe), nickel (Ni), or chromium (Cr).

The gettering layer 55 is formed on the second main surface 42 of the chip 40, for example, as shown in FIG. The second main surface 42 of the chip 40 is the second main surface 12 of the substrate 10 to be processed and is a surface etched by the etching apparatus 250 after being ground by the thinning apparatus 220. The gettering layer 55 captures impurities, thereby limiting the diffusion of impurities into the device and reducing device characteristic defects.

Unlike the first defect layer 51 removed by the etching apparatus 250, the gettering layer 55 can trap impurities without substantially reducing the bending strength of the chip 40. Although the first defect layer 51 can capture impurities, the bending strength of the chip 40 is greatly reduced.

Unlike the first defect layer 51 removed by the etching apparatus 250, the gettering layer 55 is formed by locally melting and solidifying the substrate to be processed 10, and is uniformly formed at a predetermined position. . Therefore, there is no deep flaw formed unintentionally, and the bending strength of the chip 40 is hardly lowered.

Further, unlike the second defect layer 52 removed by the etching apparatus 250, the gettering layer 55 locally melts and solidifies the target substrate 10 without locally sublimating the target substrate 10. It is formed by. Therefore, the integrated irradiation amount of the laser beam LB3 applied to the substrate 10 to be processed is small, and the bending strength of the chip 40 hardly decreases.

In the present specification, the unit of irradiation amount is J / mm ² . Further, the integrated irradiation amount is the total irradiation amount.

The gettering layer forming apparatus 260 includes, for example, a substrate holding unit 261, a parallel movement mechanism unit 262 (see FIG. 9), a rotational movement mechanism unit 265 (see FIG. 9), a light source unit 267, and an optical unit 270. Have.

The substrate holding unit 261 holds the substrate to be processed 10. For example, the substrate holding unit 261 holds the target substrate 10 horizontally with the second main surface 12 of the target substrate 10 facing upward. The substrate holding unit 261 holds the substrate 10 to be processed from below via the support substrate 20.

The substrate holding unit 261 has a circular suction surface having a diameter larger than the diameter of the substrate to be processed 10 and sucks the substrate to be processed 10 on the suction surface. The substrate holding unit 261 is, for example, an XYθ stage, and is movable in the X axis direction, the Y axis direction, and the θ direction.

The parallel movement mechanism unit 262 includes an X-axis direction movement mechanism unit 263 that moves the substrate holding unit 261 in the X-axis direction. The X-axis direction moving mechanism unit 263 includes, for example, a rotary motor and a ball screw that converts the rotary motion of the rotary motor into the linear motion of the substrate holding unit 261.

The parallel movement mechanism unit 262 includes a Y-axis direction movement mechanism unit 264 that moves the substrate holding unit 261 in the Y-axis direction. The Y-axis direction moving mechanism unit 264 includes, for example, a rotary motor and a ball screw that changes the rotary motion of the rotary motor to the linear motion of the substrate holding unit 261.

The rotation moving mechanism unit 265 rotates the substrate holding unit 261 in the θ direction. The rotational movement mechanism unit 265 includes, for example, a rotation motor and a timing belt that transmits the rotational motion of the rotation motor to the substrate holding unit 261. A gear or the like may be used instead of the timing belt.

The light source unit 267 (see FIG. 8) is a laser oscillator that oscillates the laser beam LB3. The laser beam LB3 forms the gettering layer 55 by locally melting and solidifying the substrate 10 to be processed. As the laser beam LB3, one having an absorptivity with respect to the substrate to be processed 10 is used.

The optical unit 270 irradiates the target substrate 10 held by the substrate holding unit 261 with the laser beam LB3. An irradiation point 60 of the laser beam LB3 is formed on the second main surface 12 of the substrate 10 to be processed. By moving the irradiation point 60, the gettering layer 55 is formed in the movement range of the irradiation point 60.

The optical unit 270 has a scanning mechanism 271 that moves the irradiation point 60 of the laser beam LB3 on the substrate 10 to be processed. The irradiation point 60 can be moved horizontally without moving the substrate holder 261 horizontally. Therefore, the movement range of the substrate holding part 261 can be reduced, and the gettering layer forming apparatus 260 can be downsized.

The scanning mechanism 271 includes, for example, a galvanometer mirror unit 272. The galvanometer mirror unit 272 includes a galvanometer mirror 273 that reflects the laser beam LB3, and a galvano motor 274 that rotates the galvanometer mirror 273.

The scanning mechanism 271 moves the irradiation point 60 horizontally by changing the rotation angle of the galvanometer mirror 273 under the control of the control device 300. The scanning mechanism 271 has two sets of galvanometer mirrors 273 and galvanomotors 274 (only one set is shown in FIG. 8) in order to move the irradiation point 60 in both the X-axis direction and the Y-axis direction.

Note that the scanning mechanism 271 may include a polygon mirror instead of the galvanometer mirror 273.

The scanning mechanism 271 further includes an fθ lens 275. The fθ lens 275 places the focal point of the laser beam LB3 on one plane while the irradiation point 60 of the laser beam LB3 is moving. The focal plane of the fθ lens 275 is set to, for example, the second main surface 12 of the substrate 10 to be processed, that is, the second main surface 42 of the chip 40. As a result, the gettering layer 55 is formed on the second main surface 42 of the chip 40.

