TWI767022B - Substrate processing method and substrate processing system - Google Patents

Abstract

An object of the invention is to provide a substrate processing method capable of improving the processing stability of a semiconductor device.

The substrate processing method comprises: a support substrate adhesion step of adhering a support substrate to a first main surface of a substrate on the side on which a device layer is formed, a dicing step of performing stealth dicing of the substrate from a second main surface on the opposite side from the first main surface to which the support substrate was adhered in the support substrate adhesion step, and a thinning step of reducing the thickness of the substrate by grinding the second main surface of the substrate that was subjected to stealth dicing in the dicing step.

Description

Substrate processing method and substrate processing system

The present invention relates to a substrate processing method.

In recent years, in order to meet the demand for miniaturization and weight reduction of semiconductor devices, after forming elements, circuits, terminals, etc. on the first main surface of a substrate such as a semiconductor wafer, the second main surface opposite to the first main surface of the substrate is polished. The two main surfaces make the substrate thin. When the substrate is thinned, the first main surface of the substrate is protected with a protective tape. Generally, after thinning the substrate, the substrate is diced to divide the substrate into many semiconductor devices (see, for example, Patent Document 1).

[Prior Art Literature]

[Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2011-91240

In addition, as a dicing method of the substrate, stealth dicing (STEALTH DICING: SD) in which laser light is used to perform laser processing only on the inside of the substrate is known. In the manufacturing process of semiconductor devices, when the substrate is thinned after stealth dicing, if the second main surface is ground in a state where the protective tape is adhered to the first main surface as conventionally, the protection of each wafer is maintained. Since the rigidity of the belt is low, there is a possibility that the relative positions of the wafers may fluctuate, resulting in a lack of processing stability.

An object of the present disclosure is to provide a substrate processing method that can improve the processing stability of a semiconductor device.

A substrate processing method according to an aspect of an embodiment of the present invention includes: a step of attaching a support substrate to the first main surface on the device layer side where the substrate is formed; Next, stealth dicing of the substrate is performed on the second main surface opposite to the first main surface of the support substrate; and a thinning step is to grind the second main surface of the substrate after stealth dicing by the dicing step to The aforementioned substrate is thinned.

According to the present disclosure, a substrate processing method that can improve the processing stability of a semiconductor device can be provided.

1: Substrate processing system

10: Substrate

11: The first main surface

12: Second main surface

13: Wafer

14: Device layer

14a: bump

15: DAF (Die Attach Film)

16: Modified layer

20: Move in and out of the station

21: Mounting table

22: Loading plate

25, 31: Transfer area

26, 32: conveying road

27, 33: Conveying device

30: Processing Station

35: Transition Department

40: Support substrate bonding part

41: Support substrate

42: Next layer

51: Adhesive tape

52: Installation part

53: The remainder

59: Frame

90: Controls

91:CPU

92: Recording Media

93: Input interface

94: Output interface

100: Cutting part

110, 311, 410: substrate holding part

120: Substrate Processing Department

121, 421: Laser oscillator

122, 422: Optical system

130, 430, 550: Mobile Mechanism Department

200: Thin plate department

201: Rotary table

202: suction cup seat

210: Rough grinding section

211: Rotary grindstone

220: Finishing grinding section

230: Damaged layer removal part

300: DAF attachment part

310: DAF Coating Department

400: DAF division processing department

420: DAF Machining Department

510: Adhesive tape attachment part

520: Support substrate peeling part

530: Enlargement Ministry

535: Adhesive Tape Extensions

536: Adhesive tape peripheral holding part

537: Adhesive tape pusher

538: Adhesive tape pushes the drive part

540: Installation Department

547: Frame Holder

548: Bonding Department

549: Flat Holder

600: Cleaning Department

C: box

S101: Move-in step

S102: Supporting Substrate Subsequent Step

S103: Cutting step

S104: Thinning step

S105: DAF attachment step

S106: DAF segmentation processing steps

S107: Tape Attachment Step

S108: Support substrate peeling step

S109: Enlarging step

S110: Installation steps

S111: Tape cutting step

S112: cleaning step

S113: Moving out step

1 is a plan view showing a substrate processing system according to an embodiment.

FIG. 2 is a perspective view showing a substrate processed by the substrate processing system 1 .

[ Fig. 3] Fig. 3 is a view showing a state in which the support substrate is mounted on the substrate in the support substrate bonding portion.

[ Fig. 4 ] is a diagram showing a cut portion.

[ Fig. 5] Fig. 5 is a view showing a rough polishing portion of a thinned portion.

[ Fig. 6 ] A diagram showing a DAF attachment portion.

[ Fig. 7 ] is a diagram showing a DAF division processing part.

[ Fig. 8] Fig. 8 is a view showing the state of the substrate and the support substrate in the adhesive tape attachment portion.

[ Fig. 9] Fig. 9 is a view showing the state of the substrate and the supporting substrate in the peeling portion of the supporting substrate.

[ Fig. 10 ] is a diagram showing an enlarged portion.

[ Fig. 11 ] is a diagram showing a mounting portion.

[ Fig. 12 ] A diagram showing the state of the substrate in the cleaning section.

13 is a flowchart of the substrate processing method of the embodiment.

[ Fig. 14] Fig. 14 is a diagram showing a laminate structure of a substrate in a modification of the embodiment.

Hereinafter, embodiments will be described with reference to the accompanying drawings. For easy understanding of the description, the same reference numerals are given to the same constituent elements as much as possible in each drawing, and repeated descriptions are omitted.

[embodiment]

An embodiment will be described with reference to FIGS. 1 to 13 . In addition, in the following description, the X direction, the Y direction, and the Z direction are mutually perpendicular directions, the X direction and the Y direction are the horizontal directions, and the Z direction is the vertical direction. The rotation direction centered on the vertical axis is also referred to as the θ direction.

