Substrate processing method, and substrate processing device

Abstract

A substrate processing method is provided, comprising: preparing a laminated substrate including a first substrate divided into a plurality of chips, a protective film that protects each chip in a state where the division is finished, a second substrate that supports the first substrate, and an adhesive film that bonds the protective film and the second substrate; reducing the adhesive strength of the adhesive film with a light beam that passes through the second substrate; and picking up the protective film and the chips with reduced adhesive strength from the adhesive film using a pickup unit.

Description

Technology Field

[0001] The present disclosure relates to a substrate processing method and a substrate processing apparatus. Background Technology

[0002] The semiconductor wafer splitting method described in Patent Document 1 comprises an integration process, a polishing process, a splitting process, and a pickup process. In the integration process, the surface of the semiconductor wafer is placed facing the upper surface of a support substrate that supports the semiconductor wafer, and the semiconductor wafer and the support substrate are integrated by interposing an adhesive. In the polishing process, the back side of the semiconductor wafer integrated with the support substrate is polished. In the splitting process, the semiconductor wafer integrated with the support substrate is split into individual semiconductor chips from the back side. In the pickup process, the semiconductor chips are picked up from the support substrate. Before pickup, an external stimulus, such as ultraviolet light, is applied to the adhesive, thereby reducing its adhesive strength. Prior art literature

[0003] Japanese Patent Publication No. 2004-207607 The problem to be solved

[0004] One aspect of the present disclosure provides a technology that can suppress the degradation of a chip device when a light that reduces adhesion is irradiated before pickup. means of solving the problem

[0005] A substrate processing method according to one aspect of the present disclosure is,

[0006] Preparing a laminated substrate comprising a first substrate divided into a plurality of chips, a protective film protecting each chip in a state where the division is completed, a second substrate supporting the first substrate, and an adhesive film bonding the protective film and the second substrate, and

[0007] Reducing the adhesive strength of the adhesive film with a light beam passing through the second substrate, and

[0008] Picking up the protective film and the chip, which have reduced adhesion to the adhesive film, from the adhesive film by a pickup unit.

[0009] has Effects of the invention

[0010] According to one aspect of the present disclosure, when a light that reduces adhesion is irradiated before pickup, the degradation of the chip device can be suppressed. Brief explanation of the drawing

[0011] FIG. 1 is a flowchart illustrating a substrate processing method according to one embodiment. Figure 2 (A) is a figure representing S101 of Figure 1, Figure 2 (B) is a figure representing S102 of Figure 1, and Figure 2 (C) is a figure representing S103 of Figure 1. Figure 3 (A) is a figure representing S104 of Figure 1, Figure 3 (B) is a figure representing S105 of Figure 1, and Figure 3 (C) is a figure representing S106 of Figure 1. FIG. 4 is a plan view showing an example of the first main surface of the first substrate before division. FIG. 5 is a plan view showing a substrate processing apparatus according to one embodiment. FIG. 6 is a flowchart showing a first example of a process performed prior to S101 of FIG. 1. Figure 7 (A) is a figure representing S201 of Figure 6, Figure 7 (B) is a figure representing S202 of Figure 6, Figure 7 (C) is a figure representing S203 of Figure 6, and Figure 7 (D) is a figure representing S204 of Figure 6. Figure 8 (A) is a figure representing S205 of Figure 6, Figure 8 (B) is a figure representing S206 of Figure 6, and Figure 8 (C) is a figure representing S207 of Figure 6. FIG. 9 is a flowchart showing a second example of a process performed prior to S101 of FIG. 1. Figure 10 (A) is a figure representing S305 of Figure 9, Figure 10 (B) is a figure representing S306 of Figure 9, Figure 10 (C) is a figure representing S307 of Figure 9, and Figure 10 (D) is a figure representing S308 of Figure 9. FIG. 11 is a flowchart showing a third example of a process performed prior to S101 of FIG. 1. Figure 12 is a figure showing S407 of Figure 11. FIG. 13 is a flowchart showing a fourth example of a process performed prior to S101 of FIG. 1. Figure 14 (A) is a figure representing S503 of Figure 13, Figure 14 (B) is a figure representing S504 of Figure 13, and Figure 14 (C) is a figure representing S505 of Figure 13. Specific details for implementing the invention

[0012] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In addition, in each drawing, the same or corresponding components are given the same reference numerals, and descriptions may be omitted. In this specification, 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.

[0013] As shown in FIG. 1, the substrate processing method comprises preparing a laminated substrate (S101), reducing adhesion (S102), picking up a chip (S103), removing a protective film (S104), activating the chip surface (S105), and bonding the chip to a third substrate (S106). Additionally, the substrate processing method may include processing other than that shown in FIG. 1. Processing performed before the preparation of the laminated substrate (S101) will be described later.