It should be noted that the focal plane of the fθ lens 275 may be set so as to be shifted in parallel from the second main surface 42 of the chip 40. For example, the focal plane of the fθ lens 275 may be set between the second main surface 42 and the first main surface 41. In this case, the gettering layer 55 can be formed at a predetermined depth from the second main surface 42.

The fθ lens 275 may include a telecentric lens. The telecentric lens irradiates the laser beam LB3 perpendicularly to the focal plane of the fθ lens 275. While the irradiation point 60 is moving, the shape change of the irradiation point 60 can be suppressed.

The optical unit 270 includes a homogenizer 277 that forms the cross-sectional shape of the laser beam LB3 in a rectangular shape and makes the cross-sectional intensity distribution of the laser beam LB3 uniform. The shape of the irradiation point 60 can be shaped into a rectangular shape, and the intensity distribution of the irradiation point 60 can be made uniform. Therefore, a uniform gettering layer 55 can be formed.

Next, an example of control of the gettering layer forming apparatus 260 will be described with reference to FIG. FIG. 9 is a plan view showing a gettering layer forming apparatus according to an embodiment. As shown in FIG. 9, the substrate 10 to be processed is equally divided into four in the circumferential direction in plan view, and the first divided area A1, the second divided area A2, the third divided area A3, and the fourth divided area. Divided into A4.

First, a method for forming the gettering layer 55 in the first divided region A1 will be described with reference to FIGS. FIG. 10A is a plan view showing a state when the gettering layer is formed in the first scan region that is a part of the first divided region according to the embodiment. FIG. 10B is a diagram illustrating a state when the gettering layer is formed in the second scan region that is a part of the first divided region according to the embodiment. FIG. 11A is a diagram illustrating a state when the gettering layer is formed in the third scan region that is a part of the first divided region according to the embodiment. FIG. 11B is a diagram illustrating a state when the gettering layer is formed in the fourth scan region that is a part of the first divided region according to the embodiment.

The first divided area A1 is divided into, for example, a first scan area B1, a second scan area B2, a third scan area B3, and a fourth scan area B4. The first scan area B1, the second scan area B2, the third scan area B3, and the fourth scan area B4 are each set smaller than the fθ lens 275 in plan view.

First, the control device 300 moves the irradiation point 60 two-dimensionally in the X-axis direction and the Y-axis direction by the scan mechanism 271 while the substrate holding unit 261 is stopped, thereby obtaining the getter in the first scan region B1. A ring layer 55 is formed. While the gettering layer 55 is formed in the first scan region B1, the first scan region B1 is arranged on the inner side of the outer periphery of the fθ lens 275 in plan view as shown in FIG.

Next, the control device 300 moves the substrate holding part 261 horizontally and arranges the second scan region B2 inside the outer periphery of the fθ lens 275 in plan view as shown in FIG. Subsequently, the control device 300 moves the irradiation point 60 two-dimensionally in the X-axis direction and the Y-axis direction by the scan mechanism 271 while the substrate holding unit 261 is stopped, so that the second scan region B2 is moved. A gettering layer 55 is formed.

Next, the control device 300 moves the substrate holding portion 261 horizontally, and arranges the third scan region B3 inside the outer periphery of the fθ lens 275 in plan view as shown in FIG. Subsequently, the control device 300 moves the irradiation point 60 two-dimensionally in the X-axis direction and the Y-axis direction by the scan mechanism 271 in a state where the substrate holding unit 261 is stopped, thereby moving to the third scan region B3. A gettering layer 55 is formed.

Finally, the control device 300 moves the substrate holder 261 horizontally, and arranges the fourth scan region B4 on the inner side of the outer periphery of the fθ lens 275 in plan view as shown in FIG. Subsequently, the control device 300 moves the irradiation point 60 two-dimensionally in the X-axis direction and the Y-axis direction by the scan mechanism 271 in a state where the substrate holding unit 261 is stopped, thereby moving to the fourth scan region B4. A gettering layer 55 is formed.

As described above, the control device 300 alternates between the control for moving the irradiation point 60 two-dimensionally by the scanning mechanism 271 while the substrate holding unit 261 is stopped and the control for moving the substrate holding unit 261 in parallel. Repeat. The control device 300 switches the region in which the irradiation point 60 is moved two-dimensionally by the scan mechanism 271 of the substrate 10 to be processed held by the substrate holding unit 261 by moving the substrate holding unit 261 in parallel. The first divided region A1 is divided into a plurality of regions, and a gettering layer 55 is formed for each divided region. Therefore, the diameter of the fθ lens 275 can be set smaller than the radius of the substrate 10 to be processed. Therefore, the cost of the fθ lens 275 can be reduced.

Note that the method of forming the gettering layer 55 in the first divided region A1 is not limited to the above method. For example, the control device 300 may two-dimensionally move the irradiation point 60 to the entire first divided area A1 by the scan mechanism 271 with the substrate holding unit 261 stopped. In this case, the diameter of the fθ lens 275 is set to be large so that the entire first divided region A1 can be disposed inside the outer periphery of the fθ lens 275 in plan view. However, in this case, it is not necessary to translate the substrate holding portion 261 while the gettering layer 55 is formed in the entire first divided region A1. Therefore, the parallel movement mechanism unit 262 is not necessary, and the structure of the gettering layer forming apparatus 260 can be simplified.

