Chuck table

Abstract

To provide a chuck table that can be easily released even when an adherend is sucked and held via a dicing tape.SOLUTION: A chuck table 2 includes: a porous chuck 21 on which an adherend W is placed via a dicing tape DT; a chuck base 22 that accommodates the porous chuck 21 on its upper surface; a first supply port 23 provided at an approximate center of the chuck base 22; a second supply port 24 provided in the chuck base 22 so as to surround the first supply port 23 in a central part of the chuck base 22; and a supply source for supplying negative pressure or compressed air to the porous chuck 21 via the first supply port 23 and the second supply port 24.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a chuck table capable of suction-holding an adherend attached to a dicing frame via a dicing tape. [Background technology]

[0002] In the field of semiconductor manufacturing, there is a process of grinding the backside of a semiconductor substrate such as a silicon wafer (hereinafter referred to as the "adherend") to make it thinner, and in this process, a protective sheet made of an adhesive film or the like is attached to the surface of the adherend to protect the devices formed on the surface of the adherend.

[0003] Patent Document 1 discloses an apparatus in which a wafer W mounted on a dicing tape DT is placed on a table T, a peeling tape PT is melt-bonded to an adhesive sheet S, and the table T and a chuck 32 that holds the peeling tape PT move relative to each other, thereby peeling the adhesive sheet S from the wafer W. The reference numerals used are those in Patent Document 1. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2009-253084 Summary of the Invention [Problem to be solved by the invention]

[0005] However, wafers W and peeling tapes PT tend to become thinner, and in a sheet peeling device such as that described in Patent Document 1, the dicing tape DT tends to be difficult to peel from the upper surface (adsorption surface) of the table T. If transport of the wafer W begins before the entire surface of the dicing tape DT is peeled from the upper surface (adsorption surface) of the table T, there is a risk that the wafer W will be damaged.

[0006] Therefore, a technical problem arises that must be solved in order to provide a chuck table that can be easily released even when the adherend is held by suction via dicing tape, and the present invention aims to solve this problem. [Means for solving the problem]

[0007] In order to achieve the above object, a chuck table according to the present invention includes a porous chuck on which an adherend is placed via a dicing tape, a chuck base that accommodates the porous chuck on its upper surface, and a chuck base Inside center portion a first supply port provided in the chuck base; The aforementioned a plurality of second supply ports provided in the chuck base so as to surround the first supply port at a central portion; a supply source that supplies negative pressure or compressed air toward the porous chuck via the first supply port and the plurality of second supply ports; a first adjustment mechanism that adjusts the pressure and flow rate of the compressed air supplied from the supply source to the first supply ports; and a second adjustment mechanism that adjusts the pressure and flow rate of the compressed air supplied from the supply source to the plurality of second supply ports, the first supply port is formed to have a larger diameter than the second supply port, The first adjustment mechanism and the second adjustment mechanism adjust the pressure and flow rate of the compressed air, respectively, so as to push the dicing tape out of the porous chuck.

[0008] According to this configuration, compressed air discharged from the first supply port and the second supply port is supplied through the porous chuck between the surface of the porous chuck and the dicing tape, so that the dicing tape that has entered the fine pores of the porous chuck near the first supply port and the second supply port is pushed out of the pores, and the compressed air discharged from the first supply port collides with the compressed air discharged from the second supply port and remains on the radially inner side of the chuck table, allowing the dicing tape to be efficiently peeled off near the center of the porous chuck.

[0009] The chuck table according to the present invention further comprises: 2The pressure of the compressed air discharged from the supply port of 1 It is preferable that the pressure is set higher than the pressure of the compressed air discharged from the supply port.

[0010] With this configuration, the compressed air discharged from the first supply port tends to remain on the radially inner side of the chuck table, being blocked by the compressed air discharged from the second supply port, thereby efficiently releasing the suction between the dicing tape and the porous chuck.

[0011] In addition, the chuck table according to the present invention is configured such that the pressure of the compressed air discharged from the first supply port and the pressure of the compressed air discharged from the second supply port are equal to each other. , etc. It is preferable that the setting is properly done.