[0014] In the preparation of the laminated substrate (S101), as shown in (A) of FIG. 2, a laminated substrate (50) comprising a first substrate (10), a protective film (20), a second substrate (30), and an adhesive film (40) is prepared. The preparation of the laminated substrate (50) includes, for example, holding the laminated substrate (50) with a first support member (110). The first support member (110) holds the laminated substrate (50) from below by orienting the second main surface (12) of the first substrate (10) upward. The first substrate (10) includes a first main surface (11) and a second main surface (12) that is in the opposite direction to the first main surface (11).

[0015] The first substrate (10) includes a lower substrate (13), which is a semiconductor substrate such as a silicon wafer or a glass substrate, and a device (14) formed on the surface of the lower substrate (13). In S101, the first substrate (10) is in a state where it has been divided into a plurality of chips (15). Each of the plurality of chips (15) includes a device (14). In addition, the number of chips (15) is not particularly limited. In FIG. 2, fewer chips (15) than in FIG. 4 are shown due to space constraints.

[0016] As shown in FIG. 4, the first main surface (11) of the first substrate (10) before division is divided into multiple regions by multiple intersecting division lines (16). In each of the multiple regions, a device (14), such as a semiconductor element, circuit, or terminal, is formed in advance. The first substrate (10) is divided by multiple division lines (16) and divided into multiple chips (15).

[0017] As shown in FIG. 2, the protective film (20) protects the first main surface (11) of the first substrate (10) and protects the device (14) of the first main surface (11). The protective film (20) is formed, for example, from a resin. In S101, the protective film (20) is in a state where it has been divided at the same location as the first substrate (10) and has been divided for each chip (15). The divided surface of the protective film (20) and the divided surface of the chip (15) may be located on the same plane.

[0018] The second substrate (30) supports the first substrate (10). The second substrate (30) supports a plurality of chips (15) flatly to suppress bending of the chips (15). The thickness of the second substrate (30) may be thicker than the thickness of the chips (15). In addition, the diameter of the second substrate (30) may be greater than or equal to the diameter of the first substrate (10). For example, a semiconductor substrate or a glass substrate is used as the second substrate (30).

[0019] The adhesive film (40) adheres the protective film (20) and the second substrate (30). The adhesive film (40) is formed, for example, from a resin. The adhesive film (40) is not particularly limited as long as it reduces the adhesive strength by light rays such as infrared rays that pass through the second substrate (30), but, for example, it may include microcapsules that expand or foam upon irradiation with light rays, or foaming agents that foam upon irradiation with light rays. Additionally, the adhesive film (40) may sublimate upon irradiation with light rays.

[0020] In the reduction of adhesive strength (S102), as shown in (B) of FIG. 2, the adhesive strength of the adhesive film (40) is reduced by a light beam (L1) that passes through the second substrate (30). The light beam (L1) is irradiated from the second substrate (30) to the adhesive film (40). Compared to the case where the light beam (L1) is irradiated from the first substrate (10) to the adhesive film (40), the intensity of the light beam (L1) reaching the device (14) of the first substrate (10) is lower, so the deterioration of the device (14) can be suppressed. The reduction of adhesive strength may be performed on the entire adhesive film (40) at once, or it may be performed on each chip (15).

[0021] The first holding member (110) can be moved in the X-axis direction and the Y-axis direction to change the irradiation position of the light beam (L1) in the adhesive film (40). Additionally, as long as the irradiation position of the light beam (L1) in the adhesive film (40) can be changed, the irradiator (120) that irradiates the light beam (L1) may also be moved. Furthermore, if the irradiator (120) includes a galvanometer scanner, etc., neither the first holding member (110) nor the irradiator (120) needs to be moved.

[0022] The intensity of the light beam (L1) is reduced by contact with the adhesive film (40). This is because most of the energy of the light beam (L1) is used to reduce the adhesive strength of the adhesive film (40). However, some of the light beam (L1) is not absorbed by the adhesive film (40) and can pass through the adhesive film (40).

[0023] Accordingly, in this embodiment, as shown in (B) of FIG. 2, a protective film (20) exists between the adhesive film (40) and the first substrate (10). When a light ray (L1) passes through the protective film (20), a portion of the light ray (L1) is absorbed by the protective film (20), and the intensity of the light ray (L1) is further reduced. As a result, the intensity of the light ray (L1) reaching the device (14) of the first substrate (10) can be reduced, thereby suppressing the deterioration of the device (14). The material of the protective film (20) is appropriately selected according to the wavelength of the light ray (L1).

[0024] When the second substrate (30) is a silicon wafer, for example, infrared light is used as the light beam (L1) that passes through the silicon wafer, and the wavelength of the light beam (L1) is, for example, 700 nm or more and 1 mm or less. The light beam (L1) may be a laser beam. The oscillation method of the laser beam may be either a continuous oscillation type or a pulse oscillation type. As a light source for the laser beam, a semiconductor laser, a YAG laser, or a carbon dioxide laser is used.