The control device 300 executes the control of rotating the substrate holding part 261 by 90 ° after forming the gettering layer 55 in the first divided area A1. Thereby, the scanning mechanism 271 can move the irradiation point 60 in the second divided region A2. Thereafter, the control device 300 executes control for forming the gettering layer 55 in the second divided region A2. Since the control for forming the gettering layer 55 in the second divided region A2 is the same as the control for forming the gettering layer 55 in the first divided region A1, description thereof is omitted.

The control device 300 executes the control of rotating the substrate holding part 261 by 90 ° after forming the gettering layer 55 in the second divided region A2. As a result, the scanning mechanism 271 can move the irradiation point 60 in the third divided region A3. Thereafter, the control device 300 executes control for forming the gettering layer 55 in the third divided region A3. Since the control for forming the gettering layer 55 in the third divided region A3 is the same as the control for forming the gettering layer 55 in the first divided region A1, description thereof is omitted.

The control device 300 executes the control of rotating the substrate holding part 261 by 90 ° after forming the gettering layer 55 in the third divided region A3. Thereby, the scanning mechanism 271 can move the irradiation point 60 in the fourth divided region A4. Thereafter, the control device 300 executes control for forming the gettering layer 55 in the fourth divided region A4. Since the control for forming the gettering layer 55 in the fourth divided region A4 is the same as the control for forming the gettering layer 55 in the first divided region A1, description thereof is omitted.

As described above, the control device 300 alternates between the control for moving the irradiation point 60 two-dimensionally by the scan mechanism 271 and the control for rotating the substrate holding unit 261 while the substrate holding unit 261 is stopped. Repeat. The control device 300 switches the region in which the irradiation point 60 is moved two-dimensionally by the scan mechanism 271 of the substrate 10 to be processed held by the substrate holding unit 261 by rotating the substrate holding unit 261. The substrate 10 to be processed is divided into a plurality of regions, and a gettering layer 55 is formed in each divided region. Therefore, the diameter of the fθ lens 275 can be set smaller than the diameter of the substrate 10 to be processed. Therefore, the cost of the fθ lens 275 can be reduced.

In addition, although the to-be-processed substrate 10 of this embodiment is equally divided into four in the circumferential direction, it may be equally divided into two in the circumferential direction. In any case, the diameter of the fθ lens 275 can be set smaller than the diameter of the substrate 10 to be processed. Therefore, the cost of the fθ lens 275 can be reduced.

Next, an example of control of the scan mechanism 271 will be described with reference to FIG. FIG. 12 is a plan view illustrating an example of control of the scanning mechanism. FIG. 12A is a plan view showing an example of the formation position of the irradiation point k (k is a natural number of 1 or more). FIG. 12B is a plan view showing an example of the formation position of the (k + 1) th irradiation point. FIG. 12C is a plan view showing an example of the formation position of the (k + 2) th irradiation point. FIG. 12D is a plan view showing an example of the formation position of the irradiation point of the (k + 3) th time. As illustrated in FIG. 12, the control device 300 repeatedly performs the formation of the irradiation point 60 of the laser beam LB3 while shifting the position of the irradiation point 60 in a state where the substrate holding unit 261 is stopped.

In this specification, the position of the irradiation point 60 is the position of the irradiation point 60 on the substrate 10 to be processed held by the substrate holding unit 261. The control device 300 moves the position of the irradiation point 60 by controlling the scan mechanism 271.

The control device 300 prohibits movement of the position of the irradiation point 60 in a state where the irradiation point 60 of the laser beam LB3 is formed. For example, when the position of the irradiation point 60 is shifted, the control device 300 stops the output of the laser beam LB3 from the light source unit 267.

The control device 300 shifts the formation position of the irradiation point 60 in parallel with one side 61 of the rectangular irradiation point 60, for example, by controlling the scanning mechanism 271. The amount E of shifting the formation position of the irradiation point 60 between the k-th time and the (k + 1) -th time is, for example, half of the length F of the side 61. Thereby, the same position of the substrate 10 can be irradiated with the laser beam LB3 a plurality of times. Therefore, the irradiation amount of the laser beam LB3 per time can be reduced, and the reduction in the bending strength of the chip 40 can be limited.

Next, another example of control of the scan mechanism 271 will be described with reference to FIG. FIG. 13 is a plan view showing another example of control of the scanning mechanism. FIG. 13A is a plan view showing an example of the formation position of the irradiation point of the kth (k is a natural number of 1 or more). FIG. 13B is a plan view showing an example of the formation position of the (k + 1) th irradiation point. FIG. 13C is a plan view showing an example of the formation position of the irradiation point of the 1st (l is a natural number larger than k + 1) times. FIG. 13D is a plan view showing an example of the formation position of the l + 1th irradiation point. As illustrated in FIG. 13, the control device 300 repeatedly performs the formation of the irradiation point 60 of the laser beam LB3 while shifting the position of the irradiation point 60 in a state where the substrate holding unit 261 is stopped.

