JPH084979B2 - Work table for dicer - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a work table in a dicer equipped with a cleaning device for cleaning a semiconductor wafer that has been cut. More specifically, the present invention relates to a work table for a dicer that has the functions of both a spinner table that rotates at high speed and a chuck table that accurately performs rotation indexing.

(Background of the Invention) In the dicing processing technology for semiconductor wafers (hereinafter referred to as "wafers"), a cut wafer is braked and shredded into chips, but chips and the like adhering to the wafer are removed before breaking. Therefore, a dicer capable of continuously performing automatically from cutting to cleaning treatment has been developed and put into practical use.

However, the dicer has a problem that the wafer handling structure is complicated and causes troubles, and it is difficult to sufficiently perform the cleaning process.

That is, the dicer is, for example, an alignment device that aligns the streets of the wafer with the reference cutting line of the cutter (hereinafter referred to as alignment), a cutting device that cuts the aligned wafers along the streets, and a cut wafer. Although it is equipped with a cleaning device that sprays high-pressure water etc. to remove chips, etc., the handling of the wafer is different at the time of alignment and cutting, and at the time of cleaning processing, and the wafer during alignment and cutting is handled differently. It is necessary that the streets be precisely rotationally indexed so as to be positioned in parallel with the cutter, and that the cut wafers be rotated at high speed during the cleaning process. Therefore, two kinds of work tables having different functions, that is, a chuck table for precisely rotating and indexing and a spinner table for rotating at high speed are provided. Also,
In order to perform a cleaning process after cutting, it is necessary to transfer the cut wafer from the chuck table to the spinner table, and a transfer belt, a transfer device such as a robot is provided between them.

As described above, in order to perform the cutting and the cleaning process continuously, it is necessary to provide two types of work tables having different functions and a transfer device for connecting the two, which makes the wafer handling structure complicated. Has become.

In the cleaning process, the cut wafer is placed on the spinner table by the transfer device, high-pressure water is sprayed while the spinner table is rotating at a relatively low speed to clean the wafer, and then the spinner table is cleaned. Is performed by rotating the wafer at a relatively high speed to dry the wafer, but during the transfer from the chuck table to the spinner table, the cut wafer may dry and chips etc. may adhere firmly to the wafer. There is a problem that it is difficult to do.

(Object of the Invention) The present invention has been made to solve the above-mentioned conventional problems, and an object thereof is to combine the functions of both a spinner table and a chuck table, and can be used for alignment, cutting and cleaning processes. To provide a work table.

(Structure of the Invention) The present invention has a function as a spinner table by directly connecting a first drive motor, such as an AC servo motor or the like, that rotates at a high speed, to a rotation shaft of a turntable that suction-holds a wafer through a coupling or the like. A friction motor drive member such as a friction drive wheel, a belt, and a wire is brought into pressure contact with the rotary disk, and the friction drive transmission member is rotated by a minute angle. By connecting to the second drive motor to have a function as a chuck table, a work table having both functions of a spinner table and a chuck table is configured.

That is, the structural feature of the present invention is that the rotary disk for sucking and holding the wafer, the first drive motor for rotating the rotary disk at a high speed, and the rotary disk for rotating a minute angle via the friction drive transmission member, The second drive motor is provided so that the drive transmission to and from the turntable can be connected and disconnected.

(Example) An example of the present invention will be described with reference to the drawings. This embodiment is applied to the dicer shown in FIG. 4, and in FIG. 4, 1 is a cutting device provided with a cutter 2 which is positionally adjustable at predetermined intervals in the axial direction, and 3 is patterned. A detection device 4 for detecting the streets of the wafer W by a microscope or the like, and a calculation and display device 5 for calculating and displaying the alignment state between the reference cutting line and the streets based on a signal from the detection device 4. The alignment device 6 includes a jet nozzle for jetting high-pressure water or the like,
A cleaning device for removing chips and the like from the cut wafer W, and a work table device 7 for adsorbing and holding the wafer W.

The work table device 7 is slidably provided on the support rail 12 so that the first moving table 8 is reciprocally moved in the direction of arrow A by the first moving device 11, and the second moving table 9 is the second moving device. A work table 10 is provided on the second moving table 9 slidably provided on the first moving table 8 so as to be moved in the direction of the arrow B by 13.

The work table 10 is configured as shown in FIGS. 1 to 3, and a vacuum groove 22 is formed on the upper surface of the rotary table 20, and a suction plate 21 is fixed so as to cover the vacuum groove 22. The suction plate 21 is a porous material such as porous ceramics,
It is composed of a perforated plate having a large number of small holes, etc., and is connected to a vacuum source (not shown) via a switching valve to supply suction air via a vacuum line described later to suck and hold the wafer W. is there.

