Protective component forming device

Abstract

A protective component forming device is provided, which can place a sheet on a stage without wrinkling the sheet. The protective component forming device includes: a stage for placing the sheet, which has a chuck table surrounded by a frame; a plurality of air supply ports, which are respectively formed in the frame and connected to an air supply source; a movable holding unit, which faces the stage and holds the wafer; a resin supply unit, which supplies liquid resin onto the sheet; and a pressing pad, which is supported to be movable in the vertical direction at a position facing the sheet. The pressing pad contacts a portion of the sheet placed on the stage in an area inside the plurality of air supply ports to press the sheet.

Description

Technical Field

[0001] The present invention relates to a device for forming a protective component on a first surface of a wafer. Background Art

[0002] When a cylindrical ingot is sliced ​​by a wire saw to form a disc-shaped wafer, warping or undulation occurs on the wafer during slicing. In order to remove the warping or undulation, the following technology is known in the past: a resin is applied to the first surface of the wafer and hardened to form a protective member (for example, see Patent Document 1).

[0003] Patent Document 1: Japanese Patent Application Publication No. 2016-167546

[0004] In this technology, a resin is supplied (dropped) onto a wafer placed on a stage, and the wafer is pressed toward the resin, thereby evenly coating the lower surface (first surface) of the wafer with the resin to form a protective member. However, in the conventional structure, there is a problem that the wafer wrinkles when placed on the stage. Summary of the invention

[0005] Therefore, an object of the present invention is to provide a protective member forming apparatus capable of placing a sheet on a stage without causing the sheet to wrinkle.

[0006] According to the present invention, a protective component forming device is provided, which forms a protective component on the first surface of a chip having a first surface and a second surface on the side opposite to the first surface, wherein the protective component forming device comprises: a carrier, which carries a chip, and has a chuck worktable surrounded by a frame, in which a plurality of air supply ports respectively connected to an air supply source are formed; a movable holding unit, which faces the carrier and holds the chip; a resin supply unit, which supplies resin to the chip; a chip pressing pad, which is supported to be movable in the up and down directions at a position facing the chip; and a control unit, which controls the movement of the holding unit, the resin supply unit and the chip pressing pad, the control unit controlling as follows: air is supplied from the air supply source while the chip pressing pad is in contact with the central portion of the chip placed on the carrier, so that the area of ​​the chip that is not in contact with the chip pressing pad floats from the carrier and slides toward the peripheral direction, thereby stretching the wrinkles of the chip.

[0007] According to this structure, the sheet pressing pad contacts a portion of the sheet placed on the stage and covering the plurality of air supply ports at a region inside the plurality of air supply ports to press the sheet, so that by supplying air from the air supply ports, the region of the sheet not in contact with the sheet pressing pad floats from the stage and slides toward the outer circumference, thereby stretching the wrinkles of the sheet. Therefore, the sheet can be placed on the stage without wrinkling.

[0008] The frame of the stage is preferably coated with fluororesin.

[0009] According to the present invention, the sheet pressing pad contacts a portion of the sheet placed on the stage and covering the plurality of air supply ports at a region on the inner side of the plurality of air supply ports to press the sheet, so that the region of the sheet not in contact with the sheet pressing pad floats from the stage and slides toward the outer circumference by supplying air from the air supply ports, thereby stretching the wrinkles of the sheet. Therefore, the sheet can be placed on the stage without wrinkling. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a schematic diagram of a protective member forming device according to an embodiment of the present invention.

[0011] Figure 2 is a schematic diagram of an ingot and wafers sliced ​​from the ingot.

[0012] Figure 3 It is a top view of the carrier.

[0013] Figure 4 This is a schematic cross-sectional view showing the operation of placing a sheet on the stage.

[0014] Figure 5 2 is a schematic cross-sectional view showing an action of performing wrinkle removal of a sheet.

[0015] Figure 6 1 is a schematic cross-sectional view showing a sheet placed on a stage after wrinkle removal has been performed.