The control device 300 shifts the formation position of the irradiation point 60 in parallel with one side 61 of the rectangular irradiation point 60, for example, by controlling the scanning mechanism 271. The amount E of shifting the formation position of the irradiation point 60 between the k-th time and the k + 1-th time is the same as the length F of the side 61, for example. In this case, by forming the irradiation point 60 at the same position as the k-th time, the laser beam LB3 can be irradiated multiple times to the same position of the substrate 10 to be processed. Therefore, the irradiation amount of the laser beam LB3 per time can be reduced, and the reduction in the bending strength of the chip 40 can be limited.

The formation position of the kth irradiation point 60 and the formation position of the lth irradiation point 60 are completely overlapped in FIG. 13, but may be partially overlapped. For example, the formation position of the first irradiation point 60 may extend over both the formation position of the kth irradiation point 60 and the formation position of the (k + 1) th irradiation point 60. The amount E of shifting the formation position of the irradiation point 60 between the first time and the l + 1th time may be the same as the length F of the side 61.

As described above, the control device 300 irradiates the laser beam LB3 n times (n is a natural number of 2 or more) times in the same region (for example, a region indicated by hatching in FIGS. 12 and 13) of the substrate 10 to be processed. . Thereby, the irradiation amount of the laser beam LB3 per time can be reduced, and the decrease in the bending strength of the chip 40 due to the irradiation of the laser beam LB3 can be limited.

The control device 300 irradiates the same region of the substrate to be processed 10 with the laser beam LB3 at the mth (m is a natural number greater than or equal to 1 and less than or equal to n-1) times and the m + 1th time. The region heated by the irradiation with the laser beam LB3 is sufficiently cooled naturally, and then the same region is irradiated with the laser beam LB3. A decrease in the bending strength of the chip 40 due to the temperature rise can be limited.

Next, a modified example of the control of the gettering layer forming apparatus 260 will be described with reference to FIG. In this modification, unlike the example shown in FIGS. 12 and 13, the control device 300 moves the position of the irradiation point 60 in a state where the irradiation point 60 of the laser beam LB3 is formed. FIG. 14A is a diagram illustrating a state when a gettering layer is formed in the first region of the substrate to be processed according to the modification. FIG. 14B is a diagram showing a state when a gettering layer is formed in the second region of the substrate to be processed according to the modification.

First, the control device 300 rotates and moves the substrate holder 261 and reciprocates the laser beam LB3 in the radial direction (for example, the X-axis direction) of the substrate 10 to be processed held by the substrate holder 261. A gettering layer 55 is formed in the first region C1 of the processing substrate 10.

The rotational movement mechanism unit 265 may rotate the substrate holding unit 261 one or more times, or may rotate a plurality of times. In the meantime, the scanning mechanism 271 causes the laser beam LB3 to be emitted a plurality of times between the center position of the substrate 10 to be processed and the reversal position (position on the outer periphery of the first region C1) away from the center position of the substrate to be processed 10 Move back and forth.

The scanning mechanism 271 only needs to linearly move the laser beam LB3 on the target substrate 10 held by the substrate holding unit 261. Therefore, the scanning mechanism 271 has only one set of the galvano mirror 273 and the galvano motor 274. Therefore, the structure of the scan mechanism 271 can be simplified.

The control device 300 executes control to decrease the rotation speed of the substrate holding unit 261 as the irradiation point 60 of the laser beam LB3 is further away from the center of the substrate 10 to be processed. Or the control apparatus 300 performs control which makes the moving speed of the irradiation point 60 slow, so that the irradiation point 60 of the laser beam LB3 leaves | separates from the center of the to-be-processed substrate 10. FIG. The control device 300 performs at least one control among the control of the number of rotations of the substrate holding unit 261 and the control of the moving speed of the irradiation point 60. The integrated dose of the laser beam LB3 per unit area in the first region C1 can be made uniform, and a uniform gettering layer 55 can be formed in the first region C1.

The first region C1 is a circular region having a certain distance from the center of the substrate 10 to be processed. The diameter of the first region C1 may be the same as the diameter of the substrate 10 to be processed, but may be smaller than the diameter of the substrate 10 to be processed as shown in FIG.

As shown in FIG. 14, when the diameter of the first region C1 is smaller than the diameter of the substrate 10 to be processed, the diameter of the fθ lens 275 can be set smaller than the radius of the substrate 10 to be processed. Therefore, the cost of the fθ lens 275 can be reduced.

If the diameter of the first region C1 is the same as the diameter of the substrate 10 to be processed, the diameter of the fθ lens 275 is larger than the radius of the substrate 10 to be processed. However, in this case, since the linear movement of the substrate holding unit 261 described later is unnecessary, the parallel movement mechanism unit 262 is unnecessary.

Next, the control device 300 moves the substrate holder 261 in the linear movement direction (for example, the X-axis direction) of the laser beam LB3 when the gettering layer 55 is formed in the first region C1.

Next, the control device 300 rotates and moves the substrate holding unit 261 and reciprocally moves the laser beam LB3 in the radial direction of the substrate to be processed 10 held by the substrate holding unit 261. A gettering layer 55 is formed in the two regions C2.