A support base 23 is integrally provided on the lower surface of the turntable 20. The support base 23 is rotatably supported by a first bearing 31 and a second bearing 32 on a base 30 fixed to the second moving base 9. ing. A rotary shaft 24 is provided at the center of the support base 23,
An AC servomotor 26 for high speed rotation is connected to one end of the rotary shaft 24 via a coupling 25. The AC servomotor 26 is controlled so as to rotate at a relatively low speed when cleaning with high-pressure water or the like and to rotate at a relatively high speed when drying after cleaning. A seal member 28 connected to a vacuum tube 29 is slidably provided on the outer peripheral surface of the rotary shaft 24, one end of which communicates with the vacuum groove 22 and the other end of which communicates with the seal member 28 and which is connected to the rotary shaft 24. Vacuum holes 27 are formed at a plurality of locations on the outer peripheral surface so as to open. The vacuum tube 29 is connected to a vacuum source via a switching valve (not shown), and the vacuum groove 22, the vacuum hole 27, and the seal member 28 form a vacuum line.

A ring-shaped friction wheel 33 made of rubber, plastic or the like having a plurality of ring-shaped grooves 34 formed on the outer peripheral surface of the rotary disc 20.
Is fixed to the friction wheel 33, and a friction drive wheel 35 in which a groove 36 that engages with the ring-shaped groove 34 is formed is provided so as to be capable of pressure contact and separation. That is, the friction drive wheel 35 is connected to a pulse motor 37 that is rotationally driven to a small angle, and the pulse motor 37 is swingably supported at one end of a support bracket 38 whose both lower side surfaces are fixed to the base 30. ing. Further, a rod 40 of a solenoid 39 fixed to the base 30 is connected to one end of a lower portion of the pulse motor 37,
A spring 41 is provided between the upper end of 37 and the base 30 so as to draw the pulse motor 37 toward the rotary table 20. When the solenoid 39 is turned on, the rod 40 retracts,
When off, the rod 40 is actuated to project. Therefore, in the pulse motor 37, the friction drive wheel 35 resists the elastic force of the spring 41 when the solenoid 39 is turned on.
When the solenoid 39 is turned off, the friction drive wheel 35 is moved in the direction of pressing the friction wheel 33 by the elastic force of the spring 41. It is preferable that the friction drive wheel 35 is strongly pressed so as not to slip with the friction wheel 33 when being pressed against the friction wheel 33.

A ring-shaped rotation angle reading scale 42 is fixed to the outer peripheral surface of the turntable 20 adjacent to the friction wheel 33, and a reading head 43 is provided on the base 30 so as to face the rotation angle reading scale 42. . The rotation angle reading scale 42 and the reading head 43 are rotation angle detectors that detect the rotation angle of the turntable 20. The movement amount of the rotation angle reading scale 42 is detected by the reading head 43, and a signal from the reading head 43 The drive amount of the pulse motor is controlled so that the rotation angle of the turntable 20 can be set precisely.

The present embodiment is configured as described above and operates as follows.

In the dicer shown in FIG. 4, the patterned wafer W is subjected to alignment, cutting and cleaning processes while the work table device 7 reciprocates between a position corresponding to the alignment device 3 and a position corresponding to the cleaning device 6. Are sequentially performed.

That is, the patterned wafer W is rotated by the carry-in device (not shown) or the turntable 20 of the work table device 7 when the work table device 7 is positioned at a position corresponding to the detection device 4 of the alignment device 3.
The vacuum line is placed on top of the vacuum line, and the vacuum line is connected to the vacuum source to be sucked and held by the suction plate. After that, for example, the streets in two directions formed on the wafer W are sequentially aligned by the alignment device 3. First, on one of the streets, after rotating and indexing the turntable 20 so that the direction becomes parallel to the reference cutting line, by adjusting the position of the second movable table 9 in the direction of the arrow B so as to match the reference cutting line. Align. Then turntable 20
After 90 ° rotation indexing and adjusting the direction of the other street in the same manner as described above, the position is adjusted in the direction of arrow B.

After the alignment is completed, the work table device 7 is moved to a position before the position corresponding to the cutter 2 of the cutting device 1 and stopped. Then, after the cutter 2 is lowered to the set processing position, the work table device 7 is moved to start cutting on one of the streets.
For one of the streets, the cutter 2 is lifted after the cutting of the first street is completed, and the work table device 7 is returned to the stop position. Next, the position of the cutter 2 is adjusted in the axial direction, the cutter 2 is lowered to the processing position, the work table device 7 is moved again, and the next street is cut. Thereafter, similarly, all the streets of one street are sequentially cut.

After cutting all streets for one street, turntable 20 of work table device 7
Is rotated by 90 ° and the other street is set so as to correspond to the cutter 2, and thereafter, cutting is sequentially performed as in the case of one street.

When the cutting of the other street is completed, the work table device 7 is moved to a position corresponding to the cleaning device 6, the turntable 20 is rotated at a relatively low speed, and high-pressure water or the like is sprayed from the cleaning device 6, Cutting chips and the like are removed from the cut wafer W. Then, after that, the injection of high-pressure water or the like is stopped and the turntable 20 is rotated at a relatively high speed to dry the wafer.