<Substrate processing system>

FIG. 1 is a plan view showing a substrate processing system 1 according to the embodiment. The substrate processing system 1 performs dicing of the substrate 10 , thinning of the substrate 10 , attachment of the DAF to the substrate 10 , expansion of the wafer interval, mounting of the substrate 10 , and the like. The substrate processing system 1 includes a carry-in/out station 20 , a processing station 30 , and a control device 90 .

The cassette C is carried in and out of the carry-in station 20 from the outside. The cassette C accommodates a plurality of substrates 10 at intervals in the Z direction. The carry-in/out station 20 has a mounting table 21 and a transfer area 25 .

The mounting table 21 has a plurality of mounting plates 22 . The plurality of placement plates 22 are arranged in a row along the Y direction. The cassette C is placed on each placement plate 22 . The cassette C on one placement plate 22 accommodates the substrates 10 before processing, and the cassette C on the other placement plate 22 accommodates the substrates 10 after processing.

The transfer area 25 is arranged so as to be adjacent to the mounting table 21 in the X direction. A conveyance path 26 extending in the Y direction and a conveyance device 27 movable along the conveyance path 26 are provided in the conveyance area 25 . The conveying device 27 can be moved not only in the Y direction, but also in the X direction, the Z direction, and the θ direction. The transfer device 27 transfers the substrate 10 between the cassette C placed on the placement plate 22 and the transition portion 35 of the processing station 30 .

The processing station 30 includes a transfer area 31, a transition section 35, and various processing sections to be described later. In addition, the arrangement and the number of the processing units are not limited to those shown in FIG. 1 , and can be arbitrarily selected. In addition, a large number of processing units may be distributed or centrally arranged in arbitrary units.

The conveyance area 31 is provided on the opposite side in the X direction of the conveyance area 25 with reference to the transition portion 35 . The transition part 35 , various processing parts, and the like are provided separately from the conveyance area 31 and are installed so as to surround the conveyance area 31 .

A conveyance path 32 extending in the X direction and a conveyance device 33 movable along the conveyance path 32 are provided in the conveyance area 31 . The conveying device 33 can be moved not only in the X direction, but also in the Y direction, the Z direction, and the θ direction. The transfer device 33 transfers the substrate 10 between the processing units adjacent to the transfer area 31 .

The control device 90 is constituted by, for example, a computer, and includes a CPU (Central Processing Unit) 91 , a recording medium 92 such as a memory, an input interface 93 and an output interface 94 as shown in FIG. 1 . The control device 90 performs various controls by causing the CPU 91 to execute a program stored in the recording medium 92 . In addition, the control device 90 receives signals from the outside through the input interface 93 and sends signals to the outside through the output interface 94 .

The program of the control device 90 is stored in the information recording medium and installed by the information recording medium. Examples of information recording media include hard disk (HD), floppy disk (FD), compact disk (CD), optical disk (MO), memory card, and the like. In addition, programs can be downloaded and installed via Internet routing servers.

<Substrate processed by the substrate processing system>

FIG. 2 is a perspective view showing the substrate 10 after being processed by the substrate processing system 1 . The substrate 10 is mounted on the frame 59 through the adhesive tape 51 after performing processes such as dicing, thinning, attaching the DAF 15, and increasing the interval between the wafers 13.

The adhesive tape 51 is composed of a sheet-like base material and an adhesive coated on the surface of the sheet-like base material. The adhesive tape 51 is attached to the frame 59 so as to cover the opening of the annular frame 59 and is bonded to the substrate 10 in the opening of the frame 59 . Thereby, since the frame 59 can be held and the substrate 10 can be conveyed, the handleability of the substrate 10 can be improved.

A DAF (Die Attach Film) 15 may be provided between the adhesive tape 51 and the substrate 10 as shown in FIG. 2 . DAF 15 series die bonding wafer. DAF 15 is used for bonding of laminated wafers, bonding between wafers and substrates, etc. DAF 15 may be conductive or insulating.

The DAF 15 is formed smaller than the opening of the frame 59 and is provided inside the frame 59 . The DAF covers the entire second main surface 12 of the substrate 10 . In addition, when the lamination of the wafer 13 is not performed, the DAF 15 is not required, so the substrate 10 can be mounted on the frame 59 only through the adhesive tape 51 .

Hereinafter, the support substrate bonding portion 40 , the cutting portion 100 , the thinning portion 200 , the DAF attachment portion 300 , the DAF division processing portion 400 , the adhesive tape attachment portion 510 , and the support substrate peeling portion 520 , which are arranged in the processing station 30 , will be described in order. , the expansion part 530 , the installation part 540 and the cleaning part 600 .

<Support board bonding part>

FIG. 3 is a diagram showing a state in which the support substrate 41 is mounted on the substrate 10 in the support substrate bonding portion 40 . The support substrate bonding unit 40 bonds the support substrate 41 to the substrate 10 before being processed by the substrate processing system 1 . The substrate 10 is a semiconductor substrate such as a silicon wafer and a compound semiconductor wafer, a sapphire substrate, or the like. The first main surface 11 of the substrate 10 before processing is partitioned by forming a plurality of scribe lines in a lattice shape, and device layers 14 including components, circuits, terminals, etc. are formed in the partitioned regions.

The support substrate 41 protects the first main surface 11 of the substrate 10 during processing such as dicing and thinning, and protects the device layer 14 preformed on the first main surface 11 . The supporting substrate 41 is a flat plate-shaped substrate having a diameter approximately the same as that of the substrate 10 and supports the substrate 10 . The support substrate 41 is a transmissive glass substrate in this embodiment. In addition, the support substrate 41 only needs to be a substrate with relatively high rigidity compared to a conventional protective tape, and semiconductor substrates such as silicon wafers and compound semiconductor wafers, and sapphire-based substrates can also be used. Substrates other than glass substrates such as plates. In addition, the support substrate 41 has a function of supporting the substrate 10 and a function as a carrier for transferring the substrate 10 between the various parts of the substrate processing system 1 .