[0016] Figure 7 is a schematic cross-sectional view showing the operation of supplying liquid resin onto a chip.

[0017] Figure 8 It is a schematic cross-sectional view showing the operation of transferring a wafer onto the liquid resin.

[0018] Fig. 9 This is a schematic cross-sectional view showing the operation of hardening the liquid resin to form a wafer protection member.

[0019] Description of symbols

[0020] 1: wafer; 1A: upper surface; 1B: lower surface (first surface); 3: sheet; 3A: inner area; 3B: outer area (area of ​​the sheet not in contact with the sheet pressing pad); 10: carrier; 11: carrier body (frame); 11A: upper surface; 12: glass table (chuck worktable); 13: lamp; 14: air supply port; 16: air supply source; 30: sheet pressing unit; 33: pad frame; 34: pressing pad (sheet pressing pad); 34A: central part; 34B: outer edge; 40: resin supply unit; 41: supply nozzle; 42: liquid resin (resin); 43: protective component; 50: wafer transport unit (holding unit); 52: holding part; 52A: lower surface (holding surface); 60: control unit; 100: protective component forming device. DETAILED DESCRIPTION

[0021] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The present invention is not limited by the contents described in the following embodiments. In addition, the constituent elements described below include contents that can be easily thought of by those skilled in the art, and substantially the same contents. In addition, the structures described below can be appropriately combined. In addition, various omissions, substitutions or changes in the structure can be made within the scope of the gist of the present invention.

[0022] Figure 1 It is a schematic diagram of the protective member forming device of this embodiment. Figure 2 Schematic diagram of a wafer on which a protective member is to be formed using a protective member forming apparatus. Figure 2 As shown, the wafer 1 on which the protective component is to be formed using the protective component forming device of the present embodiment is a wafer before the device pattern is formed, for example, an original sliced ​​wafer obtained by slicing (cutting) a cylindrical ingot 2 of silicon (Si), gallium arsenide (GaAs), silicon carbide (SiC), etc. into a disc shape by a wire saw (not shown). This wafer 1 includes deformation elements such as undulations or warping generated when it is cut by the wire saw on both sides (upper surface 1A and lower surface 1B). In order to remove these undulations or warping, for example, after the lower surface 1B (first surface) of the wafer 1 is coated with resin to form the protective component, both sides of the wafer 1 are ground and flattened in sequence.

[0023] like Figure 1 As shown, the protective member forming device 100 of this embodiment includes a stage 10, a sheet conveying device 20, a sheet pressing unit 30, a resin supply unit 40, a wafer conveying unit (holding unit) 50, and a control unit 60. Figure 1 1 and 2 schematically show the components of the protective member forming device 100, and do not show the arrangement relationship of the components. Next, the components of the protective member forming device 100 will be described.

[0024] Figure 3 The carrier 10 functions as a workbench when forming a protective component on the first surface of the wafer 1. Figure 3 As shown, the stage 10 includes: a stage body (frame) 11 formed in a frame shape; a glass table (chuck table) 12 provided on the upper portion of the stage body 11; and a plurality of UV (ultraviolet) lamps 13 disposed in the stage body 11. Figure 3 As shown in FIG. 1 , the stage body 11 is formed in a rectangular shape when viewed from above, and a circular glass stage 12 is provided in the center. That is, the glass stage 12 is surrounded by the stage body 11 as a frame. The upper surface 12A of the glass stage 12 is formed flat and serves as a placement surface for the sheet 3. In addition, the glass stage 12 does not need to be glass as long as it is a material that transmits the ultraviolet rays irradiated by the lamp 13.