[0025] When the light ray (L1) also passes through the first retainer (110), the material of the first retainer (110) may be glass. Additionally, the first retainer (110) may be configured so that the light ray (L1) does not reach it, for example, it may only retain the outer periphery of the laminated substrate (50). In this case, the material of the first retainer (110) is not limited to glass, but may be metal or ceramic.

[0026] In the pickup (S103) of the chip (15), as shown in (C) of FIG. 2, the protective film (20) with reduced adhesion to the adhesive film (40) and the chip (15) are picked up from the adhesive film (40) by the pickup unit (130). The pickup unit (130) adsorbs the chip (15) from above. The size of the adsorption surface of the pickup unit (130) is the same as or slightly larger than the size of the upper surface of the chip (15). The pickup unit (130) is, for example, a collet.

[0027] The chip (15) is supported by a hard second substrate (30) until it is picked up by the pickup unit (130). Compared to the case where the chip (15) is supported by a soft tape, such as so-called dicing tape, instead of the second substrate (30), there is almost no change in the position of the chip (15), making it easy to align the position of the chip (15) with the pickup unit (130).

[0028] In the removal (S104) of the protective film (20), as shown in (A) of FIG. 3, the protective film (20) is removed by immersing it in a liquid (L2) that dissolves the protective film (20) while holding the chip (15) by the pickup unit (130). Since the protective film (20) is dissolved and removed, particles attached to the protective film (20) can also be removed.

[0029] The liquid (L2) is appropriately selected according to the material of the protective film (20), and may be, for example, an organic solvent. The liquid (L2) is stored in advance in a tank of the storage section (140). The storage section (140) is, for example, a container open upward. When the protective film (20) is immersed in the liquid (L2), the pickup section (130) does not need to be immersed in the liquid (L2). This can suppress the deterioration of the pickup section (130).

[0030] The pickup unit (130) continues to hold the chip (15) from above with the protective film (20) facing downward, after the pickup of the chip (15) (S103) and until the removal (S104) of the protective film (20). When the protective film (20) is immersed in the liquid (L2), the pickup unit (130) does not need to be immersed in the liquid (L2). Additionally, since the chip (15) is not transferred between the pickup unit (130) and another pickup unit, the chip (15) can be prevented from breaking during transfer.

[0031] In the activation of the chip surface (S105), as shown in (B) of FIG. 3, the surface (15a) from which the protective film (20) of the chip (15) has been removed is activated while the chip (15) is held by the pickup unit (130). The surface (15a) of the chip (15) is the first main surface (11) of the first substrate (10), and a device (14) exists on the surface (15a) of the chip (15). Since the surface of the device (14) is activated, it can be bonded by facing the main surface (61) on which the device (64) of the third substrate (60) is formed, which will be described later.

[0032] The activation unit (150) activates the surface (15a) of the chip (15). The activation unit (150) activates the surface (15a) of the chip (15) by the generated plasma, for example, as a plasma generator. The plasma may be atmospheric pressure plasma or vacuum plasma, and may be atmospheric pressure plasma that does not require a vacuum container.

[0033] Plasma is generated by exciting, for example, oxygen gas or nitrogen gas. Plasma breaks the chemical bonds of molecules (e.g., SiO2) on the surface (15a), for example, to form functional groups or unbonded water. The activating part (150) may hydrophilize the surface (15a) of the chip (15) by treating it with plasma and then treating it with pure water.

[0034] The pickup unit (130) continues to hold the chip (15) from above with the protective film (20) facing downward, after the pickup (S103) of the chip (15) and until at least the activation (S105) of the chip surface. Since the chip (15) is not transferred between the pickup unit (130) and another pickup unit, it is possible to prevent the chip (15) from breaking during transfer.

[0035] In the bonding (S106) between the chip (15) and the third substrate (60), as shown in (C) of FIG. 3, the chip (15) is held by the pickup unit (130), and the activated surface (15a) of the chip (15) is brought to face the main surface (61) on which the device (64) of the third substrate (60) is formed, thereby bonding them. The device (14) on the surface (15a) of the chip (15) and the device (64) on the main surface (61) of the third substrate (60) are bonded, and the third substrate (60) to which the chip (15) is attached is obtained. The third substrate (60) to which the chip (15) is attached may be a so-called COW (Chip On Wafer).

[0036] The second holding member (160) holds the third substrate (60) from below by having the main surface (61) of the third substrate (60) face upward. Meanwhile, the pickup unit (130) holds the chip (15) from above by having the activated surface (15a) of the chip (15) face downward. After picking up the chip (15) (S103), the pickup unit (130) continues to hold the chip (15) from above with the surface (15a) of the chip (15) facing downward until the bonding (S106) between the chip (15) and the third substrate (60). Since the chip (15) is not transferred between the pickup unit (130) and another pickup unit, it is possible to prevent the chip (15) from breaking during transfer.

