JP2004281867A - Protective tape sticking method and sticking apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a protective tape sticking method and sticking apparatus capable of neatly sticking a protective tape to the surface of a semiconductor wafer slightly inwardly from its outer circumferential edge to thereby surely protect the wafer surface. <P>SOLUTION: The protective tape sticking apparatus includes: a mask member 22 acting like a tool that is located at the outside of the outer circumferential edge of the semiconductor wafer surface 12a and has a step located slightly above the wafer surface 12a slightly inwardly from the outer circumferential edge nearly along the outer circumferential; a protective tape positioning means for positioning the protective tape 14, whereby the entire wafer surface 12a is to be covered, so as to cover the step of the mask member 22 and the wafer surface 12a; a cutter 58 whose edge of blade is placed between the wafer surface 12a and the step of the mask member 22; a cutter unit 50 for rotating the cutter 58 along the outer circumferential edge slightly inwardly from the outer circumferential edge of the wafer surface 12a; and a soft pressing roller 24 for sticking fast the protective tape 14 stuck to the wafer surface 12a. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a protective tape attaching method and an attaching device for attaching a protective tape to a surface of a semiconductor wafer having a surface on which a predetermined circuit pattern or the like has been formed and cutting out the semiconductor wafer along an outer peripheral shape.
[0002]
[Prior art]
[Patent Document 1] Japanese Patent Application Laid-Open No. 2002-57208 [Patent Document 2] Japanese Patent Application Laid-Open No. 2001-148412 Conventionally, a semiconductor wafer (hereinafter simply abbreviated as a wafer) on which a pattern forming process of a predetermined circuit or element has been performed. When the back surface is polished (back-ground) or etched, an adhesive protective tape is attached to the wafer surface to protect the wafer surface. The front side of the wafer protected by the protective tape is suction-held by a suction cup, and the back side is subjected to processing such as polishing. The method of attaching this protective tape to the surface of the wafer is such that after attaching a protective tape wider than the outer shape of the wafer to the entire surface, the protective tape is cut out along the outer peripheral edge of the wafer so that the protective tape does not protrude around. . As shown in FIG. 9, the cutout is performed by cutting the protective tape 4 stuck on the surface 2a of the wafer 2 with a cutter 6 inclined slightly toward the wafer 2 from the right angle to the wafer surface 2a. The cutter 6 is lightly applied to the wafer end face 2b so as to form a shape equal to the outer shape of the wafer along the peripheral edge, thereby cutting the wafer.
[0003]
[Problems to be solved by the invention]
Here, the corner of the outer peripheral edge of the front surface side of the wafer 2 is a rounded R shape, and as shown in FIG. 9, the cut edge of the protective tape 4 attached to the wafer surface 2a is the outer peripheral edge of the wafer 2. It is in a state of being slightly curved along the corner R of the section. On the other hand, in recent years, the thickness of the wafer has been reduced from the conventional 100 to 150 μm to about 50 μm in order to reduce the thickness of the semiconductor element and the like, and the polishing allowance t on the back surface of the wafer has increased. In such a case, there is a possibility that the polishing from the back side may reach the R portion of the corner on the front surface 2a side by the polishing on the back side, and the grindstone for the back grinding comes into contact with the protection tape 4 and entrains the protection tape 4, This resulted in poor polishing and the like. Further, since the outer peripheral edge of the protective tape 4 protrudes from the outer peripheral edge of the wafer 2, polishing scraps generated during polishing are accumulated in the gap between the protruding edge of the protective tape 4 and the corner R. In addition, there is a possibility that these polishing dusts have an adverse effect in a subsequent process. If the cut edge of the protective tape 4 attached to the wafer surface 2a is the same as or slightly protrudes from the outer peripheral edge of the wafer 2, the cut edge of the protective tape 4 is located at the corner R on the wafer surface 2a side. There is a portion that is not in close contact, and the protective tape 4 is easily peeled off from that portion, and the polishing liquid or the etching liquid enters the inside of the protective tape 4 from the interface between the peripheral edge of the wafer 2 and the protective tape 4. Therefore, there is a problem that the circuit elements in the wafer 2 and a part of the formation area thereof are contaminated or damaged.