The support substrate bonding portion 40 forms an adhesive layer 42 by applying an adhesive on the first main surface 11 on the device layer 14 side of the substrate 10 , and the substrate 10 is bonded to the support substrate 41 through the adhesive layer 42 . In the present embodiment, the support substrate bonding portion 40 irradiates ultraviolet rays on the bonding layer 42 through the transparent support substrate 41, thereby curing the bonding layer 42 to improve the adhesive force of the bonding layer 42, and bonding the support substrate 41 on the substrate 10 . In addition, in addition to ultraviolet irradiation, a method using heat or a laser can also be used as a method for curing the adhesive layer 42 . In addition, instead of applying the adhesive to the first main surface 11 , the adhesive may be applied on the support substrate 41 side for bonding.

The material of the next layer 42 can be hardened by irradiation or heating of ultraviolet rays, lasers, etc. to improve the adhesive force, and can also be further hardened, softened and modified by irradiation or heating of ultraviolet rays, lasers, etc. in the hardened state. A material that can be easily peeled off due to weak adhesion. As such a material, an ultraviolet curable resin, a thermosetting resin, a thermoplastic resin, etc. are mentioned, for example. Then layer 42 may be composed of a plurality of layers. In this case, only a part of the layer can be degraded and peeled off easily.

<cutting part>

FIG. 4 is a diagram showing the cutting portion 100 . The cutting part 100 performs cutting of the substrate 10 . Here, the dicing of the substrate 10 means a process for dividing the substrate 10 into a plurality of wafers 13 , and in this embodiment, as shown in FIG. 4 , a laser beam is used to form a modified layer inside the substrate 10 as a starting point for fracture. Stealth cleavage (SD) of 16. The cutting unit 100 includes, for example, a substrate holding unit 110 , a substrate processing unit 120 , and a moving mechanism unit 130 .

The substrate holding portion 110 holds the substrate 10 through the support substrate 41 . The substrate 10 is preferably kept horizontal. For example, the first main surface 11 protected by the support substrate 41 of the substrate 10 is the lower surface, and the second main surface 12 of the substrate 10 is the upper surface. The substrate holding portion 110 is, for example, a vacuum chuck.

The substrate processing unit 120 performs, for example, dicing of the substrate 10 held by the substrate holding unit 110 . The substrate processing unit 120 has, for example, a laser oscillator 121 and an optical system 122 for irradiating the substrate 10 with laser light from the laser oscillator 121 . The optical system 122 is composed of a condensing lens or the like for condensing the laser light from the laser oscillator 121 on the substrate 10 .

The moving mechanism unit 130 relatively moves the substrate holding unit 110 and the substrate processing unit 120 . The moving mechanism unit 130 is constituted by, for example, an XYZθ stage or the like that moves the substrate holding unit 110 in the X direction, the Y direction, the Z direction, and the θ direction.

The control device 90 controls the substrate processing unit 120 and the moving mechanism unit 130 , and then performs dicing of the substrate 10 along the dividing lanes dividing the substrate 10 into a plurality of wafers 13 . In the present embodiment, laser light having transmittance to the substrate 10 is used.

In addition, although the supporting substrate bonding portion 40 and the dicing portion 100 are arranged in the processing station 30 of the substrate processing system 1 in the present embodiment, they may be arranged outside the substrate processing system 1 . At this time, after the substrate 10 is diced, it is carried in and out of the carrying-in station 20 from the outside.

<Thin Plated Section>

The thinning section 200 (refer to FIG. 1 ) processes the second main surface 12 on the opposite side of the first main surface 11 protected by the support substrate 41 of the substrate 10 after dicing, thereby thinning the substrate 10 . Formation of components by cutting part 100 At the starting point of slicing (modified layer 16 ), processing stress acts on the substrate 10 during thinning, whereby cracks extend from the starting point of slicing in the thickness direction, and the substrate 10 is divided into a plurality of wafers 13 . For example, as shown in FIG. 1 , the thinning portion 200 includes a turntable 201 , a chuck holder 202 serving as a substrate suction portion, a rough polishing portion 210 , a finishing polishing portion 220 , and a damaged layer removing portion 230 .

The turntable 201 rotates around the center line of the turntable 201 . A large number of (for example, four in FIG. 1 ) suction cup holders 202 are arranged at equal intervals around the rotation center line of the turntable 201 .

Most of the suction cup holders 202 rotate around the center line of the turntable 201 together with the turntable 201 . The center line of the rotary table 201 is vertical. When the turntable 201 is rotated, the suction cup holder 202 facing the rough grinding part 210 , the finishing grinding part 220 and the damaged layer removing part 230 is changed.

The chuck holder 202 sucks the substrate 10 through the support substrate 41 . The suction cup holder 202 is, for example, a vacuum suction cup. The substrate 10 is preferably kept horizontal. For example, the first main surface 11 protected by the support substrate 41 of the substrate 10 is the lower surface, and the second main surface 12 of the substrate 10 is the upper surface.

FIG. 5 is a view showing the rough grinding part 210 of the thinning part 200 . The rough grinding unit 210 performs rough grinding of the substrate 10 . The rough grinding unit 210 has a rotating grindstone 211 as shown in, for example, FIG. 5 . The rotary grindstone 211 rotates and descends with its center line as the center, and then processes the upper surface (ie, the second main surface 12 ) of the substrate 10 held by the suction cup holder 202 . A polishing liquid is supplied on the upper surface of the substrate 10 .

The finishing grinding part 220 performs finishing grinding of the substrate 10 . The structure of the finishing grinding part 220 is substantially the same as that of the rough grinding part 210 . However, the average particle diameter of the abrasive grains of the rotating grindstone of the finishing grinding part 220 is smaller than the average particle diameter of the abrasive grains of the rotating grindstone of the rough grinding part 210 .

The damaged layer removing portion 230 removes the damaged layer formed on the second main surface 12 of the substrate 10 by grinding such as rough grinding and finishing grinding. For example, the damaged layer removing unit 230 supplies a processing liquid to the substrate 10 to perform wet etching treatment, and removes the damaged layer. In addition, the removal method of the damaged layer is not particularly limited.