[0037] The preparation of a laminated substrate (S101), reduction of adhesion (S102), pickup of a chip (S103), removal of a protective film (S104), activation of the chip surface (S105), and bonding of the chip and a third substrate (S106), as shown in FIG. 1, are carried out in a substrate processing device (100) as shown in FIG. 5, for example.

[0038] As shown in FIG. 5, the substrate processing device (100) is equipped with an incoming / outgoing station (170), a processing station (180), and a control device (190). The incoming / outgoing station (170) and the processing station (180) are arranged in this order from the X-axis direction side to the X-axis direction side.

[0039] The incoming / outgoing station (170) has an incoming / outgoing block (171) and a return block (172). The return block (172) is positioned next to the incoming / outgoing block (171), for example, on the X-axis direction side of the incoming / outgoing block (171). Additionally, the return block (172) is positioned next to the processing station (180), for example, on the X-axis direction side of the processing station (180).

[0040] The incoming / outgoing block (171) includes a plurality of placement sections (173) arranged in a row in the Y-axis direction. A cassette is placed in each of the plurality of placement sections (173). The first cassette (C1) accommodates a laminated substrate (50), the second cassette (C2) accommodates a third substrate (60), the third cassette (C3) accommodates a third substrate (60) to which a chip (15) is attached, and the fourth cassette (C4) accommodates the remaining second substrate (30) after picking up the chip (15) and the protective film (20) from the laminated substrate (50). Additionally, the number of placement sections (173) is not particularly limited. Likewise, the number of cassettes is not particularly limited.

[0041] A conveying device (174) is provided inside the conveying block (172). The conveying device (174) has a holding portion that holds a laminated substrate (50) and a third substrate (60), etc. The holding portion is capable of moving in the horizontal direction (both directions of the X-axis and Y-axis) and the vertical direction, and rotating around the vertical axis. The conveying device (174) takes out the laminated substrate (50) from the first cassette (C1) and places it on the first holding stand (110). Additionally, the conveying device (174) takes out the third substrate (60) from the second cassette (C2) and places it on the second holding stand (160). Additionally, the conveying device (174) receives the third substrate (60) with the chip (15) attached from the second holding stand (160) and stores it in the third cassette (C3). Additionally, the return device (174) receives the remaining second substrate (30) from the first holding stand (110) after picking up the chip (15) and the protective film (20) from the laminated substrate (50), and stores it in the fourth cassette (C4).

[0042] The processing station (180) has a first holding unit (110), an irradiator (120), a pickup unit (130), a moving unit (135), a storage unit (140), an activation unit (150), and a second holding unit (160). The first holding unit (110), the storage unit (140), the activation unit (150), and the second holding unit (160) are arranged in this order from the Y-axis direction positive side to the Y-axis direction negative side. The irradiator (120) is provided below the first holding unit (110). The pickup unit (130) is capable of moving in the horizontal direction (both directions of the X-axis and Y-axis) and the vertical direction, as well as rotating around the vertical axis. The number of pickup units (130) is one in FIG. 4, but may be multiple. The moving unit (135) moves the pickup unit (130) so as to move the chip (15) held in the pickup unit (130) from the first holding unit (110) through the storage unit (140) and the activation unit (150) to the second holding unit (160).

[0043] The control device (190) is, for example, a computer and, as shown in FIG. 5, is equipped with a CPU (Central Processing Unit) (191) and a storage medium (192), such as memory. A program for controlling various processes executed in the substrate processing device (100) is stored in the storage medium (192). The control device (190) controls the operation of the substrate processing device (100) by executing the program stored in the storage medium (192) on the CPU (191). Additionally, the control device (190) is equipped with an input interface (193) and an output interface (194). The control device (190) receives a signal from the outside through the input interface (193) and transmits a signal to the outside through the output interface (194).

[0044] The above program is stored, for example, in a computer-readable storage medium and installed from the storage medium to the storage medium (192) of the control device (190). Examples of computer-readable storage media include a hard disk (HD), a flexible disk (FD), a compact disk (CD), a magnetic optical disk (MO), a memory card, etc. Additionally, the program may be downloaded from a server via the Internet and installed to the storage medium (192) of the control device (190).

[0045] Next, with reference to FIGS. 6, 7, and 8, a first example of a process performed prior to S101 of FIG. 1 will be described.

[0046] As shown in FIG. 6, the substrate processing method comprises preparing a first substrate (10) (S201), forming a protective film (20) (S202), forming a first groove (71) (S203), bonding the protective film (20) and the second substrate (30) (S204), thinning the first substrate (10) (S205), forming a mask (72) (S206), and forming a second groove (73) (S207).

[0047] In the preparation (S201) of the first substrate (10), for example, the first substrate (10) is held in a holding plate not shown. The first substrate (10) is held from below with the first main surface (11) facing upward, as shown in (A) of FIG. 7. The device (14) is formed on the first main surface (11).