[0012] According to this configuration, the suction between the dicing tape and the porous chuck can be released without applying excessive pressure to the adherend. [Effects of the Invention]

[0013] The present invention makes it possible to easily release the adherend from the porous chuck even when the adherend is held by suction via a dicing tape. [Brief explanation of the drawings]

[0014] [Figure 1] 1 is a perspective view showing a sheet peeling device to which a chuck table according to an embodiment of the present invention is applied; [Figure 2] FIG. [Figure 3] 3A and 3B are a plan view and a longitudinal sectional view showing a chuck table; [Figure 4] FIG. 2 is a schematic diagram showing how an adherend is peeled off from a chuck table. [Figure 5] FIG. 10 is a schematic diagram showing how an adherend is peeled off in a chuck table according to a comparative example. DETAILED DESCRIPTION OF THE INVENTION

[0015] The present invention will be described below with reference to the drawings. When referring to the number, numerical value, amount, range, etc. of components, unless otherwise specified or when the number is clearly limited to a specific number in principle, the number is not limited to the specific number, and may be greater than or less than the specific number.

[0016] Furthermore, when referring to the shape or positional relationship of components, etc., it includes things that are substantially similar or approximate to those shapes, etc., unless otherwise specified or when it is clearly considered otherwise in principle.

[0017] In addition, the drawings may exaggerate characteristic parts to make the features easier to understand, and the dimensional ratios of the components may not be the same as in reality.

[0018] Fig. 1 is a perspective view of the sheet peeling apparatus 1. Fig. 2 is a side view of the sheet peeling apparatus 1. The sheet peeling apparatus 1 peels off a protective sheet S (BG tape) that is adhered to an adherend W to protect the surface of the adherend W when grinding the backside of the adherend W. The adherend W is, for example, a semiconductor substrate such as a silicon wafer, but is not limited to this.

[0019] The adherend W is mounted on the ring frame RF via the dicing tape DT with the protective sheet S facing up. The dicing tape DT is an ultraviolet curing tape or the like.

[0020] The sheet peeling device 1 includes a chuck table 2 on which an adherend W is placed. As shown in FIG.

[0021] The porous chuck 21 is an adsorption body made of a porous material having numerous pores therein. The roughness of the pores of the porous chuck 21 is, for example, #400 or #800.

[0022] The chuck base 22 accommodates the porous chuck 21 on its upper surface. The chuck base 22 has one first supply port 23 and eight second supply ports 24 formed therein.

[0023] The first supply port 23 opens on the upper surface of the chuck base 22 and is formed approximately in the center of the chuck base 22. The first supply port 23 is formed to have a slightly larger diameter than the second supply port 24.

[0024] The second supply ports 24 open to the upper surface of the chuck base 22 and are arranged substantially concentrically and at equal intervals to surround the first supply port 23. The numbers of the first supply ports 23 and the second supply ports 24 are not limited to those described above.

[0025] The first supply port 23 and the second supply port 24 are switchably connected to a vacuum source S1 and a compressed air source S2. When the vacuum source S1 is activated, a negative pressure is supplied between the adherend W placed on the porous chuck 21 and the upper surface (the suction surface 21a) of the porous chuck 21, and the adherend W is suction-held on the suction surface 21a. When the compressed air source S2 is activated, compressed air (release air) is supplied between the adherend W and the suction surface 21a, and the suction between the adherend W and the suction surface 21a is released. Note that reference numerals 25 and 26 denote needle valves. The pressure of the release air can be adjusted by adjusting the opening of the needle valves 25 and 26. The pressure of the release air is set to, for example, 0.2 MPa.

[0026] The chuck table 2 is provided so as to be movable in a sliding direction (from right to left on the paper surface of FIG. 2) via a moving means (not shown).

[0027] Further, near the chuck table 2, a transport hand 27 is provided which is capable of gripping the dicing frame DF and transporting the adherend W.

[0028] The sheet peeling device 1 includes a feeding means 3 capable of feeding out a strip-shaped peeling tape T. The feeding means 3 includes a feed roller 31, a take-up roller 32, first to fourth guide rollers 33 to 36, and a pressing member 37.

[0029] The feed roller 31 supports the strip-shaped release tape T so that it can be fed out. The take-up roller 32 applies a feeding force to the release tape T and winds it up. The first to fourth guide rollers 33 to 36 and the pressing member 37 are arranged at appropriate positions so as to apply tension to the release tape T and to regulate the trajectory of the release tape T.