[0004]
SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the related art, and it is possible to cleanly attach a protective tape to a surface slightly inside the outer peripheral edge of a semiconductor wafer, thereby reliably protecting the wafer surface. It is an object of the present invention to provide a protective tape sticking method and a sticking device which can perform the method.
[0005]
[Means for Solving the Problems]
According to the present invention, a jig having a step located outside the outer peripheral edge of the surface of the semiconductor wafer and substantially slightly above the outer surface of the wafer along the outer peripheral edge is provided to cover the wafer surface. The protective tape was affixed to the jig so that the protective tape would cover the step of the jig, the entire surface of the wafer was covered with the protective tape, and the protective tape was stuck to the surface of the wafer and the step of the jig. A method of attaching a protective tape, wherein the protective tape is cut at a position slightly inside the outer peripheral edge of the wafer along the step. Further, the protective tape, which is attached to the surface of the wafer and cut off inside the outer peripheral edge of the wafer, is pressed against the surface of the wafer by a soft pressing roller so as to be brought into close contact therewith. Also, after attaching the protective tape to the jig, a cut is made at a position along the orientation flat portion of the wafer, and then a cutter whose blade rotates at a position slightly inside the outer peripheral edge of the wafer, The protective tape is cut off.
[0006]
The present invention also provides a jig having a step located outside the outer peripheral edge of the semiconductor wafer surface and located slightly above the wafer surface along the outer peripheral edge and slightly above the outer peripheral edge; Protective tape positioning means for positioning the protective tape covering the step on the jig and the surface of the wafer, a cutter having a cutting edge positioned between the wafer surface and the step of the jig, and the cutter And a driving device for rotating the wafer along the outer peripheral edge slightly inside the outer peripheral edge of the wafer surface. Furthermore, a soft pressing roller is provided in which the protective tape attached to the wafer surface is pressed against the surface of the wafer to make close contact therewith.
[0007]
The jig is a mask member having an opening surrounding an outer peripheral edge of the wafer. Alternatively, the jig may be a base on which a recess for positioning the wafer is formed, or a base on which an opening for positioning the wafer is formed.
[0008]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. 1 to 5 show a first embodiment of a protective tape applying apparatus according to the present invention. This protective tape applying apparatus 10 is used for a wafer 12 on which a pattern forming process of a predetermined circuit or element has been performed. Then, a protective tape 14 made of a resin film such as polyolefin is attached to the wafer surface 12a before the back grinding process. The protective tape 14 is provided with an adhesive such as an acrylic adhesive on the back surface, and is provided so as to be able to adhere to the front surface 12 a of the wafer 12. The protective tape 14 is wound into a roll and attached to an unillustrated feeding device, is attached so as to be able to be pulled out, is pulled out and positioned at a predetermined position by unillustrated protective tape positioning means, and the surface 12a of the wafer 12 and the mask It can be attached to the member 22.
[0009]
As shown in FIG. 1, the protective tape attaching device 10 has a base 18 having a concave portion 16 on which the wafer 12 is positioned and placed. The concave portion 16 of the base 18 is substantially equal to the thickness of the wafer 12, and an outer peripheral portion of the concave portion 16 is placed on the base 18 and is concentric with the concave portion 16, and has an opening slightly smaller than the concave portion 16. A mask member 22 having 20 is provided detachably. The mask member 22 is made of, for example, an extremely thin metal plate of 1 mm or less. The base 18 is fixed on a base 25 of the protective tape attaching device 10.