[0048] In the formation of the protective film (20) (S202), as shown in (B) of FIG. 7, the protective film (20) is formed on the first main surface (11) of the first substrate (10). The protective film (20) is formed, for example, by a spin coating method. A nozzle (201) discharges a coating liquid (L3) from above onto the rotating first substrate (10) to form a liquid film of the coating liquid (L3). When the liquid film is dried, the protective film (20) is obtained. Furthermore, the method of applying the coating liquid (L3) is not limited to the spin coating method.

[0049] As described above, the protective film (20) absorbs light rays (L1) that pass through the adhesive film (40) during the reduction of adhesive strength (S102), thereby suppressing the deterioration of the device (14). In addition, the protective film (20) also serves to suppress debris generated during the formation (S203) of the first groove (71) described later from adhering to the device (14).

[0050] In the formation of the first groove (71) (S203), as shown in (C) of FIG. 7, a first groove (71) deeper than the device (14) is formed on the planned division line of the surface of the protective film (20). The first groove (71) extends to the lower substrate (13). The planned division line of the surface of the protective film (20) coincides with the planned division line (16) of the first main surface (11) of the first substrate (10) when viewed in a plane. The position of the planned division line (16) is detected by capturing an image of the first main surface (11) using, for example, an infrared camera, and processing the captured image. The formation position of the first groove (71) is determined by the position of the detected planned division line (16).

[0051] The first groove (71) may be formed by cutting with a blade, but in this embodiment, it is formed by ablation processing with a laser beam (L4). Ablation processing is effective when the device (14) is soft, such as when the device (14) contains, for example, a porous Low-k material. To prevent overheating of the device (14), a single pulse laser may be used as the light source for the laser beam (L4).

[0052] The wavelength of the laser beam (L4) may be different from the wavelength of the light beam (L1). This is because the roles of the laser beam (L4) and the light beam (L1) are different. As described above, the light beam (L1) is used to reduce the adhesive strength of the adhesive film (40). The wavelength of the laser beam (L4) may be shorter than the wavelength of the light beam (L1), and for example, may be 600 nm or less.

[0053] The formation of the first groove (71) (S203) is performed after the formation of the protective film (20) (S202) and before the adhesion (S204) between the protective film (20) and the second substrate (30). Since the protective film (20) is formed before the formation of the first groove (71), debris generated during the formation of the first groove (71) can be prevented from adhering to the device (14).

[0054] In the bonding (S204) between the protective film (20) and the second substrate (30), as shown in (D) of FIG. 7, the protective film (20) and the second substrate (30) are bonded with an adhesive film (40). Since the first substrate (10) and the second substrate (30) are bonded with the adhesive film (40), the second substrate (30) can support the first substrate (10).

[0055] The adhesive film (40) is formed by applying an adhesive to the bonding surface of the second substrate (30), and subsequently, the protective film (20) is placed thereon. This prevents the first groove (71) on the surface of the protective film (20) from being filled with adhesive. Additionally, the adhesive film (40) may be supplied in the form of a sheet, in which case the adhesive film (40) may be attached first to either the protective film (20) or the second substrate (30).

[0056] Thinning (S205) of the first substrate (10) is performed after adhesion (S204) between the protective film (20) and the second substrate (30). Thinning of the first substrate (10) includes grinding the second main surface (12) of the first substrate (10) as shown in (A) of FIG. 8. Polishing may be performed further after grinding. Since the first substrate (10) is processed while the first substrate (10) is reinforced with the second substrate (30), cracking of the first substrate (10) can be suppressed. Grinding of the first substrate (10) is performed by a grinding stone (202). The grinding stone (202) descends while rotating and grinds the upper surface (second main surface (12)) of the rotating first substrate (10). Polishing is performed in the same way. On the second main surface (12) after peeling, the first groove (71) is not exposed.

[0057] The formation (S206) of the mask (72) is performed after the thinning (S205) of the first substrate (10). The mask (72) is formed by a photolithography method or the like, and has an opening (72a) at the planned division line of the second main surface (12) of the first substrate (10), as shown in (B) of FIG. 8. The planned division line of the second main surface (12) and the planned division line (16) of the first main surface (11) coincide when viewed from a plane. The position of the planned division line (16) is detected by capturing an image of the first main surface (11) using, for example, an infrared camera, and processing the captured image. The position of the opening (72a) of the mask (72) is determined by the position of the detected planned division line (16). The material of the mask (72) is not particularly limited as long as it can withstand the etching described later.

[0058] In the formation of the second groove (73) (S207), as shown in (C) of FIG. 8, the second main surface (12) of the first substrate (10) is etched through the opening (72a) of the mask (72), and the second groove (73) leading to the first groove (71) is formed to divide the first substrate (10) into a plurality of chips (15). The plurality of chips (15) are flatly supported by the second substrate (30). The etching may be either wet etching or dry etching, and may be dry etching with excellent anisotropy, and may be, for example, plasma etching.