[0025] On the stage body 11, a plurality of air supply ports 14 are provided around the glass stage 12. In this embodiment, Figure 3 As shown in FIG. 1 , a plurality of air supply ports 14 are arranged in an annular shape at intervals around the circular glass stage 12. These air supply ports 14 are connected to an air supply source 16 via a supply path 15, and air is ejected from each of the air supply ports 14. Figure 1 In the embodiment, the air supply port 14 is formed perpendicular to the upper surface 11A of the stage body 11, but it is preferable that the air supply port 14 is formed radially toward the outside of the glass stage 12. In addition, on the stage body 11, a plurality of suction ports (not shown) are arranged in a circular ring outside the air supply port 14. These suction ports are connected to a suction source (not shown) and can suck and hold the sheet 3 on the stage 10 by applying suction to the mounting surface.

[0026] In addition, if Figure 1 As shown in FIG. 1 , a coating process (front surface processing) based on, for example, fluororesin is applied to the upper surface 11A of the stage body 11. Fluororesin has a much lower friction coefficient than metal, so the sheet 3 placed on the stage 10 slides well on the upper surface 11A of the stage body 11. In addition, such coating process is sometimes applied to the entire upper surface 11A of the stage body 11, but it may be applied partially as long as it extends continuously and radially from the glass stage 12.

[0027] like Figure 1 As shown, the sheet conveying device 20 conveys the sheet 3 and places it on the stage 10. The sheet 3 prevents the liquid resin from dripping directly onto the stage 10, thereby protecting the upper surface of the stage 10 from being scratched and preventing the trouble of cleaning. In addition, the sheet 3 makes it easy to handle the wafer 1 coated with the liquid resin. The sheet 3 has a certain degree of softness, such as Figure 3As shown, the sheet 3 is formed to be equal to or slightly smaller than the stage 10. The shape of the sheet 3 is formed into a rectangle (quadrangle) like the stage 10, but it is not limited to this and can also be formed into a circle, etc. In addition, the material of the sheet 3 is polyolefin, PET (polyethyleneterephthalate) or the like.

[0028] The sheet conveying device 20 includes: a conveying arm 21 extending in the horizontal direction; an adsorption pad 22 provided on the lower surface of the conveying arm 21 to adsorb the sheet 3; a lifting unit 23 to lift the conveying arm 21 relative to the stage 10; and a horizontal moving mechanism (not shown) to move the lifting unit 23 in the horizontal direction. The horizontal moving mechanism moves the conveying position of the conveying arm 21 supported by the lifting unit 23 on the stage 10 and away from the stage 10. Figure 1 The suction pad 22 is connected to a suction source (not shown) to suck or release the sheet 3. The lifting unit 23 supports one end of the conveying arm 21 to move the conveying arm 21 in the up-down direction. The sheet 3 is sucked by the suction pad 22 and held by the conveying arm 21, and is conveyed from the withdrawn position to the conveying position above the stage 10.

[0029] The sheet pressing unit 30 presses a portion (central portion) of the sheet 3 placed on the stage 10. The sheet pressing unit 30 includes: a unit body 31 extending in the horizontal direction; an arm 32 extending downward from the lower surface of the unit body 31; a pad frame 33 connected to the arm 32 and supported to be substantially parallel to the unit body 31; a pressing pad (sheet pressing pad) 34 supported by the pad frame 33; a lifting unit 35 that lifts and lowers the unit body 31 (pressing pad 34) relative to the stage 10 (sheet 3); and a horizontal moving mechanism (not shown) that moves the lifting unit 35 in the horizontal direction. The horizontal moving mechanism moves the pressing position of the pressing pad 34 supported by the lifting unit 35 on the stage 10 to a position away from the stage 10. Figure 1 Move between the indicated retracted positions.

[0030] The pad frame 33 is formed into a frame body, for example, in a circular or rectangular shape, which is smaller than the stage 10. The pressing pad 34 is formed into a circular or rectangular shape by a material (for example, rubber) that is softer than the pad frame 33, and the outer edge portion 34B of the pressing pad 34 is surrounded and supported by the pad frame 33. Therefore, the central portion 34A of the pressing pad 34 hangs down to a position below the outer edge portion 34B by its own weight, and the sheet 3 is pressed by the central portion 34A and the glass stage 12 to hold the sheet 3. It is preferable that the pressing pad 34 is formed smaller than the glass stage 12.