The rotational movement mechanism unit 265 may rotate the substrate holding unit 261 one or more times, or may rotate a plurality of times. Meanwhile, the scanning mechanism 271 reciprocates the laser beam LB3 a plurality of times between the inner periphery position of the second region C2 and the outer periphery position of the second region C2.

The scanning mechanism 271 linearly moves the laser beam LB3 on the target substrate 10 held by the substrate holding unit 261. The linear movement direction may be the same as the linear movement direction when the gettering layer 55 is formed in the first region C1. The scanning mechanism 271 only needs to have one set of the galvano mirror 273 and the galvano motor 274. Therefore, the structure of the scan mechanism 271 can be simplified.

The control device 300 executes control to decrease the rotation speed of the substrate holding unit 261 as the irradiation point 60 of the laser beam LB3 is further away from the center of the substrate 10 to be processed. Or the control apparatus 300 performs control which makes the moving speed of the irradiation point 60 slow, so that the irradiation point 60 of the laser beam LB3 leaves | separates from the center of the to-be-processed substrate 10. FIG. The control device 300 performs at least one control among the control of the number of rotations of the substrate holding unit 261 and the control of the moving speed of the irradiation point 60. The integrated irradiation amount of the laser beam LB3 per unit area in the second region C2 can be made uniform, and a uniform gettering layer 55 can be formed in the second region C2.

The integrated irradiation amount of the laser beam LB3 per unit area in the second region C2 may be the same as the integrated irradiation amount of the laser beam LB3 per unit area in the first region C1. A uniform gettering layer 55 can be formed on the entire substrate 10 to be processed.

The second region C2 is an annular region that is concentric with the first region C1. The outer diameter of the second region C2 may be the same as the diameter of the substrate to be processed 10 as shown in FIG. 14, but may be smaller than the diameter of the substrate to be processed 10.

When the diameter of the second region C2 is smaller than the diameter of the substrate 10 to be processed, the third region is set outside the second region C2. The third region is a concentric annular region with the first region C1 and the second region C2. In this case, the control device 300 forms the gettering layer 55 in the third region, similarly to the second region C2.

In this embodiment, the gettering layer 55 is formed in the second region C2 after the gettering layer 55 is formed in the first region C1, but the order may be reversed. That is, the control device 300 may form the gettering layer 55 in the first region C1 after forming the gettering layer 55 in the second region C2.

As mentioned above, although embodiment of the substrate processing system and substrate processing method concerning this indication was described, this indication is not limited to the above-mentioned embodiment etc. Various changes, modifications, substitutions, additions, deletions, and combinations can be made within the scope of the claims. Of course, these also belong to the technical scope of the present disclosure.

FIG. 15 is a plan view showing a substrate processing system according to a modification. A thinning apparatus 220 of the substrate processing system 1 shown in FIG. 15 includes a laser processing apparatus 510 and a thinning dividing apparatus 520. As shown in FIG. 16, the laser processing apparatus 510 forms a condensing point P of the laser beam LB4 on the first division planned surface S1 in the thickness direction of the substrate 10 to be processed, and the first modified layer at the condensing point P. M1 is formed. As shown in FIG. 17, the thinning dividing apparatus 520 divides the substrate 10 to be processed on the first division planned surface S <b> 1. As a result, the substrate 10 to be processed is thinned.

FIG. 16 is a side view showing an example of the laser processing apparatus shown in FIG. The substrate 10 to be processed is a semiconductor substrate such as a silicon wafer or a compound semiconductor wafer. On one side of the substrate 10 to be processed, a device layer 71 is formed in advance as shown in FIG. The device layer 71 is, for example, an electronic circuit. The main surface on which the device layer 71 of the substrate 10 is formed is also referred to as the first main surface 11. The main surface opposite to the first main surface 11 is also referred to as a second main surface 12. The second main surface 12 approaches the first main surface 11 by thinning the substrate 10 to be processed.

An oxide layer 72 is formed on the surface of the device layer 71 opposite to the substrate 10 to be processed. The oxide layer 72 is formed smaller than the diameter of the substrate to be processed 10 in order to smoothly remove the bevel 19 of the substrate to be processed 10. The bevel 19 is a portion that has been chamfered. The oxide layer 72 is a silicon oxide layer, for example. The silicon oxide layer is made of, for example, tetraethyl orthosilicate (TEOS).

The support substrate 20 is a semiconductor substrate such as a silicon wafer or a compound semiconductor wafer, like the substrate 10 to be processed. Note that the support substrate 20 may be a glass substrate. The support substrate 20 is bonded to the substrate to be processed 10 via the device layer 71.

An oxide layer 73 is formed on the surface of the support substrate 20 facing the device layer 71. The oxide layer 73 is formed in the same manner as the oxide layer 72. A device layer (not shown) may be formed between the oxide layer 73 and the support substrate 20.

The polymerization substrate 30 includes a substrate to be processed 10, a device layer 71, two

oxide layers

72 and 73, and a support substrate 20. The two

oxide layers

72 and 73 are combined by heat treatment. In addition, you may have only one of the superposition | polymerization board | substrate 30, and the two

oxide layers

72 and 73. FIG.