[0059] Since the first substrate (10) is divided into a plurality of chips (15) by etching, distortion and scratches on the chips (15) can be suppressed when the chips (15) are divided, and also, the generation of particles can be suppressed when the chips (15) are divided. In addition, when the second groove (73) is connected to the first groove (71), the side (71a) of the first groove (71) is also etched, so distortion, scratches, and particles that occurred when the first groove (71) was formed can also be removed.

[0060] The timing at which the mask (72) is removed may be at any time after the formation of the second groove (73) (S207), before the pickup (S103) of the chip (15), or after the bonding (S106) of the chip (15) and the third substrate (60). In the latter case, the pickup unit (130) holds the chip (15) from above through the mask (72).

[0061] Next, with reference to FIGS. 9 and FIGS. 10, a second example of a process performed prior to S101 of FIG. 1 will be described.

[0062] As shown in FIG. 9, the substrate processing method comprises preparing a first substrate (10) (S301), forming a protective film (20) (S302), forming a primary groove (S303), etching the side of the primary groove (S304), forming a secondary groove (75) (S305), bonding the protective film (20) and the second substrate (30) (S306), thinning the first substrate (10) (S307), and cleaning and etching (S308).

[0063] The preparation of the first substrate (10) (S301), the formation of the protective film (20) (S302), and the formation of the primary groove (S303) are performed in the same manner as S201, S202, and S203 shown in FIG. 6, so the description is omitted. Also, the primary groove obtained in S303 is the same as the first groove (71) shown in (C) of FIG. 7, so the illustration is omitted.

[0064] In the side etching (S304) of the primary groove, the side of the primary groove is etched. The etching may be either wet etching or dry etching, and may be dry etching that can evenly etch the side of the primary groove in the depth direction, or, for example, plasma etching. This removes distortions, scratches, and particles that occurred during the formation of the primary groove.

[0065] In the formation of the secondary groove (75) (S305), as shown in (A) of FIG. 10, the bottom surface of the primary groove is cut with a blade (301) to extend the primary groove in the depth direction, thereby forming the secondary groove (75). The depth of the secondary groove (75) is a depth that reaches the second main surface (12) of the first substrate (10) after thinning (S307) described later.

[0066] The formation of the secondary groove (75) (S305) is performed after the formation of the primary groove (S303), and the primary groove is formed by ablation processing using a laser beam. As described above, ablation processing is effective when the device (14) is soft, such as when the device (14) includes, for example, a porous Low-k material.

[0067] The depth of the primary groove is deeper than the depth of the device (14), and the primary groove extends to the lower substrate (13). Since the primary groove is formed in advance, cutting of the device (14) by the blade (301) can be suppressed, thereby suppressing the occurrence of warping and scratches on the device (14).

[0068] Additionally, depending on the structure of the device (14), ablation processing by a laser beam may not be performed, and only cutting processing by a blade (301) may be performed.

[0069] In the bonding (S306) of the protective film (20) and the second substrate (30), as shown in (B) of FIG. 10, the protective film (20) and the second substrate (30) are bonded with an adhesive film (40). Since the first substrate (10) and the second substrate (30) are bonded with the adhesive film (40), the second substrate (30) can support the first substrate (10).

[0070] The thinning (S307) of the first substrate (10) is performed after the adhesion (S306) between the protective film (20) and the second substrate (30). The thinning of the first substrate (10) includes grinding the second main surface (12) of the first substrate (10), as shown in (C) of FIG. 10. The grinding is performed by a grinding stone (302). After grinding, polishing may be further performed. By the thinning (S307), a secondary groove (75) is exposed on the second main surface (12) of the first substrate (10), and the first substrate (10) is divided into a plurality of chips (15). The plurality of chips (15) are flatly supported by the second substrate (30).

[0071] In cleaning and etching (S308), as shown in (D) of FIG. 10, the secondary groove (75) is cleaned and the side (75a) of the secondary groove (75) is etched. By cleaning the secondary groove (75), grinding debris generated during thinning of the first substrate (10) and cutting debris generated during the formation of the secondary groove (75) can be removed. Additionally, by etching the side (75a) of the secondary groove (75), warping and scratches generated during the formation of the secondary groove (75) can be removed.

[0072] Cleaning of the secondary groove (75) is, for example, scrub cleaning, spin cleaning, or spray cleaning. The nozzle (303) discharges a cleaning liquid (L5) from above relative to the laminated substrate (50). Not only the upper surface of the laminated substrate (50), but also the lower surface of the laminated substrate (50) may be cleaned simultaneously. In scrub cleaning, the surface of the laminated substrate (50) is scrubbed and washed with a brush or sponge not shown.