[0031] The resin supply unit 40 includes: a supply nozzle 41, which is arranged on the carrier 10 (sheet 3); and a pump (not shown) that transports the liquid resin 42 to the supply nozzle 41, and supplies (drops) a predetermined amount of the liquid resin 42 from the supply nozzle 41 to the center of the upper surface of the sheet 3. In addition, the resin supply unit 40 may have a supply nozzle 41 that allows the supply nozzle 41 to Figure 1 The moving mechanism shown moves between a supply position on the stage 10 and a retreat position horizontally or upwardly away from the stage 10. Liquid resin 42 is used as a protective member for protecting the lower surface (first surface) 1B of the wafer 1, and for example, ultraviolet curing resin is used.

[0032] The wafer transfer unit 50 includes: a unit body 51 extending in the horizontal direction; a holding portion 52 provided on the lower surface of the unit body 51 to hold the wafer 1; a lifting unit 53 to lift the unit body 51 relative to the stage 10; and a horizontal moving mechanism (not shown) to move the lifting unit 53 in the horizontal direction. The horizontal moving mechanism moves the unit body 51 supported by the lifting unit 53 between the transfer position on the stage 10 and the distance therefrom. Figure 1 The holding portion 52 is made of porous ceramics, for example, and the upper surface (other surface) 1A of the wafer 1 is held on the lower surface 52A (holding surface) of the holding portion 52 by negative pressure from a vacuum suction source (not shown).

[0033] The control unit 60 includes, for example, a CPU and a processing unit, ROM, RAM, etc., and is mainly composed of a microprocessor that manages the overall control of the protective member forming device 100. The control unit 60 is connected to the stage 10, the sheet conveying device 20, the sheet pressing unit 30, the resin supply unit 40, and the wafer conveying unit 50, which are the components of the protective member forming device 100. The microprocessor of the control unit 60 controls various operations such as sheet conveying, supply of liquid resin, or conveyance of wafers.

[0034] Next, the operation of the protection member forming apparatus 100 will be described. Figure 4 It is a schematic diagram showing the operation of placing a sheet on the stage. Figure 5 Schematic diagram showing the operation of performing wrinkle removal of the sheet. Figure 6 Schematic diagram showing a sheet placed on a stage after wrinkle removal has been performed. Figure 7 Schematic diagram showing the operation of supplying liquid resin onto a chip. Figure 8 It is a schematic diagram showing the operation of transferring a wafer onto liquid resin. Fig. 9 This is a schematic diagram showing the operation of hardening the liquid resin to form a wafer protection member.

[0035] [Film transport operation]

[0036] First, the sheet transport device 20 transports the sheet 3 onto the stage 10. The sheet transport device 20 is controlled by the control unit 60. Figure 1 As shown in the figure, the sheet 3 is held by the suction pad 22, and the horizontal moving mechanism (not shown) is operated to transport the transfer arm 21 (sheet 3) to the top of the stage 10. Then, the sheet transport device 20 lowers the transfer arm 21 by the operation of the lifting unit 23, and releases the suction of the suction pad 22. Figure 4 As shown in FIG. 1 , the sheet 3 is placed on the stage 10. In this case, the sheet 3 is placed on the stage 10. Figure 3 As shown in the figure, the sheet 3 is placed on the stage 10 so as to cover the plurality of air supply ports 14 formed on the stage body 11. When the sheet 3 is placed on the stage 10, the sheet conveying device 20 is retracted from the stage 10. In addition, when the sheet 3 is placed on the stage 10, the sheet 3 may be slightly wrinkled. When resin is supplied to the sheet 3 in the wrinkled state, the thickness of the resin on the sheet 3 will vary, so the sheet 3 is wrinkled.