[0010]
Further, the protective tape attaching device 10 is provided with a flexible pressing roller 24 made of silicon rubber or the like. As shown in FIGS. 2 and 3, the pressing roller 24 has a rotation shaft 26 supported by a U-shaped frame member 28, and a center portion of the frame member 28 is attached to an urging device 30. The urging device 30 holds the frame member 28 and presses the frame member 28 against the base 18 by a coil spring 32 or the like. The urging device 30 includes a U-shaped holding frame 31 provided so as to cover the frame member 28, sliders 34 are provided at both ends of the holding frame 31, and provided on the base 25 of the protective tape attaching device 10. Slides on the pair of rails 36 provided. The rails 36 are fixed on both sides of the base 25 in parallel with each other. Guide shafts 38 are provided at both ends of the frame member 28 so as to protrude upward. The guide shafts 38 are fitted to guide members 40 provided on the holding frame 31 of the urging device 30, and the base 18 on which the wafer 12 is placed is mounted. In contrast, the frame member 28 moves up and down while maintaining the horizontal state. The urging means of the urging device 30 may be an air cylinder other than the coil spring 32, as long as it can apply an appropriate pressure.
[0011]
The urging device 30 is provided with a tension roller 42 located above the base 18 and in contact with the back side of the protective tape 14. As the tension roller 42, a coating treatment is performed on the front surface or a non-adhesive roller is used so that the adhesive on the back surface of the protective tape 14 does not easily adhere.
[0012]
Further, the protective tape applying device 10 is provided with a cutter device 50 that can be moved between a retracted position and an operating position on the base 18 by a moving device (not shown). The cutter device 50 includes a rotating arm 52 that rotates concentrically with the recess 16, and a base end of the rotating arm 52 is supported by a rotating shaft 54. A cutter holder 56 is fixed to the other end of the rotating arm 52, and a cutter 58 is attached to the cutter holder 56. As shown in FIG. 1, the cutting edge of the cutter 58 is positioned slightly inside the recess 16, and rotates concentrically inside the opening 20 of the mask member 22. The position of the cutting edge of the cutter 58 is slightly above the surface 12 of the wafer 12 with the wafer 12 placed on the concave portion 16 and closer to the wafer surface 12 a than the upper surface of the opening 20 of the mask member 22. . Further, the cutter 58 may have a blade edge perpendicular to the wafer 12, but may have a blade edge side slightly inclined toward the outer peripheral edge side of the wafer 12 as illustrated. The rotary arm 52 is rotated about a rotary shaft 54 by a drive mechanism (not shown) of the cutter device 50. The angle and position of the cutter 58 can be finely adjusted by an adjustment unit (not shown).
[0013]
In the operation of the protective tape applying apparatus 10 of this embodiment, the protective tape 14 is pulled out from a roll (not shown), inserted under the pressing roller 24, hung above the tension roller 42, and pulled out above the base 18. Then, the wafer 12 is placed in the concave portion 16 of the base 18, and the mask member 22 is positioned and fixed concentrically with the wafer 12. Then, the protective tape 14 is pulled out and positioned on the surface 12a of the wafer 12, and the protective tape 14 is linearly cut along the orientation flat 12b of the wafer 12 at a position slightly inside. Before or after this, the belt-shaped protection tape 14 is attached to the front surface 12 a of the wafer 12 by the pressing roller 24. The pressing roller 24 presses the wafer surface 12a with an appropriate pressure by the urging device 30. Since the pressing roller 24 is made of a flexible material, the pressing roller 24 comes into contact with both the upper surface of the mask member 22 and the surface 12a of the wafer 12, and affixes the protective tape 14. wear. As shown in FIG. 1, the protective tape 14 is also adhered to the surface of the mask member 22, and the step between the opening 12 of the mask member 22 and the wafer 12 is located between the surface of the mask 12 and the surface 12 a of the wafer 12. A space 14a is formed in the space.