[0073] Cleaning of the secondary groove (75) and etching of the side (75a) of the secondary groove (75) may be performed individually or simultaneously. In the latter case, wet etching is performed. On the other hand, in the former case, the etching may be either wet etching or dry etching.

[0074] Next, with reference to FIGS. 11 and FIGS. 12, a third example of a process performed prior to S101 of FIG. 1 will be described.

[0075] As shown in FIG. 11, the substrate processing method comprises preparing a first substrate (10) (S401), forming a protective film (20) (S402), forming a first groove (71) (S403), lateral etching of the first groove (71) (S404), bonding of the protective film (20) and the second substrate (30) (S405), thinning of the first substrate (10) (S406), forming a second groove (73) (S407), and cleaning and etching (S408).

[0076] The preparation of the first substrate (10) (S401), the formation of the protective film (20) (S402), the formation of the first groove (71) (S403), and the side etching of the first groove (71) (S404) are performed in the same manner as S301, S302, S303, and S304 shown in FIG. 9, so the description is omitted.

[0077] Additionally, side etching (S404) of the first groove (71) is performed after the formation of the first groove (71) (S403) and before the bonding (S405) of the protective film (20) and the second substrate (30). This can remove warping, scratches, and particles that occurred during the formation of the first groove (71).

[0078] The bonding (S405) between the protective film (20) and the second substrate (30) is performed in the same manner as S204 shown in FIG. 6, so the description is omitted. The laminated substrate (50) obtained in S405 is the same as the laminated substrate (50) shown in (D) of FIG. 7, except that the side (71a) of the first groove (71) is in a state where etching is finished, so the illustration is omitted.

[0079] In addition, the thinning (S406) of the first substrate (10) is performed in the same manner as S205 shown in FIG. 6, so the description is omitted. The laminated substrate (50) obtained in S406 is identical to the laminated substrate (50) shown in FIG. 8 (A), except that the side (71a) of the first groove (71) is in a state where etching is finished, so the illustration is omitted.

[0080] The formation (S407) of the second groove (73) is performed after the thinning (S406) of the first substrate (10). Unlike the first example shown in FIGS. 6, 7 and 8, the second groove (73) is formed by cutting with a blade (401) as shown in FIG. 12, instead of etching. The blade (401) grinds the planned division line of the second main surface (12) of the first substrate (10). The second groove (73) leads to the first groove (71), and the first substrate (10) is divided into a plurality of chips (15). Since the first groove (71) is formed in advance, the blade (401) does not cut the device (14), so the occurrence of warping and scratches on the device (14) can be suppressed.

[0081] Cleaning and etching (S408) are performed in the same manner as S308 shown in FIG. 9. In S408, the second groove (73) is cleaned, and the side (73a) of the second groove (73) is etched. By cleaning the second groove (73), grinding debris generated during thinning of the first substrate (10) and cutting debris generated during the formation of the second groove (73) can be removed. Additionally, by etching the side (73a) of the second groove (73), warping and scratches generated during the formation of the second groove (73) can be removed.

[0082] Cleaning of the second groove (73) is performed in the same manner as cleaning of the secondary groove (75) ((D) of FIG. 10). Additionally, etching of the side (73a) of the second groove (73) is performed in the same manner as etching of the side (75a) of the secondary groove (75). Since the second groove (73) and the secondary groove (75) are both formed by cutting with a blade, the same post-processing is performed.

[0083] Next, with reference to FIGS. 13 and FIGS. 14, a fourth example of a process performed prior to S101 of FIG. 1 will be described.

[0084] As shown in FIG. 13, the substrate processing method comprises preparing a first substrate (10) (S501), forming a protective film (20) (S502), bonding the protective film (20) and the second substrate (30) (S503), thinning the first substrate (10) (S504), forming a groove (76) (S505), and cleaning and etching (S506).

[0085] The preparation (S501) of the first substrate (10) and the formation (S502) of the protective film (20) are performed in the same way as S201 and S202 shown in FIG. 6, so the description is omitted.

[0086] The bonding (S503) between the protective film (20) and the second substrate (30) is performed in the same manner as S204 shown in FIG. 6, except that the groove processing is not performed on the first substrate (10). The laminated substrate (50) obtained in S503 is shown in (A) of FIG. 14.

[0087] The thinning (S504) of the first substrate (10) is performed in the same manner as S205 shown in FIG. 6, except that the first substrate (10) is not grooved. The laminated substrate (50) obtained in S504 is shown in (B) of FIG. 14.

[0088] The formation of the groove (76) (S505) is performed after the thinning (S504) of the first substrate (10). The groove (76) is formed on the planned division line of the second main surface (12) of the first substrate (10), penetrates the first substrate (10) and the protective film (20), and reaches the adhesive film (40). By forming the groove (76), the first substrate (10) is divided into a plurality of chips (15), and the protective film (20) is also divided for each chip (15).