The laser processing apparatus 510 collects and irradiates the laser beam LB4 into the substrate to be processed 10 from the side opposite to the device layer 71 (for example, the upper side). The laser beam LB4 is pulse-oscillated and forms a modified layer at the position of the condensing point P. When the substrate 10 to be processed is single crystal silicon, infrared rays are used as the laser beam LB4. Infrared rays have high permeability to single crystal silicon, and an amorphous silicon layer is formed as a modified layer at the position of the infrared condensing point P. The modified layer is a starting point for dividing the substrate 10 to be processed. The substrate 10 to be processed is divided by applying stress.

The laser processing apparatus 510 forms the first modified layer M1 on the first division planned surface S1 that divides the substrate 10 to be processed in the plate thickness direction. The first division planned surface S1 is a flat surface parallel to the first main surface 11 and the second main surface 12 of the substrate 10 to be processed. The flat surface is concentric with the outer periphery of the substrate 10 to be processed. A plurality of the first modified layers M1 are formed at intervals in the circumferential direction and the radial direction of the first scheduled split surface S1. During the formation of the first modified layer M1, a first crack CR1 that connects the first modified layers M1 is generated.

The laser processing apparatus 510 forms the second modified layer M2 on the second division planned surface S2 that divides the substrate to be processed 10 in the radial direction. The second division planned surface S2 is a circumferential surface that is concentric with the outer periphery of the substrate 10 to be processed. A plurality of second modified layers M2 are formed at intervals in the circumferential direction and the plate thickness direction of the substrate 10 to be processed. During the formation of the second modified layer M2, a second crack CR2 that connects the second modified layers M2 occurs.

As shown in FIG. 16, for example, the first modified layer M1 is formed so that the first crack CR1 intersects the second division planned surface S2 and does not reach the outer periphery of the substrate 10 to be processed. The second modified layer M2 is formed such that the second crack CR2 reaches the first main surface 11 and does not reach the second main surface 12.

The laser processing apparatus 510 includes a chuck 511, a laser head 514, and an elevating mechanism 517. The chuck 511 holds the target substrate 10 horizontally from below with the second main surface 12 of the target substrate 10 facing upward. For example, the chuck 511 holds the substrate to be processed 10 via the support substrate 20 and the device layer 71. The chuck 511 rotates around a vertical rotation axis 512. Further, the chuck 511 moves along a guide rail 513 extending in the X-axis direction. By rotating and moving the chuck 511, the position of the light condensing point P can be moved in the circumferential direction and the radial direction of the substrate 10 to be processed.

Note that the chuck 511 may move in the Y-axis direction instead of rotating around the rotation axis 512. Also in this case, the position of the condensing point P can be moved in the circumferential direction and the radial direction of the substrate 10 to be processed. The chuck 511 may also move in the Z-axis direction. In this case, the position of the condensing point P can also be moved in the thickness direction of the substrate 10 to be processed.

The laser head 514 has a condenser lens 515. The condensing lens 515 collects and irradiates the laser beam LB4 inside the substrate to be processed 10 from the side opposite to the device layer 71 (for example, the upper side) with respect to the substrate 10 to be processed, and the first inside the substrate 10 to be processed. The modified layer M1 and the second modified layer M2 are formed. The first modified layer M1 and the second modified layer M2 are formed at the position of the condensing point P.

The laser head 514 has a spatial light modulator 516. The spatial light modulator 516 controls the spatial distribution of the laser beam LB4. The spatial distribution includes, for example, phase, polarization plane, amplitude, intensity, and propagation direction. The spatial light modulator 516 includes, for example, LCOS (Liquid Crystal on Silicon). The spatial light modulator 516 can adjust the depth from the second main surface 12 of the substrate to be processed 10 to the condensing point P. Further, the spatial light modulator 516 can adjust at least one of the shape and the number of the laser beams LB4 irradiated on the substrate 10 to be processed. The spatial light modulator 516 can irradiate a plurality of points with the laser beam LB4 simultaneously.

The elevating mechanism 517 moves the laser head 514 up and down. Thereby, the depth of the condensing point P can be adjusted. The elevating mechanism 517 may elevate and lower the chuck 511 in order to adjust the depth of the condensing point P. In this modification, a spatial light modulator 516 and an elevating mechanism 517 are used as an adjusting unit that adjusts the depth of the condensing point P.

FIG. 17 is a side view showing an example of the dividing apparatus for thinning shown in FIG. The thinning dividing apparatus 520 includes a first chuck 521 and a second chuck 522. The first chuck 521 holds the target substrate 10 horizontally from below with the second main surface 12 of the target substrate 10 facing upward. The first chuck 521 has a circular suction surface having a diameter larger than the diameter of the substrate to be processed 10 and sucks the substrate to be processed 10 on the suction surface. The first chuck 521 holds the substrate to be processed 10 via the device layer 71. The support substrate 20 is disposed between the device layer 71 and the first chuck 521.

The second chuck 522 sucks the substrate 10 to be processed from the side opposite to the device layer 71. The second chuck 522 has a circular suction surface having a diameter larger than the diameter of the substrate 10 to be processed, and sucks the substrate 10 to be processed on the suction surface. The second chuck 522 can move in the horizontal direction (both in the X-axis direction and the Y-axis direction) and the vertical direction, and can turn around the vertical axis.