[0014]
Thereafter, the pressing roller 22 retracts, the cutter device 50 moves and is positioned, and is positioned concentrically with the wafer 12. Then, the rotating arm 52 is rotated, and the protection tape 14 is cut off slightly inside the outer peripheral edge of the wafer 12 by the cutter 58. At this time, the cutting edge of the cutter 58 is located in the space 14a.
[0015]
Thereafter, the cut outer portion of the protective tape 14 is removed together with the mask member 22, and the cut protective tape 14 is pressed by the pressing roller 24 or another flexible pressing roller so as to be in close contact with the wafer surface 12a. This ensures that the protection tape 14 in the space 14a also closely adheres to the wafer surface 12a, and that no air bubbles remain between the wafer 12 and the protection tape 14. In this state, as shown in FIG. 4 and FIG. 5, the protective tape 14 is adhered to a region slightly inside the surface 12a of the wafer 12 and to the end on the surface 12a side of the R-shaped corner, so that the surface is securely 12a is protected.
[0016]
Thereafter, the wafer 12 on which the protective tape 14 is adhered is subjected to a back grinding process and further processed by etching or the like to a required thickness.
[0017]
According to this embodiment, since the protective tape 14 is stuck slightly inside the outer peripheral edge of the wafer 12, even if the wafer 12 is thinned by the back grinding process, the peripheral edge of the protective tape 14 is There is no contact with the grindstone, and there is no wrapping of the protective tape 14. In addition, since there is no portion of the protective tape 14 that protrudes or separates from the outer peripheral edge of the wafer 12, polishing debris do not accumulate on the back side of the protective tape 14 and do not accidentally peel off.
[0018]
Next, a second embodiment of the protective tape attaching device of the present invention will be described with reference to FIG. Here, the same members as those in the above embodiment are denoted by the same reference numerals, and description thereof will be omitted. In this embodiment, the concave portion 16 of the base 18 is formed deeper than the thickness of the wafer 12, and the protective tape 14 is formed on the outer peripheral edge of the wafer 12 by the stepped portion formed by the concave portion 16 of the base 18 as a jig. This forms a space 14a. By adjusting the cutting edge of the cutter 58 so as to be positioned in the space 14a and rotating the cutter 58, the same effect as in the above embodiment can be obtained. In this case, since the space 14a is formed by using the concave portion 16 of the base 18, the number of components is small, the positioning of the mask member 22 does not need to be performed, and the operation is quick.
[0019]
Next, a third embodiment of the protective tape attaching device of the present invention will be described with reference to FIG. Here, the same members as those in the above embodiment are denoted by the same reference numerals, and description thereof will be omitted. In this embodiment, the base 18 as a jig is provided with an opening 62 in which the wafer 12 is fitted and an opening 62 slightly smaller than the wafer 12 concentrically. , 62, the wafer transfer member 64 holding the back surface of the wafer 12 by suction is lifted, and the wafer 12 is positioned on the base 18. At this time, the position of the surface 12a of the wafer 12 is located immediately below the opening 62 in the opening 61 of the base 18, and the opening 62 is located slightly inside the outer peripheral edge of the wafer 12. Then, similarly to the above embodiment, the protection tape 14 is cut off slightly inside the outer peripheral edge of the wafer 12 by the cutter 58.
[0020]
According to this embodiment, the wafer 12 can be loaded from below the base 18, and the protection tape can be stuck in a series of steps by sequentially transporting the wafers 12.
[0021]
Next, a fourth embodiment of the protective tape attaching device according to the present invention will be described with reference to FIG. Here, the same members as those in the above embodiment are denoted by the same reference numerals, and description thereof will be omitted. In this embodiment, the wafer transfer member 64 has a base 18 which is a jig having an opening 66 substantially equal to the wafer 12, and holds the back surface of the wafer 12 by suction from below the opening 66 of the base 18. And the wafer surface 12a is positioned slightly below the surface of the base 18. Thereafter, the protective tape 14 is cut off slightly inside the outer peripheral edge of the wafer 12 by the cutter 58 as in the above embodiment.