In addition, the thinned portion 200 may have a polishing portion for polishing the substrate 10 . The structure of the grinding part is substantially the same as that of the rough grinding part 210 . The polishing of the substrate 10 may be exemplified by CMP (Chemical Mechanical Polishing). In addition, the thinned portion 200 may have a gettering portion that forms a gettering portion (for example, a crystal defect or a skew) that traps impurities. Although the number of the suction cup holders 202 is four in FIG. 1 , it can be appropriately changed according to the type of processing. In addition, one of the processing parts (eg, the damaged layer removing part 230 ) can also perform various types of processing (eg, removing the damaged layer and forming a suction part).

<DAF attachment part>

FIG. 6 is a diagram showing the DAF attachment portion 300 . The DAF attachment portion 300 attaches the DAF 15 to the second main surface 12 of the thinned substrate 10 . For example, the DAF attachment portion 300 includes a DAF coating portion 310 that coats the DAF coating liquid containing the DAF 15 material on the second main surface 12 of the thinned substrate 10 . The DAF coating unit 310 is constituted by, for example, a nozzle for discharging the coating liquid for DAF, or the like.

In addition to the DAF coating portion 310 , the DAF attachment portion 300 also has a substrate holding portion 311 that holds the substrate 10 through the support substrate 41 . The substrate 10 is preferably kept horizontal. For example, the first main surface 11 protected by the support substrate 41 of the substrate 10 is the lower surface, and the second main surface 12 of the substrate 10 is the upper surface. The substrate holding portion 311 is, for example, a vacuum chuck.

The DAF application part 310 moves relatively with respect to the substrate holding part 311 , and applies the coating liquid for DAF on the second main surface 12 of the substrate 10 held by the substrate holding part 311 . The coating method is not particularly limited, and examples thereof include a spin coating method, an ink jet method, a screen printing method, and the like.

The coating liquid for DAF contains resin such as acrylic and epoxy, and a solvent for melting the resin, and is contained in a bottle. A flow control valve, a flow meter, etc. are provided in the middle of the piping connecting the bottle and the DAF coating unit 310 .

The coating liquid for DAF is coated on the second main surface 12 of the substrate 10 to form a liquid film. By drying the liquid film, DAF 15 is formed. When the coating liquid for DAF is used, the film thickness of DAF 15 can be changed by changing the film thickness of the liquid film. In addition, the material of DAF 15 can be easily changed by exchanging the bottle of the coating liquid for DAF.

In addition, the DAF attachment portion 300 may be configured such that the DAF 15 is attached to the second main surface 12 of the thinned substrate 10 by a method other than the method shown in FIG. attached to the substrate 10 .

<DAF division processing part 400>

FIG. 7 is a diagram showing the DAF division processing unit 400 . The DAF division processing unit 400 performs division processing of the DAF 15 along the boundary line of the wafer 13 . Here, the division process of the DAF 15 means the process for dividing the DAF 15 , and includes dividing the DAF 15 and forming the starting point of division in the DAF 15 . The DAF division processing unit 400 includes, for example, a substrate holding unit 410 , a DAF processing unit 420 , and a moving mechanism unit 430 .

The substrate holding portion 410 holds the substrate 10 through the support substrate 41 . The substrate 10 is preferably kept horizontal. For example, the first major surface 11 protected by the support substrate 41 of the substrate 10 is the lower surface, and the second major surface 12 of the substrate 10 to which the DAF 15 is attached is the upper surface. The substrate holding portion 410 is, for example, a vacuum chuck.

The DAF processing section 420 performs, for example, a division processing of the DAF 15 attached to the substrate 10 held by the substrate holding section 410 . The DAF processing unit 420 has, for example, a laser oscillator 421 and an optical system 422 that irradiates the DAF 15 with laser light from the laser oscillator 421 . The optical system 422 is composed of a condensing lens or the like for condensing the laser light from the laser oscillator 421 on the DAF 15 .

The moving mechanism unit 430 relatively moves the substrate holding unit 410 and the DAF processing unit 420 . The moving mechanism unit 430 is constituted by, for example, an XYZθ stage or the like that moves the substrate holding unit 410 in the X direction, the Y direction, the Z direction, and the θ direction.

The control device 90 controls the DAF processing unit 420 and the moving mechanism unit 430 to perform the division processing of the DAF 15 along the boundary line of the plurality of wafers 13 . A modified layer serving as a fracture origin may be formed inside the DAF 15, and a laser processing groove may be formed on the laser-irradiated surface of the DAF 15 (for example, the upper surface in FIG. 7). The laser machined trenches may or may not penetrate the DAF 15 in the film direction.

When forming the modified layer inside the DAF 15, a laser light having translucency to the DAF 15 is used. On the other hand, when forming a laser processing groove on the laser-irradiated surface of the DAF 15, a laser light having an absorptivity to the DAF 15 is used.

In addition, although the DAF processing part 420 has a laser oscillator for irradiating the DAF 15 with laser light in the present embodiment, it may have a cutter for cutting the DAF 15 or a scribe for forming a scribe groove on the surface of the DAF 15. wire.

<Adhesive tape attachment part>

FIG. 8 is a view showing the state of the substrate 10 and the support substrate 41 in the adhesive tape attaching portion 510 . The adhesive tape attaching portion 510 attaches the adhesive tape 51 to the second main surface 12 of the substrate 10 to which the DAF 15 is attached. The adhesive tape attaching portion 510 is, for example, as shown in FIG. 8, the adhesive tape 51 is placed on a stage or the like with the adhesive surface facing upward, and then the surface of the DAF 15 attached to the second main surface 12 of the substrate 10 is placed on the surface of the adhesive tape 51. The adhesive surfaces are adhered together, whereby the adhesive tape 51 is attached to the side of the second main surface 12 of the substrate 10 . At this time, as shown in FIG. 8 , the first main surface 11 protected by the support substrate 41 of the substrate 10 is the lower surface, and the second main surface 12 of the substrate 10 to which the DAF 15 is attached is the upper surface.