[0037] [Wrinkle removal action of the film]

[0038] The wrinkle removal of the sheet 3 is performed using the sheet pressing unit 30. The sheet pressing unit 30 is controlled by the control unit 60 as follows. Figure 5 As shown in the figure, the horizontal moving mechanism (not shown) is operated to transport the pressing pad 34 to the upper side of the sheet 3 placed on the stage 10. Then, the sheet pressing unit 30 lowers the pressing pad 34 by the operation of the lifting unit 35. Thus, the central portion 34A of the pressing pad 34 contacts at least a portion of the region 3A of the sheet 3 located on the inner side of the plurality of air supply ports 14.

[0039] On the other hand, the carrier 10 activates the air supply source 16 through the control unit 60, and sprays air from the air supply ports 14. The air contacts the sheet 3, flows toward the outer periphery of the sheet 3, and is discharged from between the sheet 3 and the carrier 10. As a result, the area of ​​the sheet 3 that is not in contact with the pressing pad 34 (particularly the area 3B that is further outward than the air supply port 14) is lifted up from the carrier 10 due to the flow of air, and slides radially on the carrier 10. In particular, in the present embodiment, a fluororesin-based coating process is applied to the upper surface 11A of the carrier body 11, so that the area 3B on the outer side of the sheet 3 slides well toward the outside on the upper surface 11A of the carrier body 11. Therefore, in a state where the central portion of the sheet 3 is pressed, the outer periphery of the sheet 3 slides outward by the supply of air, so that the wrinkles of the sheet 3 can be easily and effectively stretched. Therefore, as Figure 6 As shown, the sheet 3 can be placed on the stage 10 without wrinkling the sheet 3 .

[0040] [Resin provides action]

[0041] Then, if Figure 7 As shown in FIG. 1 , a supply nozzle 41 of a resin supply unit 40 is arranged above the center of the stage 10 (chip 3), and a liquid resin 42 is supplied from the supply nozzle 41 to the chip 3. When a predetermined amount of the liquid resin 42 is accumulated on the chip 3, the supply (dropping) of the liquid resin 42 from the supply nozzle 41 to the chip 3 is stopped. The thickness of the portion that becomes the protective member by curing the liquid resin 42 is the same as that of the wafer 1 ( Figure 1 ) area and calculate the amount of liquid resin 42 provided to the sheet 3.

[0042] [Expansion action of liquid resin]

[0043] Next, the liquid resin supplied to the wafer 3 is spread. In the present embodiment, the liquid resin is spread by using a wafer transfer unit 50 that holds the wafer (original sliced ​​wafer) 1 and transfers it to the stage 10. Specifically, the wafer transfer unit 50 operates a horizontal moving mechanism (not shown) such as Figure 8 After the position in the plane direction of the center of the stage 10 is made to coincide with the position in the plane direction of the center of the wafer 1 held by the lower surface 52A of the holding portion 52, the unit main body 51 is lowered in a direction approaching the stage 10 by the lifting unit 53. When the unit main body 51 is lowered, the lower surface 52A holding the wafer 1 and the sheet 3 on the stage 10 come close to each other and press the liquid resin 42, so that the liquid resin 42 between the wafer 1 and the sheet 3 spreads in the radial direction of the wafer 1. Therefore, the liquid resin 42 is spread over the entire lower surface 1B of the wafer 1.

[0044] In addition, in the present embodiment, the wafer transfer unit 50 that transfers the wafer 1 directly lowers the wafer 1 to press the liquid resin 42 and spread it, but it may also be configured to have a pressing unit (not shown) that moves the wafer 1 toward the sheet 3 and presses the liquid resin 42 after the wafer 1 is transferred onto the liquid resin 42. That is, as long as the wafer 1 located on the sheet 3 is pressed toward the sheet 3 via the liquid resin 42, any means of pressing the wafer 1 may be used.