The second chuck 522 is raised while the second chuck 522 sucks the substrate 10 to be processed from above and the first chuck 521 sucks the substrate 10 to be processed from below. As a result, stress is applied to the substrate 10 to be processed, the first crack CR1 spreads in a planar shape, and the adjacent first cracks CR1 are connected to each other. The processing substrate 10 is thinned. Further, since stress is applied to the substrate 10 to be processed, the second crack CR2 spreads in a plane shape, and the adjacent second cracks CR2 are connected to each other, so that the substrate to be processed 10 is divided at the second scheduled division surface S2. The bevel 19 is removed from the substrate 10.

The second chuck 522 may be raised while rotating around the vertical rotation shaft 523 so as to thread the substrate 10 to be processed by the first division planned surface S1 and the second division planned surface S2. Instead of the second chuck 522, the first chuck 521 may rotate around the rotation shaft 524. Further, the second chuck 522 and the first chuck 521 may rotate in opposite directions.

The thin plate forming apparatus 220 may further include a thin plate forming etching apparatus 530 as shown in FIG. The thin plate etching apparatus 530 etches the second main surface 12 divided by the thin plate dividing apparatus 520 of the substrate to be processed 10 and smoothes the second main surface 12. The thinning device 220 may further include a cleaning device (not shown). After the cleaning device is divided by the thinning dividing device 520, and before the thinning etching device 530 is etched, the second main surface 12. May be washed.

Similarly, the thinning device 220 may further include a polishing device 540. The polishing apparatus 540 polishes the second main surface 12 divided by the thinning dividing apparatus 520 of the substrate to be processed 10 and smoothes the second main surface 12. The thinning device 220 may further include a cleaning device (not shown), and the cleaning device cleans the second main surface 12 after dividing by the thinning dividing device 520 and before polishing by the polishing device 540. May be.

The thinning device 220 may have only one of the thinning etching device 530 and the polishing device 540 or both. In the latter case, the thin plate etching apparatus 530 and the polishing apparatus 540 may process the substrate to be processed 10 in this order, for example.

Note that the thinning device 220 of the present modification simultaneously performs the division on the first scheduled division surface S1 and the division on the second scheduled division surface S2, but the division on the second scheduled division surface S2 is performed first. You may implement before the division | segmentation in 1 division | segmentation planned surface S1. In the latter case, the second modified layer M2 is formed such that the second crack CR2 reaches both the first main surface 11 and the second main surface 12. As a result, the bevel 19 can be removed over the entire thickness direction of the substrate 10 to be processed. Then, the division | segmentation in 1st division | segmentation planned surface S1 may be performed.

When the bevel 19 is removed over the entire thickness direction of the substrate 10 to be processed, the part to be removed is ring-shaped, and therefore the part to be removed may be divided into a plurality of arc-shaped pieces in the circumferential direction. . A plurality of arc-shaped divided pieces can be removed radially outward. A third modified layer is formed in advance on the third division planned surface, which is the boundary between the adjacent arc-shaped division pieces. The formation of the third modified layer is performed by the laser beam LB4, similarly to the formation of the first modified layer M1 and the second modified layer M2.

The second main surface 12 of the substrate to be processed 10 approaches the first main surface 11 of the substrate to be processed 10 by the division on the first planned division surface S1. As shown in FIG. 17, a part of the first modified layer M <b> 1 remains on the second main surface 12, and the remaining is the first defect layer 51. Since the substrate 10 to be processed has the first defect layer 51, it is transported in this order by the transport device 280 to the dividing device 240, the etching device 250, and the gettering layer forming device 260 in the same manner as in the above embodiment. ,It is processed. Note that the transfer device 280 is also used to transfer the substrate 10 to be processed between a plurality of devices constituting the thinning device 220.

This application claims priority based on Japanese Patent Application No. 2018-112272 filed with the Japan Patent Office on June 12, 2018. The entire contents of Japanese Patent Application No. 2018-112272 are incorporated herein by reference. .

DESCRIPTION OF SYMBOLS 1 Substrate processing system 10 Substrate 20 Support substrate 30 Superposition substrate 100 Loading / unloading station 200 Processing station 210 Peripheral part processing apparatus 220 Thin plate apparatus 230 Cleaning apparatus 240 Dividing apparatus 250 Etching apparatus 260 Gettering layer forming apparatus 261 Substrate holding part 262 Parallel movement mechanism part 265 Rotation movement mechanism part 270 Optical part 271 Scan mechanism 280 Conveying device 300 Control device 510 Laser processing device 520 Thin plate dividing device 530 Thin plate etching device 540 Polishing device