[0030] The sheet peeling device 1 is provided with a heat stamp 4 as an adhering means for adhering the peeling tape T to the protective sheet S. The heat stamp 4 is provided with a cylinder (not shown) for raising and lowering the heat stamp 4 up and down.

[0031] The heat stamp 4 includes a first head 41 and a second head 42. The first head 41 and the second head 42 are arranged side by side in this order from the front to the rear in the sliding direction with a small gap between them. The first head 41 and the second head 42 are heated to a predetermined temperature and pressed against the peeling tape T, thereby welding the peeling tape T and the protective sheet S together.

[0032] The first head 41 is disposed so that the lower surface 43 faces the periphery of the adherend W. The lower surface 43 is formed in a sectorial ring shape having approximately the same diameter as the radius of the protective sheet S when viewed from the bottom.

[0033] The lower surface 44 of the second head 42 is formed to have a larger area than the lower surface 43. Specifically, the lower surface 44 is formed to be wider than the lower surface 43 in both the sliding direction and the width direction perpendicular to the sliding direction (the direction perpendicular to the paper surface of FIG. 2).

[0034] It goes without saying that the shapes of the first head 41 and the second head 42 are not limited to those described above. Furthermore, the first head 41 and the second head 42 are not limited to being provided on a single heat stamp, and may be provided on two independent heat stamps. Furthermore, the number of heads that adhere the peeling tape T and the protective sheet S may be three or more.

[0035] The sheet peeling device 1 is equipped with a regulating roller 5 as a regulating means. The regulating roller 5 is disposed approximately 2 to 3 mm above the position where peeling of the protective sheet S begins (peeling start position). The length of the regulating roller 5 is set to be greater than the diameter of the adherend W. The regulating roller 5 is provided rotatably around a support shaft (not shown) that is mounted approximately horizontally so that the peeling tape T can be smoothly fed out.

[0036] To prevent the peeling tape T from accidentally adhering to the surface (guide surface 51) of the regulating roller 5, it is preferable to coat the guide surface 51 with fluororesin or to knurl the guide surface 51. This allows the peeling tape T to be fed out smoothly.

[0037] The regulating means is not limited to the above-described form, and may be, for example, a fan-shaped pillar with a smooth arc-shaped guide surface that restricts the bending direction of the peeling tape T by holding it down.

[0038] Furthermore, if the guide surface is smooth and the peeling tape T can be smoothly dispensed, the tape may be configured to be non-rotatable around the support shaft and the peeling tape T may be configured to slide on the guide surface 51.

[0039] The operation of the sheet peeling device 1 is controlled via a controller (not shown). The controller controls each of the components that make up the sheet peeling device 1. The controller is, for example, a computer, and is composed of a CPU, memory, etc. The functions of the controller may be realized by control using software, or may be realized by something that operates using hardware.

[0040] Next, the operation of the sheet peeling device 1 will be described.

[0041] [Substrate chuck] First, the transfer hand 27 grips the dicing frame DF and places the adherend W having a thickness of about 20 μm and a diameter of about 400 mm on the porous chuck 21.

[0042] Next, as shown in Figure 4(a), needle valves 25 and 26 are opened, and negative pressure is supplied between the dicing tape DT and the adsorption surface 21a via the first supply port 23, the second supply port 24 and the inside of the porous chuck 21, and the adherend W is adsorbed to the chuck table 2 via the dicing tape DT.

[0043] [Sheet peeling] First, the chuck table 2 is moved so that the outer periphery of the adherend W is positioned below the heat stamp 4.

[0044] Next, the cylinder is driven to lower the heat stamp 4, and the first head 41 and the second head 42 come into contact with the peel tape T and heat and press it at a stamp temperature of 180°C, thereby welding the peel tape T to the outer periphery of the protective sheet S.

[0045] The welding ranges of the first head 41 and the second head 42 are set according to the shapes of the lower surfaces 43, 44, and the welding range of the second head 42 is formed to be larger than the welding range of the first head 41. The position on the protective sheet S where the peeling tape T is welded by the first head 41 becomes the peel start position of the protective sheet S.

[0046] Next, the cylinder is driven to raise the heat stamp 4, and then the chuck table 2 is moved (towards the left side of the paper in FIG. 2) so that the peeling start position approaches the regulating roller 5. The peeling tape T is bent in a generally horizontal U-shape when viewed from the side, bulging forward from the peeling start position in the direction in which the chuck table 2 moves.