[0045] [Resin curing behavior]

[0046] After the liquid resin has been expanded, Fig. 9As shown, the plurality of UV (ultraviolet) lamps 13 disposed in the stage body 11 are turned on to irradiate the ultraviolet light 13A toward the liquid resin 42. The liquid resin 42 is hardened by the stimulation of the ultraviolet light 13A, thereby forming a protective member 43 that protects the entire lower surface 1B of the wafer 1. Next, the holding portion 52 releases the suction holding of the wafer 1, and the unit body 51 is raised by the lifting unit 53, so that the holding portion 52 is separated from the wafer 1.

[0047] Then, for example, by using a grinding tool, the upper surface 1A side of the wafer 1 located on the side opposite to the side provided with the protective member 43 is ground, and then after the protective member 43 is peeled off, the ground upper surface 1A side is held and the lower surface 1B of the wafer 1 is ground. In this way, the undulation or warping of the wafer 1 can be removed to form a flat wafer 1.

[0048] As described above, the protective component forming device 100 of the present embodiment for forming a protective component 43 on the lower surface (first surface) 1B of the chip 1 is constructed to include: a carrier 10, which carries the chip 3 and has a glass table 12 surrounded by a carrier body 11; a plurality of air supply ports 14, which are formed in the carrier body 11 and connected to the air supply source 16; a movable chip transfer unit 50, which faces the carrier 10 and holds the chip 1; a resin supply unit 40, which supplies liquid resin onto the chip 3; and a pressing pad 34, which is supported to be movable in the up and down directions at a position facing the chip 3, and the pressing pad 34 contacts at least a portion of the area 3A of the chip 3 carried on the carrier 10 and covering the plurality of air supply ports 14 in the area 3A closer to the inside than the plurality of air supply ports 14, thereby pressing the chip 3. According to this structure, air is supplied from the air supply port 14, so that the area 3B of the sheet 3 not in contact with the pressing pad 34 floats from the stage 10 and slides in the outer peripheral direction, thereby stretching the wrinkles of the sheet 3. Therefore, the sheet 3 can be placed on the stage 10 without wrinkling.

[0049] According to the present embodiment, the upper surface 11A of the stage body 11 is coated with fluororesin, so that the outer periphery of the sheet 3 slides outward by supplying air while the center of the sheet 3 is pressed, thereby making it possible to easily and effectively stretch the wrinkles of the sheet 3.

[0050] In addition, the present invention is not limited to the above-mentioned embodiment. That is, various modifications can be made and implemented within the scope of the main purpose of the present invention. The protective component forming device of the above-mentioned embodiment can be used not only for a structure in which a resin is applied to the first surface of a wafer to form a protective component in order to remove the undulation or warping generated on the cut wafer, but also, for example, can be used for a structure in which a resin is applied to the front surface to form a protective component when grinding a wafer having bumps and other concave and convex parts on the front surface (first surface), and then the back surface (the other surface) of the wafer is ground.

Claims

1. A protective member forming device, which forms a protective member on a first surface of a wafer having a first surface and a second surface opposite to the first surface, wherein: The protective component forming device comprises: A carrier for placing a sheet, comprising a chuck table surrounded by a frame, wherein a plurality of air supply ports respectively connected to air supply sources are formed in the frame; A movable holding unit facing the stage and holding the wafer; a resin supplying unit that supplies resin onto the sheet; a sheet pressing pad supported so as to be movable in the up-down direction at a position facing the sheet; and a control unit that controls the actions of the holding unit, the resin supply unit, and the sheet pressing pad, The control unit controls as follows: air is supplied from the air supply source while the sheet pressing pad is in contact with the central portion of the sheet placed on the carrier, so that the area of ​​the sheet not in contact with the sheet pressing pad floats from the carrier and slides toward the periphery, thereby stretching the wrinkles of the sheet.

2. The protective member forming device according to claim 1, wherein: The frame of the carrier is coated with fluororesin.

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