<Support substrate peeling part>

FIG. 9 is a view showing the state of the substrate 10 and the support substrate 41 in the support substrate peeling portion 520 . The support substrate peeling portion 520 peels off the support substrate 41 from the substrate 10 . When the interval between the plurality of wafers 13 constituting the substrate 10 is widened, the support substrate 41 can be prevented from becoming an obstacle.

The support substrate peeling portion 520 , for example, irradiates the adhesive layer 42 with ultraviolet rays through the support substrate 41 to further harden the adhesive layer 42 hardened by the support substrate adhesive portion 40 to reduce the adhesive force. After the adhesion of the subsequent layer 42 is reduced, the support substrate 41 can be easily peeled off from the substrate 10 by a peeling operation. In addition, the adhesive force of the adhesive layer 42 may be reduced by heating or laser irradiation instead of ultraviolet irradiation.

<Extension Department>

FIG. 10 is a diagram showing the enlarged portion 530 . The enlargement part 530 enlarges the space|interval of the many wafers 13 which comprise the board|substrate 10 to which the DAF 15 is attached. By enlarging the interval between the wafers 13, grinding at the time of transfer or pick-up can be suppressed.

The enlarged portion 530 has, for example, an adhesive tape extension 535 that expands the spacing between the wafers 13 by radially extending the adhesive tape 51 attached to the substrate 10 through the DAF 15 . The adhesive tape extending portion 535 has, for example, an adhesive tape outer periphery holding portion 536 , an adhesive tape pressing portion 537 , and an adhesive tape pressing driving portion 538 .

The adhesive tape outer peripheral holding portion 536 holds the outer peripheral portion of the adhesive tape 51 . The adhesive tape outer peripheral holding portion 536 is formed, for example, in a ring shape. An annular gap is formed between the outer peripheral holding portion 536 of the adhesive tape and the substrate 10 disposed inside the outer peripheral holding portion 536 of the adhesive tape.

The adhesive tape pressing portion 537 presses the adhesive tape 51 between the inner periphery of the adhesive tape outer periphery holding portion 536 and the outer periphery of the substrate 10 attached to the adhesive tape 51 held by the adhesive tape outer periphery holding portion 536 . The adhesive tape pressing portion 537 is formed, for example, in a cylindrical shape.

The adhesive tape pressing driving unit 538 relatively moves the adhesive tape outer periphery holding unit 536 and the adhesive tape pressing unit 537 . The moving direction is perpendicular to the main surface (eg, the first main surface 11 ) of the substrate 10 , and is, for example, a vertical direction. The adhesive tape pressing driving unit 538 is constituted by a pneumatic cylinder or the like.

The control device 90 controls the adhesive tape pressing driving unit 538, and then presses the adhesive tape 51 so that the adhesive tape 51 radially extends. Thereby, the interval between the wafers 13 can be enlarged, so that a gap can be formed between the wafers 13 .

<Installation Department>

FIG. 11 is a diagram showing the mounting portion 540 . The mounting portion 540 mounts the substrate 10 with the space between the wafers 13 widened on the frame 59 through the DAF 15 and the adhesive tape 51 .

For example, the mounting portion 540 includes a frame holding portion 547 that holds the frame 59 , and an adhesive portion 548 that mounts the substrate 10 to the frame 59 held by the frame holding portion 547 through the adhesive tape 51 and the DAF 15 . The adhesive portion 548 has, for example, a flat holding portion 549 that keeps the mounting portion 52 of the adhesive tape 51 mounted on the frame 59 flat, and a moving mechanism portion 550 that relatively moves the flat holding portion 549 and the frame holding portion 547 .

The mounting portion 52 of the adhesive tape 51 mounted on the frame 59 is kept flat by the flat holding portion 549 , and one side is kept parallel to the frame 59 and is relatively close to the frame 59 , and then adhered to the frame 59 . On the other hand, the remaining portion 53 of the adhesive tape 51 that is not mounted on the frame 59 can be cut out by a cutter or the like. Since the mounting portion 52 of the adhesive tape 51 mounted on the frame 59 is not loose, the space between the chips 13 can be maintained.

<Cleaning Department>

FIG. 12 is a diagram showing the state of the substrate 10 in the cleaning unit 600 . The cleaning unit 600 cleans the first main surface 11 of the substrate 10 from which the support substrate 41 is peeled off. Thereby, the adhesive layer 42 remaining on the first main surface 11 is removed.

<Substrate processing method>

Next, a substrate processing method using the substrate processing system 1 having the above-described configuration will be described. FIG. 13 is a flowchart showing the substrate processing method of the embodiment.

As shown in FIG. 13 , the substrate processing method includes: a loading step S101, a supporting substrate attaching step S102, a cutting step S103, a thinning step S104, a DAF attaching step S105, a DAF dividing process step S106, a tape attaching step S107, and a supporting substrate peeling off Step S108, expansion step S109, installation step S110, a tape cutting step S111, a cleaning step S112, and a carrying-out step S113. These steps are carried out under the control of the control device 90 . In addition, the order of these steps is not limited to the order shown in FIG. 13 .

In the transfer step S101 , the transfer device 27 transfers the substrate 10 from the cassette C on the stage 21 to the transition portion 35 of the processing station 30 , and then the transfer device 33 transfers the substrate 10 from the transition portion 35 to the support substrate attachment portion 40 .

In the support substrate bonding step S102 , as shown in FIG. 3 , the support substrate bonding portion 40 coats the bonding agent on the first main surface 11 on the device layer 14 side of the formation substrate 10 to form the bonding layer 42 , and then the bonding layer 42 is formed by bonding Layer 42 will support substrate 41 on substrate 10 . The support substrate bonding portion 40 , for example, irradiates the bonding layer 42 with ultraviolet rays through the support substrate 41 , thereby curing the bonding layer 42 and bonding the support substrate 41 to the substrate 10 . In addition, instead of applying the adhesive to the first main surface 11 , the adhesive may be applied to the support substrate 41 side for bonding.

