JPH0536657A - Protective tape cutting device for semiconductor wafer - Google Patents

Abstract

PURPOSE:To prevent the periphery of an orientation flat from being damaged by a cutting blade piece when a protective tape attached to a semiconductor wafer is cut along the periphery of the orientation flat with the cutting blade piece. CONSTITUTION:The contact angle of a cutting blade piece 21 against the periphery of an orientation flat OF is prevented from becoming larger by constituting a cutter holder equipped with the cutting blade piece 21 so that the holder can swing around the vertical axis of the holder and guiding a roller 23 interlocked with the cutting blade piece 21 by means of a guiding member 27 on the orientation flat OF.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for cutting out a protective tape attached to the surface of a semiconductor wafer which has been subjected to a pattern forming process, along the outer peripheral shape of the wafer.

[0002]

2. Description of the Related Art When a back surface of a semiconductor wafer on which a pattern has been formed is polished (back-ground), a protective tape having weak adhesiveness is attached to the front surface of the wafer in advance, and the wafer surface protected by the protective tape is sucked. Absorb and hold at to perform polishing treatment.

When this protective tape is attached to the surface of a semiconductor wafer, a protective tape wider than the diameter of the wafer is attached to the entire surface of the wafer, and then the protective tape is attached to the outer peripheral edge of the wafer so that there is no protrusion. It is required to cut along.

Conventionally, in order to perform such processing, as shown in FIG. 5, a cutting blade piece which is rotatable around the center of the wafer is arranged above the semiconductor wafer W to which the protective tape T is attached.
By rotating this cutting blade piece once, a means for cutting out the protective tape along the outer peripheral edge of the wafer is taken.

FIG. 6 is a plan view showing the outline of a conventional device for performing the above-mentioned cutout. Vertical axis X approximately the same as the center of the wafer W
The cutter unit 2 which is rotated around is slidable in the radial direction of rotation of the cutter unit 2 and has a vertical axis X.
The cutter holder 3 which is biased by the spring 17 toward the side is supported, and the cutting blade piece 21 is attached to the cutter holder 3 at a constant inclination angle θ with respect to the radial direction. The constant inclination angle θ around the periphery
The protective tape T was cut out by moving it in the circumferential direction while making contact with the contact angle.

[0006]

However, the above-mentioned conventional device has the following problems. In the above conventional apparatus, a constant contact angle θ is always maintained in the region where the cutting blade piece 21 acts on the arc edge of the wafer W.
In the region where the cutting blade piece 21 acts on the orientation flat OF, as shown in FIG. 6, the contact angle of the cutting blade piece 21 with respect to the straight peripheral edge of the orientation flat OF gradually increases as the cutting blade piece 21 advances.

Therefore, in the latter half of the orientation flat, the equivalent contact angle of the cutting blade 21 with the wafer edge increases, so that stress concentrates on that portion and the wafer edge is easily damaged. there were. In particular, in a brittle wafer such as a thin wafer W or a gallium arsenide wafer, the probability of occurrence of defects is high.

The present invention has been made in view of the above circumstances, and provides a protective tape cutting device for a semiconductor wafer, which can cut smoothly and satisfactorily without causing a wafer defect in an orientation flat. The purpose is to do.

[0009]

In order to achieve the above object, the present invention has the following constitution. That is, the present invention is a device for cutting out a protective tape attached to the surface of a semiconductor wafer along the outer peripheral shape of the wafer, and a wafer support table for mounting and holding the semiconductor wafer in a fixed posture, and the wafer support table. On the table, a cutter unit for cutting that is rotated around a vertical axis that is substantially concentric with the table, and a cutter unit that is slidable in the radial direction of rotation of the cutter unit and is biased toward the vertical axis side. The cutter holder assembled to the cutter unit and the cutter holder are configured to be rotatable and swingable around the vertical axis, and the cutting blade provided on the cutter holder has a constant angle with the outer circumferential surface of the arc of the wafer in plan view. Urging means for oscillating and urging the cutter holder so that the cutter holder comes into a fixed posture and the cutting edge piece reaches one end of the orientation flat of the wafer. A guide means for reducing the contact angle of the cutting edge pieces cutter holder from the point is retracted swung against the swing biasing force of the biasing means against the edge of the orientation flat was, but with the.

[0010]

According to the present invention, a constant contact angle is supported in the area where the cutting blade acts on the outer peripheral edge of the arc of the wafer as in the conventional apparatus, but when it enters the area of the orientation flat, the guide means acts. When the cutter holder is swung backwards, the cutting blade moves with a small contact angle to the edge of the orientation flat, and when it passes the orientation flat, the cutter holder released from the guide means swings back to its original posture and swings. The blade piece acts on the peripheral edge of the wafer arc with a constant contact angle to continue cutting.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a vertical sectional view of an embodiment of a protective tape cutting device according to the present invention.