[0089] The groove (76) may be formed by cutting with a blade, but in this embodiment, it is formed by ablation processing with a laser beam (L6). Ablation processing is effective when the device (14) is soft, such as when the device (14) contains, for example, a porous Low-k material.

[0090] Since the groove (76) penetrates the first substrate (10) and the protective film (20), the depth of the groove (76) is deeper than the depth of the first groove (71) shown in (C) of FIG. 7, and the intensity of the laser beam (L6) is higher than the intensity of the laser beam (L4) shown in (C) of FIG. 7. Therefore, warping and scratches are likely to occur. Accordingly, after the formation of the groove (76) (S505), cleaning and etching (S506) are performed.

[0092] *Cleaning and etching (S506) are performed in the same manner as S308 shown in FIG. 9. In S408, the groove (76) is cleaned, and the side (76a) of the groove (76) is etched. By cleaning the groove (76), grinding debris generated during thinning of the first substrate (10) and debris generated during the formation of the groove (76) can be removed. Additionally, by etching the side (76a) of the groove (76), warping and scratches generated during the formation of the groove (76) can be removed.

[0093] Additionally, depending on the structure of the device (14), the groove (76) may be formed by cutting. In this case, cleaning and etching (S506) may be performed after the formation of the groove (76) (S505). In this case, the same effect is obtained.

[0094] Although a substrate processing method and a substrate processing apparatus according to the present disclosure have been described above, the present disclosure is not limited to the above embodiments. Various changes, modifications, substitutions, additions, deletions, and combinations are possible within the scope described in the claims. These also naturally fall within the technical scope of the present disclosure.

[0095] In S205 of FIG. 6, S307 of FIG. 9, S406 of FIG. 11, and S504 of FIG. 13, the second main surface (12) of the first substrate (10) is ground to thin the first substrate (10), but the technology of the present disclosure is not limited thereto. In thinning the first substrate (10), a portion of the first substrate (10) may be removed from the second main surface (12) side so that the second main surface (12) is brought close to the first main surface (11). For example, a laser beam may be focused and irradiated onto a dividing surface that divides the first substrate (10) in the direction of plate thickness to form a plurality of modified layers spaced apart on the dividing surface, and then the first substrate (10) may be cut along the dividing surface starting from the modified layer to remove a portion of the first substrate (10).

[0096] This application claims priority based on Patent Application No. 2019-143300 filed with the Japan Patent Office on August 2, 2019, and incorporates all contents of Patent Application No. 2019-143300 into this application. Explanation of the symbols

[0097] 10: First substrate 11: First principal surface 12: Second main surface 14 : Device 15 : Chip 20: Shield 30 : Second substrate 40 : Adhesive film 50 : Laminated substrate 60 : 3rd substrate 61 : Main surface 64 : Device 100 : Substrate processing device 110: 1st Maintenance Unit 120 : Investigator 130 : Pickup unit 140 : Reservoir 150 : Activation part 160 : 2nd Maintenance Unit

Claims

Claim 1 A substrate processing method comprising: preparing a laminated substrate including a first substrate divided into a plurality of chips, a protective film protecting each chip in a state where the division is finished, a second substrate supporting the first substrate, and an adhesive film bonding the protective film and the second substrate; reducing the adhesive strength of the adhesive film with a light beam passing through the second substrate; picking up the protective film and the chip, with reduced adhesive strength with the adhesive film, from the adhesive film by a pickup unit; removing the protective film while holding the chip from above by the pickup unit until the protective film is removed; activating the surface of the chip from which the protective film has been removed while holding the chip by the pickup unit; and bonding the activated surface of the chip while holding the chip by the pickup unit by bringing it to face the main surface on which a device is formed on a third substrate. Claim 2 A substrate processing method according to claim 1, wherein, while holding the chip by the pickup unit, the activated surface of the chip is hydrophilized by treating it with pure water, and then faces the main surface on which the device of the third substrate is formed and bonds them. Claim 3 A substrate processing device comprising: a first holding member for holding a laminated substrate including a first substrate divided into a plurality of chips, a protective film protecting each chip in a state where the division is finished, a second substrate supporting the first substrate, and an adhesive film bonding the protective film and the second substrate; an irradiator that irradiates the second substrate with a light beam that penetrates the second substrate and reduces the adhesive strength of the adhesive film; a pickup unit for picking up the protective film and the chip that have reduced the adhesive strength with the adhesive film; a removal unit for removing the protective film with a liquid; a moving unit for moving the pickup unit to move the chip held by the pickup unit from the first holding member to the removal unit; an activating unit for activating the surface of the chip from which the protective film has been removed; and a second holding member for holding a third substrate that is bonded to the activated surface of the chip, wherein the moving unit moves the pickup unit to move the chip held by the pickup unit from the first holding member through the removal unit and the activation unit to the second holding member. Claim 4 In claim 3, the activation unit is a substrate processing device that hydrophilizes the surface of the activated chip.

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