In the dicing step S103 , as shown in FIG. 4 , the dicing part 100 performs dicing of the substrate 10 along the dividing lanes dividing the substrate 10 into a plurality of wafers 13 .

In the thinning step S104 , as shown in FIG. 5 , the thinning section 200 thins the substrate 10 by processing the second main surface 12 on the opposite side of the first main surface 11 protected by the support substrate 41 of the substrate 10 . . At this time, the first main surface 11 side of the substrate 10 is held by the support substrate 41 .

In the DAF attaching step S105 , as shown in FIG. 6 , the DAF attaching part 300 attaches the DAF 15 to the second main surface 12 of the thinned substrate 10 . For example, in the DAF attachment step S105 , a coating liquid for DAF containing a material of the DAF 15 is applied on the second main surface 12 of the thinned substrate 10 .

The coating liquid for DAF is coated on the second main surface 12 of the substrate 10 to form a liquid film. By drying the liquid film, DAF 15 is formed. When the coating liquid for DAF is used, the film thickness of DAF 15 can be changed by changing the film thickness of the liquid film. In addition, the material of DAF 15 can be easily changed by exchanging the bottle of the coating liquid for DAF.

In addition, in the DAF attaching step S105 , the DAF attaching part 300 may also attach the DAF 15 pre-formed in a film shape to the second main surface 12 of the thinned substrate 10 . Since the DAF 15 is preformed in a film shape, the DAF 15 can be prevented from scattering around the substrate 10 .

In the DAF dividing processing step S106 , as shown in FIG. 7 , the DAF dividing processing unit 400 divides and processes the DAF 15 along the boundary line of the wafer 13 .

In addition, the enlargement step S109 may be performed without performing the DAF division processing step S106. The DAF 15 can be torn along the boundary line of the wafers 13 by expanding the interval between the wafers 13 in the expanding step S109 .

In the present embodiment, the DAF dividing step S106 is performed after the DAF attaching step S105 and before the expanding step S109. Therefore, DAF 15 with low tear properties can be used, so there are many types of DAF 15 to choose from.

In the tape attaching step S107 , as shown in FIG. 8 , the adhesive tape attaching portion 510 attaches the adhesive tape 51 to the second main surface 12 of the substrate 10 to which the DAF 15 is attached.

In the support substrate peeling step S108 , as shown in FIG. 9 , the support substrate peeling portion 520 peels off the support substrate 41 from the substrate 10 . The support substrate peeling portion 520 irradiates, for example, ultraviolet rays through the support substrate 41 to the adhesive layer 42, thereby further curing the adhesive layer 42 hardened by the support substrate followed by step S102 to reduce the adhesive force. After the adhesion of the subsequent layer 42 is reduced, the support substrate 41 can be easily peeled off from the substrate 10 by a peeling operation. In addition, the adhesive force of the adhesive layer 42 may be reduced by heating or laser irradiation instead of ultraviolet irradiation.

In the enlarging step S109 , as shown in FIG. 10 , the enlarging portion 530 enlarges the interval of the majority of the wafers 13 constituting the substrate 10 to which the DAF 15 is attached. By enlarging the interval between the wafers 13, grinding at the time of transfer or pick-up can be suppressed.

For example, in the enlarging step S109 , the adhesive tape 51 attached to the substrate 10 through the DAF 15 is radially extended, thereby enlarging the interval between the wafers 13 . The space between the enlarged chips 13 can be maintained by the extended adhesive tape 51 .

In the mounting step S110 , as shown in FIG. 11 , the mounting portion 540 mounts the substrate 10 with the space between the wafers 13 widened on the frame 59 through the DAF 15 and the adhesive tape 51 . For example, in the mounting step S110 , the mounting portion 52 of the adhesive tape 51 mounted on the frame 59 is kept flat, and the adhesive tape 51 is adhered to the frame 59 at the same time. Since the mounting portion 52 of the adhesive tape 51 mounted on the frame 59 is not loose, the space between the chips 13 can be maintained. Thereby, as shown in FIG. 11 , the substrate 10 is held on the frame 59 through the DAF 15 and the adhesive tape 51 in a state where the interval between the wafers 13 is widened.

In the cleaning step S111 , after attaching the frame 59 to the adhesive tape 51 , the attachment portion 540 cuts off the remaining portion 53 of the adhesive tape 51 that is not attached to the frame 59 with a cutter or the like.

In the cleaning step S112 , as shown in FIG. 12 , the cleaning unit 600 cleans the first main surface 11 of the substrate 10 from which the support substrate 41 is peeled off. Thereby, the adhesive layer 42 remaining on the first main surface 11 is removed.

In the unloading step S113 , the transport device 33 transports the substrate 10 from the cleaning unit 600 to the transition section 35 , and then the transport device 27 transports the substrate 10 from the transition section 35 to the cassette C on the mounting table 21 . The transfer device 33 or the transfer device 27 holds the frame 59 and transfers the substrate 10 . The cassette C is carried out from the mounting table 21 to the outside. Each wafer 13 of the substrate 10 carried out to the outside is picked up. In this way, a semiconductor device including the wafer 13 and the DAF 15 is produced.

In addition, in the above-mentioned substrate processing method, for example, when the lamination of the wafer 13 is not performed, the DAF 15 is not required, so the DAF attachment step S105 and the DAF division processing step S106 may not be performed. At this time, the DAF 15 is not disposed between the adhesive tape 51 and the substrate 10 (wafer 13 ) after the substrate 10 (refer to FIG. 2 ) processed by the substrate processing system 1 , and the substrate 10 is only mounted on the frame 59 through the adhesive tape 51 .