This device is basically similar to the conventional example,
A wafer support table 1 on which a semiconductor wafer W is mounted and suction-held, a cutter unit 2 for cutting out a protective tape which is rotated about a vertical axis X substantially concentric with the wafer support table 1, and this cutter unit 2. And a cutter holder 3 assembled to the cutter unit 2 by being slidable in the rotation radius direction and being biased toward the vertical axis X side.

An annular groove 4 for passing a cutter is concentrically formed on the upper surface of the wafer support table 1, and a suction groove 5 is formed at the center of these grooves.

The cutter unit 2 for cutting is connected to a lower end of a rotary shaft 9 which is rotatably supported around a vertical axis X through a support plate 7 and a bearing bracket 8 in a case 6 which can be opened and closed vertically. By operating a handle (not shown) attached to the upper end of the rotating shaft 9 protruding from the upper surface of the case 6, the cover case 6 is rotated from the outside.

A square block 10 is connected to a lower portion of the rotary shaft 9, and a pair of left and right slide shafts 11 are horizontally penetrated through the square block 10 so as to sandwich a vertical axis X. The front and rear ends of both slide shafts 11 are connected and integrated by shaft pressing members 12 and 13. The cutter holder 3 is mounted on a support block 14 connected and fixed across both slide shafts 11 so as to be swingable around a vertical axis P.

Further, the spring bearing 15 provided in the square block 10 and the spring bearing 1 mounted in the middle of the slide shaft 11
6, a tension spring 17 is stretched and the slide shaft 11 and the cutter holder 3 are entirely biased rearward, that is, toward the vertical axis X, which is the center of rotation.

Next, the cutter holder 3 and its supporting structure will be described in detail with reference to FIGS. 2 and 3. 2 is a plan view of the cutter holder mounting portion, and FIG. 3 is a front view thereof.

At the center of the support block 14 connected to the slide shaft 11, a support shaft 18 is rotatably supported around a vertical axis P, and at the lower end of the support shaft 18, the cutter holder 3 is raised by a bolt 19 to a height. Adjustably installed.
The cutting blade piece 21 held by the support piece 20 on the front side of the cutter holder 3 has a lower end acting portion at the vertical axis P.
It is located on the upper side and is attached so as to be slightly tilted forward with respect to the cutter moving direction, and its front tilt angle, that is, the cutting angle can be adjusted through the long hole 22 centered on the lower end working portion. ing.

At the upper end of the support shaft 18, the roller 2 is provided at the free end.
The operation arm 24 provided with 3 is connected and fixed, and
A spring 25 is stretched between the operation arm 24 and the support block 14, and the operation arm 24 is urged to swing clockwise in FIG. The oscillatingly biased operation arm 24 is supported by abutting against a stopper 26 provided on the support block 14 side, and is received and held in a fixed posture. Then, in this receiving state, the stopper 26 is adjusted so that the cutting blade piece 21 has a predetermined inclination angle θ with respect to the cutter moving direction in plan view.

The roller 23 is the case 6 shown in FIG.
It is provided at a height at which it comes into contact with a guide member 27 made of a straight plate material provided on the lower surface of the support plate 7, and is used for controlling the attitude of the cutter holder 3 as described later.

Reference numeral 28 in FIG. 3 is a tape retainer supported by a support plate 29 attached to the cutter holder 3 via a pair of left and right support shafts 30 so as to be vertically movable.
In the normal state, the spring 31 displaces downward to protect the cutting blade 21, and when it is placed on the upper surface of the wafer W, it is elastically retracted relatively upward so that the cutting blade 21 comes out of the central opening 32.
The lower end working part of is exposed.

Further, as shown in FIG. 1, a heater 33 for appropriately heating the cutting blade 21 and a thermocouple 34 as a temperature control sensor are embedded in the holder body 3. The heater 33 and the thermocouple 34 are wire-connected to a slip ring 36 concentrically mounted on a Bakelite rotary drum 35 connected to the rotary shaft 9. Sliding contact terminals 37, which slidably contact the slip rings 36, are mounted on the support plate 7 via wiring holders 38, thereby providing a temperature controller (not shown) and a rotary system. The heater 33 and the thermocouple 34 are electrically connected.