[0047] When the chuck table 2 is moved further, the regulating roller 5 comes into contact with the peeling tape T and holds down the deflection of the peeling tape T in an approximately vertical direction. In this state, the tension acting on the peeling tape T causes a peeling force to act on the protective sheet S to peel the protective sheet S from the adherend W, and the protective sheet S begins to peel off from the adherend W.

[0048] In this way, the regulating roller 5 holds down the deflection of the peeling tape T in an approximately vertical direction, thereby reducing the vertical component of the peeling force acting on the protective sheet S, preventing the adherend W from bouncing up in response to the protective sheet S, and allowing the protective sheet S to be peeled off without damaging the adherend W.

[0049] After the protective sheet S attached to the outer periphery of the adherend W has been completely peeled off, the chuck table 2 is further moved to peel off the entire surface of the protective sheet S from the adherend W.

[0050] [Substrate release] In order to transport the adherend W from which the protective sheet S has been peeled off to another device, release air A is supplied between the porous chuck 21 and the dicing tape DT to release the vacuum suction between the adherend W and the chuck table 2.

[0051] However, the underside of the dicing tape DT penetrates into the minute pores of the porous chuck 21, and the dicing tape DT is held in close contact with the porous chuck 21. If the supply area of ​​the release air A is significantly narrow compared to the surface area of ​​the dicing tape DT, for example, as shown in Figure 5(a), if the chuck table 2 is not provided with a first supply port 23 and release air A is discharged only from the second supply port 24, the underside of the dicing tape DT will not peel off from the minute pores of the porous chuck 21 near the center of the porous chuck 21, and as shown in Figure 5(b), there is a risk that the suction between the dicing tape DT and the suction surface 21a will not be released.

[0052] It is also possible to increase the pressure of the release air A from the second supply port 24 to peel off the entire surface of the dicing tape DT, but there is a risk that the thin adherend W may crack due to excessively high pressure.

[0053] On the other hand, as shown in FIG. 4(b), by supplying release air A from two different points in the radial direction of the chuck table 2, the suction between the dicing tape DT and the suction surface 21a can be released.

[0054] That is, as shown in Figure 4(c), release air A discharged from the first supply port 23 and supplied through the porous chuck 21 pushes the dicing tape DT that has entered the fine pores of the porous chuck 21 out of the porous chuck 21 near the first supply port 23, and release air A discharged from the second supply port 24 and supplied through the porous chuck 21 pushes the dicing tape DT that has entered the fine pores of the porous chuck 21 out of the porous chuck 21 near the second supply port 24.

[0055] Furthermore, as shown in Figure 4(d), the release air A ejected from the first supply port 23 and the second supply port 24 spreads horizontally over the suction surface 21a, peeling off the dicing tape DT that has entered the fine pores of the porous chuck 21 over a wide area from the suction surface 21a, thereby releasing the suction between the dicing tape DT and the suction surface 21a.

[0056] In particular, the release air A discharged from the first supply port 23 collides with the release air A discharged from the second supply port 24 and remains on the radially inner side of the chuck table 2, thereby enabling the dicing tape DT near the center of the porous chuck 21 to be efficiently peeled off.

[0057] Furthermore, if the pressure of the release air A discharged from the second supply port 24 is set higher than the pressure of the release air A discharged from the first supply port 23, the release air A discharged from the first supply port 23 tends to remain on the inner side of the chuck table 2, as if being blocked by the release air A discharged from the second supply port 24, and the adsorption between the dicing tape DT and the adsorption surface 21a can be released more efficiently.

[0058] Furthermore, when the pressure of the release air A discharged from the first supply port 23 and the pressure of the release air A discharged from the second supply port 24 are set to be approximately equal, the adsorption between the dicing tape DT and the adsorption surface 21a can be released without excessive pressure acting on the adherend W and damaging it.

[0059] It is preferable that the release air A be set to a low pressure within a range that allows the dicing frame DF to be peeled off.

[0060] Then, when the entire surface of the dicing tape DT is peeled off from the suction surface 21a, the transport hand 28 grips the dicing frame DF and transports the adherend W.