Next, the effects of the substrate processing method of the present embodiment will be described. The substrate processing method includes: a supporting substrate followed by step S102, in which the supporting substrate 41 is adhered to the first main surface 11 on the side of the device layer 14 forming the substrate 10; a cutting step S103, which is supported by the supporting substrate followed by the step S102. The second main surface 12 on the opposite side of the first main surface 11 of the substrate 41 is subjected to stealth dicing of the substrate 10; and the thinning step S104 is to grind the second main surface 12 of the substrate 10 after the stealth dicing by the dicing step S103 to The substrate 10 is thinned.

Here, for example, a conventional substrate processing method as described in Patent Document 1 is considered as a comparative example. In the conventional substrate processing method, when the substrate 10 is thinned, the first main surface 11 of the substrate is protected by a protective tape. Regarding the thinning step S104 of the present embodiment shown in FIG. 5 , the second main surface 12 is polished by placing the substrate 10 on the suction cup holder 202 through a protective tape.

In such a structure in which the device layer 14 of the first main surface 11 of the substrate 10 is protected by the protective tape, as in the present embodiment, stealth dicing of the substrate 10 is performed first by the dicing step S103 , and then the substrate is performed by the thinning step S104 When the thickness of 10 is reduced, since the rigidity of the protective tape for protecting each wafer 13 is low, there is a possibility that the relative position of each wafer 13 may fluctuate and processing stability may be insufficient. For example, in the thinning step S104, processing stress acts on the substrate 10 during the thinning process, whereby cracks are formed by the modified layer 16 inside the substrate 10 by stealth dicing in the cutting step S103 (please refer to FIG. 4) The substrate 10 is stretched in the thickness direction, and the substrate 10 is divided into a plurality of wafers 13 . At this time, since the protective tape holding the wafers 13 from below is soft, the bases of the wafers 13 are unstable, and therefore, corner cracks are likely to occur in the wafers 13 . In addition, in order to miniaturize the size of the wafer 13, the number of the modified layers 16 produced by stealth dicing must be increased in the dicing step S103, but since each modified layer 16 expands inside the substrate 10, the number is increased too much. The substrate 10 is warped due to the influence of the expansion of the modified layer 16, and there is a possibility that the warpage cannot be suppressed by the protective tape with low rigidity.

For such a problem, in the present embodiment, a support substrate 41 is used to protect the first main surface 11 of the substrate 10 in place of the conventional protective tape. Since the support substrate 41 is mounted on the substrate 10 by an adhesive, a substrate formed of a material having higher rigidity than a conventional protective tape can be used as the support substrate 41 . Therefore, in the thinning step S104 , as shown in FIG. 5 , the second main surface 12 is polished in a state where the substrate 10 is placed on the support substrate 41 having higher rigidity than the conventional protective tape. Thereby, even if the substrate 10 is divided into a plurality of wafers 13 during the thinning process, each wafer 13 is positioned on the hard support substrate 41 and the base of each wafer 13 is stable, so that the occurrence of corner cracking in the wafer 13 can be suppressed. In addition, even if the substrate 10 is warped due to the expansion of the modified layer 16 generated by the stealth dicing in the dicing step S103 inside the substrate 10, because the substrate 10 is placed on the support substrate 41 with higher rigidity than the conventional protective tape Since the dicing is performed, the occurrence of warpage of the substrate 10 can be suppressed favorably. From the above, it can be seen that the substrate processing method of the present embodiment can improve the processing stability of the semiconductor device.

In addition, in the substrate processing method of the present embodiment, after the support substrate 41 is peeled off from the substrate 10 in the support substrate peeling step S108, the expansion step S109 or the mounting step S110 are performed, so that the first step of protecting the substrate 10 is to use the support substrate 41 with high rigidity. The cutting step S103 or the thinning step S104 is performed on the main surface 11 , and the enlarging step S109 or the mounting step S110 can also be performed well without being affected by the rigidity of the support substrate 41 .

In addition, in the substrate processing method of the present embodiment, after the DAF attaching step S105 and before the tape attaching step S107, the DAF dividing processing step S106 of dividing and processing the DAF 15 attached to the substrate 10 along the boundary of the wafer 13 is performed. By dividing the DAF 15 in advance, the interval between most of the wafers 13 can be easily enlarged in the enlargement step S109.

In addition, in the substrate processing method of the present embodiment, a glass substrate formed of glass is used as the support substrate 41 . Since the glass substrate transmits ultraviolet rays, the adhesive can be cured by ultraviolet rays without heating. Therefore, the formation of the adhesive layer 42 and the increase or decrease of the adhesive force after the formation of the adhesive layer, etc., can be performed at room temperature. Additionally, the adhesive layer can be heated to promote hardening of the adhesive.

[Variation]

A modification of the above-described embodiment will be described with reference to FIG. 14 . As shown in FIG. 14 , bumps 14 a are sometimes provided on the device layer 14 formed on the first main surface 11 of the substrate 10 .

In the conventional method described in Patent Document 1, a protective tape is pasted over the bumps 14a. At this time, the first main surface 11 of the substrate 10 can be uneven by whether there are bumps 14a on the surface of the protective tape. Therefore, the TTV (total thickness variation (total thickness variation) of the second main surface 12 of the substrate 10 that has been thinned in the thinning step S104 thickness variation)) worsens. For example, the portion of the substrate 10 with the bumps 14a is more likely to be ground than the portion without the bumps 14a, so that the unevenness after grinding becomes larger. In addition, since gaps are formed between the bumps 14a, the polishing liquid penetrates between the bumps 14a during polishing, thereby contaminating the substrate 10 after polishing. In addition, since the flatness of the surface of the protective tape is poor, there is a possibility that the substrate 10 has poor suction in the thinning step S104 and the cutting step S103 and the like.

For such a problem, in the modification of the present embodiment, in step S102 of attaching the support substrate shown in the flowchart of FIG. On the first main surface 11, the gaps of the bumps 14a are filled with an adhesive. Next, an adhesive layer 42 larger than the height of the bumps 14a is formed, thereby filling the unevenness of the device layer 14 and flattening the surface. The support substrate 41 is bonded to the substrate 10 by the bonding layer 42 .