Claims

A thinning device for thinning the substrate to be processed;
A dividing device for dividing the thinned substrate to be processed into a plurality of chips;
An etching apparatus for etching both the thinned surface of the chip and the divided surface of the chip;
A gettering layer forming apparatus for forming a gettering layer in the chip at a predetermined depth from the thinned and etched surface of the chip or from the surface;
A transport device that transports the substrate to be processed to the thinning device, the dividing device, the etching device, and the gettering layer forming device;
A substrate processing system comprising: the thinning device, the dividing device, the etching device, the gettering layer forming device, and a control device that controls the transfer device.
The gettering layer forming apparatus includes a substrate holding unit that holds the substrate to be processed, and an optical unit that irradiates the substrate to be processed held by the substrate holding unit with a laser beam that forms the gettering layer. Have
The substrate processing system according to claim 1, wherein the optical unit includes a scanning mechanism that moves an irradiation point of the laser beam on the substrate to be processed.
The substrate processing system according to claim 2, wherein the gettering layer forming apparatus includes a rotation moving mechanism unit that rotates and moves the substrate holding unit.
The controller is
Control the formation of the gettering layer by moving the irradiation point two-dimensionally by the scanning mechanism in a state where the substrate holding unit is stopped.
Performing rotation control of the substrate holding unit to switch a region of the substrate to be processed held by the substrate holding unit to move the irradiation point two-dimensionally by the scanning mechanism. Item 4. The substrate processing system according to Item 3.
The substrate processing system according to any one of claims 2 to 4, wherein the gettering layer forming apparatus includes a translation mechanism that translates the substrate holder.
The controller is
Control the formation of the gettering layer by moving the irradiation point two-dimensionally by the scanning mechanism in a state where the substrate holding unit is stopped.
Performing a control of switching a region in which the irradiation point is moved two-dimensionally by the scanning mechanism of the substrate to be processed held by the substrate holding unit by moving the substrate holding unit in parallel. Item 6. The substrate processing system according to Item 5.
The control device rotates and moves the substrate holder, and reciprocally moves the laser beam in the radial direction of the substrate to be processed held by the substrate holder, thereby setting a circle set on the substrate to be processed. The substrate processing system according to claim 3, wherein the gettering layer is formed in a shaped region.
The control device controls to reduce the number of rotations of the substrate holding portion as the irradiation point of the laser beam is further away from the center of the substrate to be processed, and the irradiation point of the laser beam is further away from the center of the substrate to be processed. The substrate processing system according to claim 7, wherein at least one of the controls for slowing down the moving speed of the irradiation point is executed.
The controller is
A plurality of regions set concentrically on the substrate to be processed by rotating the substrate holder and reciprocating the laser beam in the radial direction of the substrate to be processed held by the substrate holder. In order to form the gettering layer in turn,
The control for switching a region for forming the gettering layer is performed by translating the substrate holder in the linear movement direction of the laser beam when forming the gettering layer. The substrate processing system as described.
10. The substrate processing system according to claim 1, wherein the thinning device includes a grinding device that grinds the substrate to be processed.
The thinning device is:
A laser processing device for forming a condensing point of a laser beam on a division planned surface in a thickness direction of the substrate to be processed, and forming a modified layer at the condensing point;
The substrate processing system according to any one of claims 1 to 10, further comprising a thinning dividing device that divides the substrate to be processed along the division plane.
12. The substrate processing system according to claim 11, wherein the thinning device includes a thinning etching device that etches a surface divided by the dividing device.
The substrate processing system according to claim 11 or 12, wherein the thinning device includes a polishing device for polishing a surface divided by the dividing device.
A step of thinning the substrate to be processed;
Dividing the thinned substrate to be processed into a plurality of chips;
Etching both surfaces of the thinned surface of the chip and the divided surface of the chip;
Forming a gettering layer on the thinned and etched surface of the chip or in the chip at a predetermined depth from the surface.
Irradiating a laser beam for forming the gettering layer on the substrate to be processed held by a substrate holding unit;
The substrate processing method according to claim 14, further comprising: moving an irradiation point of the laser beam on the substrate to be processed by a scanning mechanism provided in the middle of the path of the laser beam.
Forming the gettering layer by moving the irradiation point two-dimensionally by the scanning mechanism in a state where the substrate holding unit is stopped;
The method includes a step of switching a region in which the irradiation point is moved two-dimensionally by the scan mechanism of the substrate to be processed held by the substrate holding unit by rotating the substrate holding unit. 15. The substrate processing method according to 15.
Forming the gettering layer by moving the irradiation point two-dimensionally by the scanning mechanism in a state where the substrate holding unit is stopped;
And a step of switching an area in which the irradiation point is moved two-dimensionally by the scan mechanism of the substrate to be processed held by the substrate holding unit by moving the substrate holding unit in parallel. The substrate processing method according to 15 or 16.
While rotating the substrate holding part and reciprocating the laser beam in the radial direction of the substrate to be processed held by the substrate holding part, the circular region set in the substrate to be processed is The substrate processing method according to claim 15, wherein a gettering layer is formed.
The step of reducing the number of rotations of the substrate holder as the irradiation point of the laser beam is further away from the center of the substrate to be processed; and the irradiation point as the irradiation point of the laser beam is away from the center of the substrate to be processed. The substrate processing method according to claim 18, further comprising at least one step of slowing down the moving speed of the substrate.
A plurality of regions set concentrically on the substrate to be processed by rotating the substrate holder and reciprocating the laser beam in the radial direction of the substrate to be processed held by the substrate holder. Forming the gettering layer in turn,
The method includes: switching a region for forming the gettering layer by translating the substrate holder in a linear movement direction of the laser beam when the gettering layer is formed. Substrate processing method.