Next, the cutting process of the protective tape using this device will be described. (1) At the time of processing, first, the cover case 6 is opened upward, the semiconductor wafer W is manually aligned and placed on the wafer support table 1 concentrically, and the semiconductor wafer W is suction-held. At this time, the cutting cutter unit 2 provided on the cover case 6 side is exposed to the front surface, but the tape holder 28 in the free state erroneously touches the working portion of the cutting blade piece 21 to conceal the cutting blade piece 21 from the outside. There is no fear. (2) Attach the protective tape T to the wafer surface. (3) Next, lower the cover case 6 to remove the cutter unit 2.
Is set at a specific position on the outer peripheral portion of the semiconductor wafer W, and the working portion of the cutting blade piece 21 is brought into contact with the protective tape T. On this occasion,
First, the tape retainer 28 comes into contact with the protective tape T, and the tape retainer 28 is pushed up by the reaction force thereof, and the working portion of the cutting blade piece 21 pierces the protective tape T. (4) Next, the rotary shaft 9 is rotated on the cover case 6 so that the cutter unit 2 makes one round around the semiconductor wafer W, so that the protective tape T is cut out along the outer circumference of the wafer.

In this case, as shown in FIG. 4, while the cutting blade piece 21 travels along the arc outer peripheral edge of the wafer W, the cutting blade piece 2
1 contacts the outer peripheral edge of the wafer at a predetermined contact angle θ. Then, when the cutting blade piece 21 reaches the front end of the orientation flat OF, the cutting blade piece 21 becomes substantially parallel to the peripheral edge of the orientation flat OF. Moreover, here, the roller 23 of the operation arm 24 is fixed to the guide member 2
The inner surface of 7 starts contacting.

As the cutter unit 2 further rotates, the operation arm 24 is guided by the guide member 27.
Is reciprocally rocked against the spring 25, and the cutter holder 3 rocks integrally with the spring 25 so that the cutting edge piece 21 has a posture substantially along the peripheral edge of the orientation flat OF.
That is, the tape is cut out along the orientation flat OF while moving forward with almost no contact angle.

Then, when the cutting edge piece 21 reaches the end of the orientation flat OF, the guide member 27 is formed.
On the other hand, the roller 23 becomes free, the operating arm 24 is returned to the original posture by the spring 25, and the cutting blade piece 21 moves along the arc outer peripheral edge of the wafer W again with the original contact angle θ.

The outer guide member 27 is used for the wafer Wa having a large diameter. Further, as the guide member, besides the plate material as described above, a guide groove can be used. Further, the cutter unit may be of a type that is not only manually operated but also automatically driven.

[0028]

As is apparent from the above description, according to the present invention, when the protective tape is cut out along the arcuate outer periphery of the wafer, the cutting blade has a constant contact angle with the outer peripheral edge of the wafer. When the cutting edge piece reaches the end of the orientation flat by operating the blade, the contact angle of the cutting edge piece is reduced by the action of the guide means, so the contact angle of the cutting edge piece in the orientation flat increases. It is possible to smoothly cut out the protective tape while avoiding chipping.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional side view of an embodiment of a semiconductor wafer protective tape cutting device according to the present invention.

FIG. 2 is a plan view of a cutter holder mounting portion.

FIG. 3 is a partially cutaway front view of a cutter holder portion.

FIG. 4 is a plan view showing a tape cutting operation.

FIG. 5 is a perspective view showing a protective tape cutting processing mode.

FIG. 6 is a plan view showing a tape cutting operation by conventional means.

[Explanation of symbols]

 1 ... Wafer support table 2 ... Cutter unit 3 ... Cutter holder 21 ... Cutting blade piece 23 ... Roller 24 ... Operation arm 25 ... Spring 27 ... Guide member X ... Vertical axis W ... Semiconductor wafer OF ... Orientation flat

Claims (1)

Claim: What is claimed is: 1. A wafer support table for cutting out a protective tape attached to the surface of a semiconductor wafer along the outer peripheral shape of the wafer, the wafer supporting table holding and holding the semiconductor wafer in a fixed posture. A cutter unit for cutting that is rotated on the wafer support table about a vertical axis substantially concentric with the wafer support table; and a cutter unit that is slidable in a rotation radius direction of the cutter unit.
Further, a cutter holder that is biased toward the vertical axis side and is assembled to the cutter unit, and the cutter holder is configured to be rotatable and swingable around the vertical axis, and the cutting blade provided on the cutter holder is a flat surface. Urging means for oscillating and urging the cutter holder in a state in which the cutter holder is in contact with the outer peripheral surface of the wafer at a constant angle, and from the time when the cutting edge piece reaches one end of the orientation flat of the wafer. Guide means for reducing the contact angle of the cutting edge piece with respect to the edge of the orientation flat by swinging the cutter holder backward against the swing biasing force of the biasing means. Protective tape cutting device.