With this structure, the adhesive can be used to fill the spaces between the bumps 14 a to planarize the surface of the device layer 14 , so that the support substrate 41 can be adhered to the first main surface 11 of the substrate 10 well and without gaps. Thereby, in the thinning step S104, the TTV of the second main surface 12 of the thinned substrate 10 can be improved. In addition, in the thinning step S104 , the polishing liquid can be prevented from infiltrating between the bumps 14 a during the polishing of the substrate 10 , so that the substrate 10 after polishing can be prevented from being contaminated. In addition, since the support substrate 41 of the glass substrate abuts against the suction cup holder 202 instead of the conventional protective tape, poor suction of the substrate 10 can be prevented in the thinning step S104 and the cutting step S103 and the like. Therefore, the adhesive layer 42 can be formed flat regardless of the element shape or size of the device layer 14 , so that the support substrate 41 can be reliably bonded to the substrate 10 .

The present embodiment has been described above with reference to specific examples. However, the present disclosure is not limited to these specific examples. As long as the features of the present disclosure are present, those with ordinary knowledge in the technical field to which the present disclosure pertains to add appropriate design changes to these specific examples are also included in the scope of the present disclosure. Elements of each of the foregoing specific examples The arrangement, conditions, shapes and the like thereof are not particularly limited to those illustrated, and can be appropriately changed. For example, the supporting substrate bonding portion 40 , the cutting portion 100 , and the thinning portion 200 are not specific examples described in the aforementioned embodiments of the present invention with reference to the accompanying drawings, and the elements included in each of the foregoing specific examples can be used as long as there is no technical conflict. Change the appropriate combination.

S101: Move-in step

S102: Supporting Substrate Subsequent Step

S103: Cutting step

S104: Thinning step

S105: DAF attachment step

S106: DAF segmentation processing steps

S107: Tape Attachment Step

S108: Support substrate peeling step

S109: Enlarging step

S110: Installation steps

S111: Tape cutting step

S112: cleaning step

S113: Moving out step

Claims (10)

A substrate processing method comprising: a step of attaching a support substrate to a first main surface of a device layer side where the substrate is formed; and a step of dicing by connecting the support substrate with the step of attaching the support substrate On the second main surface opposite to the first main surface, a modified layer serving as a fracture origin is formed inside the substrate; in the thinning step, the second main surface of the substrate on which the cutting step has been performed is ground, so that the The substrate is thinned; the DAF attaching step is to attach DAF (Die Attach Film) on the second main surface of the substrate, and the substrate is thinned by the thinning step and then On the supporting substrate; a DAF dividing process step, which is followed by the DAF attaching step, along the boundary of the majority of the wafers constituting the substrate, dividing and processing the DAF attached to the substrate next to the supporting substrate; the tape attaching step, which is attaching an adhesive tape to the DAF on the substrate next to the support substrate; and a support substrate peeling step, which peels off the support substrate from the substrate after the tape attaching step. The substrate processing method of claim 1 of the scope of the application further comprises: an enlarging step, after the supporting substrate peeling step, by extending the adhesive tape to enlarge the interval of most of the chips constituting the substrate divided by the DAF; and a mounting step, the substrate with the space between the chips enlarged by the enlarging step is mounted on the frame through the adhesive tape. For the substrate processing method of claim 1 or 2 of the scope of the application, wherein, In the DAF division processing step, the DAF is irradiated with laser light to divide and process the DAF. The substrate processing method of claim 2 of the claimed scope further comprises: a tape cutting step, after the mounting step, cutting off the remaining part of the adhesive tape not mounted on the frame. The substrate processing method of claim 2 of the claimed scope further comprises: a cleaning step, after the mounting step, cleaning the first main surface of the substrate from which the support substrate is peeled off. The substrate processing method according to any one of claims 1, 2, 4 and 5, wherein bumps are provided on the first main surface of the substrate, and in the step of attaching the support substrate, an adhesive is applied On the first main surface of the substrate, an adhesive layer having a height greater than that of the bump is formed, and the support substrate is attached to the substrate through the adhesive layer. A substrate processing system having: a DAF attachment portion that holds a support substrate attached to a substrate on a first main surface on a side where a device layer is formed and a second main surface on the opposite side from the first main surface The main surface is formed with a modified layer as a starting point of fracture, and then the second main surface is ground and thinned, and the DAF attachment portion attaches DAF (Die Attach Film) to the support substrate. On the second main surface of the substrate; a DAF dicing process part along the boundary of the majority of the wafers, dicing process attached to the DAF on the substrate next to the support substrate, and the wafers constituted by the DAF attached the substrate to which the DAF is partially attached; an adhesive tape attaching part that attaches an adhesive tape to the DAF next to the second main surface of the substrate of the support substrate; and a conveying device that attaches an adhesive tape to the DAF attaching part, the DAF dividing processing part and the adhesive tape Between the attachment portions, the substrate followed by the support substrate is conveyed; and the support substrate peeling portion peels off the support substrate by adhering the substrate with the adhesive tape by the adhesive tape attachment portion. The substrate processing system according to claim 7 of the scope of the application further comprises: an expansion part for expanding the interval between a plurality of chips by extending the adhesive tape, and the chips constitute a part of peeling off the support substrate by the support substrate peeling part the substrate; and a mounting portion, which mounts the substrate with the space between the chips enlarged by the enlarged portion on the frame through the adhesive tape. The substrate processing system according to claim 7 or 8 of the scope of the application further comprises: a supporting substrate bonding part for bonding the supporting substrate to the first main surface of the substrate; a cutting part for attaching the supporting substrate to the first main surface of the substrate; The second main surface of the substrate, which is the support substrate, is connected to a subsequent portion, and a modified layer serving as a fracture origin is formed inside the substrate; and a thinned portion that grinds the substrate on which the modified layer is formed by the cutting portion of the second main surface to thin the substrate. The substrate processing method according to claim 7 or 8, wherein the DAF is divided into a processing part, and the DAF is irradiated with laser light to divide and process the DAF.

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