[0061] In this way, in the sheet peeling device 1 of this embodiment, the release air A ejected from the first supply port 23 and the second supply port 24 is supplied between the suction surface 21a and the dicing tape DT through the porous chuck 21, so that the dicing tape DT that has entered the fine pores of the porous chuck 21 near the first supply port 23 and the second supply port 24 is pushed out of the pores, and the release air A ejected from the first supply port 23 collides with the release air A ejected from the second supply port 24 and remains on the radially inner side of the chuck table 2, so that the dicing tape DT can be efficiently peeled off near the center of the porous chuck 21.

[0062] An example of the chuck table will be described below. [1] A chuck table capable of suction-holding an adherend attached to a dicing tape stretched over a dicing frame, comprising: a porous chuck on which the adherend is placed via the dicing tape; a chuck base on which the porous chuck is housed; supply ports provided at a plurality of different points in the radial direction of the chuck base; a supply source that supplies negative pressure or compressed air toward the porous chuck through the supply ports; and a plurality of pressure adjusting devices that adjust the pressure and flow rate of the compressed air supplied from the supply source for each of the supply ports provided at a plurality of different points in the radial direction. and an adjustment mechanism, wherein the supply port provided in the center of the chuck base among the plurality of supply ports is formed with a larger diameter than the other supply ports, and the other supply ports are provided only in the central portion of the porous chuck, the supply source supplies the compressed air set to a low pressure within a range capable of peeling the dicing tape from the porous chuck, and the adjustment mechanism adjusts the pressure of the compressed air supplied from the supply source to the supply port so as to push out the dicing tape that has entered the pores of the porous chuck around the supply port to the outside of the porous chuck.

[0063] According to this configuration, compressed air discharged from different supply ports is supplied through the porous chuck between the surface of the porous chuck and the dicing tape, so that the dicing tape that has entered the fine pores of the porous chuck near each supply port is pushed out of the pores, and the compressed air discharged from the supply port provided on the radially inner side of the chuck base collides with the compressed air discharged from the supply port provided on the radially outer side and remains on the radially inner side of the chuck table, allowing the dicing tape to be efficiently peeled off over a wide area.

[0064] Furthermore, the present invention can be modified in various ways other than those described above without departing from the spirit of the present invention, and it goes without saying that the present invention also covers such modifications.

[0065] For example, in the above-described embodiment, the first supply port 23 and the second supply port 24 are provided at two different points in the radial direction of the chuck table, but the supply ports for ejecting the release air A may be provided at three or more points along the radial direction of the chuck table. [Explanation of symbols]

[0066] 1: Sheet peeling device 2: Chuck table 21:Porous chuck 21a: Adsorption surface 22: Chuck base 23: First supply port 24: Second supply port 25, 26: Needle valve 27, 28: Transfer hand 3: Feeding means 31: Feed roller 32: Winding roller 33: Fourth guide roller 34: Fourth guide roller 35: 4th guide roller 36: 4th guide roller 37: Pressing member 4: Heat stamping 41: First Head 42: Second Head 43: Underside (of first head) 44: Underside (of second head) 5: Regulating roller 51: Guide surface A: Release air DF: Dicing frame DT: Dicing tape PT: Peeling tape RF: Ring frame S: Protective sheet S1: Vacuum source (supply source) S2: Compressed air source (supply source) T: Peeling tape W: Adherent

Claims

1. a porous chuck on which an adherend is placed via a dicing tape; a chuck base that accommodates the porous chuck on its upper surface; a first supply port provided in a central portion of the chuck base; a plurality of second supply ports provided in the chuck base so as to surround the first supply port in the central portion of the chuck base; a supply source that supplies negative pressure or compressed air toward the porous chuck through the first supply port and the plurality of second supply ports; a first adjusting mechanism that adjusts the pressure and flow rate of the compressed air supplied from the supply source to the first supply port; a second adjusting mechanism that adjusts the pressure and flow rate of the compressed air supplied from the supply source to the second supply ports; Equipped with the first supply port is formed to have a larger diameter than the second supply port, The chuck table is characterized in that the first adjustment mechanism and the second adjustment mechanism adjust the pressure and flow rate of the compressed air, respectively, so as to push the dicing tape out of the porous chuck.

2. 2. The chuck table according to claim 1, wherein the pressure of the compressed air discharged from the second supply port is set higher than the pressure of the compressed air discharged from the first supply port.

3. 2. The chuck table according to claim 1, wherein the pressure of the compressed air discharged from said first supply port and the pressure of the compressed air discharged from said second supply port are set equal to each other.

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