After the cleaning process is completed and the rotation of the turntable 20 is stopped,
The cut-out wafer W is unloaded by an unillustrated unloading device or manual work. Then, the work table device 7 is returned to the position corresponding to the alignment device 3,
A new wafer W is placed in the same manner as described above, and thereafter, alignment, cutting and cleaning processes are repeated in the same manner.

In the above wafer W processing step, the turntable 20 of the work table device 7 is rotationally indexed during alignment and cutting, and is rotated at a relatively low speed and then at a relatively high speed during the cleaning process. Is done as follows.

During alignment and cutting, the AC servo motor 26 is set to the non-energized state, and the pulse motor 37 is set to the energized state. Further, since the solenoid 39 is set to the non-operating state, the pulse motor 37 is tilted toward the turntable 20 by the spring 41 so that the friction drive wheel 35 presses the friction wheel 33. In this state, for example, when aligning one street of the wafer W, the pulse motor 37 is driven by a signal from the alignment device 3, and the pulse motor 37 is driven by the friction drive wheel.
It is transmitted to the friction wheel 33, that is, the turntable 20 via 35, and is rotationally indexed so that the street becomes parallel to the reference cutting line. Further, after the streets are aligned, the pulse motor 37 is driven so that the rotary disc 20 is indexed by 90 °. The drive amount of the pulse motor 37 is a rotation angle reading scale 42 that rotates together with the rotary disc 20. Is performed by detecting the amount of movement of the reading head 43. Since the AC servo motor 26 is in the non-energized state, the rotary disc 20 is smoothly rotated by the friction drive wheel 35, and the friction drive wheel 35 is strongly pressed against the friction ring 33 of the rotary disc 20 by the spring 41. As a result, the rotation is transmitted from the friction drive wheel 33 to the friction wheel 35 without causing slippage, and the rotation angle detector detects the actually indexed angle of the turntable 20. The rotation is indexed.

During the cleaning process, the solenoid 39 is operated and the pulse motor 37 is tilted so that the friction drive wheel 35 is separated from the friction wheel 33. Then, the AC servomotor 26 is driven, and the turntable 20 is rotated at a relatively low speed and then at a relatively high speed.

As described above, the present embodiment can smoothly and precisely perform the rotation indexing and the high-speed rotation of the turntable 20. In particular, the rotation indexing is performed by the friction drive wheel 35, so that the rotation indexing can be performed with precision, and even when an external force acts on the spinning plate 20 during cutting, etc.
20 is fixed by the friction drive wheel 35 and can maintain the indexing angle accurately without moving.

The present invention is not limited to this example,
For example, the pulse motor 37 and the turntable 20 may be configured to be capable of friction drive transmission by a belt, a wire, or the like. Also, attach a pinion gear to the pulse motor 37,
The gear may be attached to the turntable 20 to transmit the drive.

(Effects of the Invention) As described in the embodiments, the present invention makes it possible to accurately perform rotation indexing by the fact that the turntable is connected to the second drive motor that rotates to a minute angle via friction drive wheels. In addition, the movement of the rotary disc after rotation indexing can be prevented and the indexing angle can be maintained accurately, and the first drive motor that rotates at high speed is connected to the rotary disc.
It is possible to combine the functions of both a chuck table and a spinner table, and it is possible to construct a dicer equipped with a cleaning device with a simple structure without complicating the wafer handling structure as in the past. is there.

[Brief description of drawings]

FIG. 1 is a front view of an embodiment of the present invention, a part of which is shown by a broken surface. FIG. 2 is a plan view showing a part of the same in a broken plane, FIG. 3 is an enlarged cross-sectional view taken along the line III-III of FIG. 2, and FIG. It is a perspective view shown. 1 ... Cutting device, 3 ... Alignment device, 6 ... Cleaning device, 7 ... Work table device, 10 ... Work table, 20 ... Rotating plate, 21 ... Suction plate, 26 ... AC servo motor, 33 …… friction wheel, 35 …… friction drive wheel, 37 …… pulse motor, 39 …… solenoid, 41 …… spring, 42 …… rotation angle reading scale, 43 …… reading head, W ……
Wafer.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display location H01L 21/301

Claims (2)

[Claims] 1. In a dicer equipped with a cleaning device, a rotary disk that holds a wafer by suction, a first drive motor that rotates the rotary disk at a high speed, and a rotary disk that rotates a rotary disk to a small angle via a friction drive transmission member. At the same time, the drive transmission with the turntable is connected.
A work table for a dicer, comprising a second drive motor provided so as to be separable. 2. A friction wheel is provided on the outer peripheral surface of the rotary disk,
The friction drive transmission member is a friction drive wheel, and the second drive motor is swingably provided so that the friction drive wheel can be pressed against and separated from the friction wheel.
Work table for dicer according to item.