[0022]
In this embodiment as well, the wafer 12 can be carried in from below the base 18, the wafer 12 can be sequentially transferred, and the protection tape can be stuck in a series of steps, and the configuration of the base 18 is also simple. Things.
[0023]
Incidentally, the protective tape positioning means, the pressing roller, the cutter moving device, the cutter blade and its driving device of the present invention can be appropriately selected, and the structure of the jig for forming a step with the wafer surface is also suitable. It can be selected as appropriate.
[0024]
【The invention's effect】
ADVANTAGE OF THE INVENTION The protective tape sticking method and sticking apparatus of this invention can stick a protective tape reliably in the range inside a wafer surface with a simple structure, and a protective tape will get in the way in a back grinding process and an etching process later. This greatly contributes to the thinning of the wafer.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view schematically showing a protective tape attaching device according to a first embodiment of the present invention.
FIG. 2 is a longitudinal sectional view schematically showing a cutter device of the protective tape attaching device according to the embodiment.
FIG. 3 is a front view schematically showing an urging device of the protective tape attaching device according to the embodiment.
FIG. 4 is a plan view of a wafer to which a protective tape has been attached by the protective tape attaching apparatus of this embodiment.
FIG. 5 is a longitudinal sectional view of a wafer to which a protective tape has been attached by the protective tape attaching apparatus of the embodiment.
FIG. 6 is a longitudinal sectional view schematically showing a protective tape attaching device according to a second embodiment of the present invention.
FIG. 7 is a longitudinal sectional view schematically showing a protective tape attaching device according to a third embodiment of the present invention.
FIG. 8 is a longitudinal sectional view schematically showing a protective tape attaching device according to a fourth embodiment of the present invention.
FIG. 9 is a longitudinal sectional view of a wafer to which a protective tape has been attached by a conventional protective tape attaching apparatus.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Protective tape sticking device 12 Wafer 14 Protective tape 16 Concave part 18 Base 20 Opening 22 Mask member 24 Press roller 30 Urging device 50 Cutter device 58 Cutter

Claims (8)

A jig having a step located outside the outer peripheral edge of the surface of the semiconductor wafer and substantially slightly above the outer surface of the wafer along the outer peripheral edge is provided. Affix the protective tape to the jig so as to cover the step of the jig, cover the entire surface of the wafer with the protective tape, and attach the protective tape stuck to the wafer surface and the step of the jig. Cutting the wafer along the step at a position slightly inside the outer peripheral edge of the wafer. 2. The method according to claim 1, wherein the protective tape, which is attached to the surface of the wafer and cut off inside the outer peripheral edge of the wafer, is pressed against the surface of the wafer by a soft pressing roller to make close contact. . After attaching the protection tape to the jig, a cut is made at a position along the wafer flat portion, and then the protection is performed by a cutter whose blade rotates at a position slightly inside the outer peripheral edge of the wafer. 2. The method according to claim 1, wherein the tape is cut off. A jig having a step located outside the outer peripheral edge of the surface of the semiconductor wafer and substantially slightly above the outer surface of the wafer along the outer peripheral edge thereof, and a protective tape covering the entire surface of the wafer. Protective tape positioning means for positioning the jig on the step portion and the wafer surface; a cutter having a cutting edge positioned between the wafer surface and the jig step portion; and A drive device for rotating along the outer peripheral edge slightly inside the outer peripheral edge. 5. The protective tape applying apparatus according to claim 4, further comprising a soft pressing roller for pressing the protective tape attached to the wafer surface against the wafer surface to bring the protective tape into close contact therewith. 5. The apparatus according to claim 4, wherein the jig is a mask member having an opening surrounding an outer peripheral portion of the wafer. 5. The protective tape sticking apparatus according to claim 4, wherein the jig is a base on which a concave portion for positioning the wafer is formed. 5. The apparatus according to claim 4, wherein the jig is a base on which an opening for positioning the wafer is formed.

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