JP3117891B2 - Wafer cleaning slice base peeling equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for manufacturing a wafer of silicon or the like which is used as a material of a semiconductor device, and more particularly to an apparatus for cutting an ingot by a slicing machine, a wire saw or the like (hereinafter simply referred to as "cutting machine"). The present invention relates to an apparatus having a function of cleaning a cut wafer, peeling a slice base adhered to a substrate portion of the wafer, and storing the wafer having the slice base peeled in a cassette.

[0002]

2. Description of the Related Art A wafer made of silicon or the like as a material of a semiconductor element is manufactured by being cut by a cutting machine from an ingot state, and a slice base is adhered to the ingot so that a cut end portion is not chipped at the time of cutting. , Including the slice base. Accordingly, the wafer 10 after cutting has the shape shown in FIG. 9, and the slice base 10b is peeled off from the base portion 10a such as silicon after cutting.

[0003] As a peeling method, the adhesive bonding the slice base 10b to the base portion 10a is softened, and in this state, the slice base 10b is pressed in the thickness direction of the wafer 10 and peeled. As a method, a method of heating the wafer 10 in hot water, a method of heating the base portion 10a with a clamp table having a built-in heater, a method of directly heating the bonded portion with hot air, and a method of using a slice base receiving plate having a built-in heater There is a method of heating the slice base 10b.

Further, the cut wafer 10 needs to be cleaned before and after the peeling of the slice base 10b to remove cutting chips and cutting fluid attached at the time of cutting, and furthermore, the peeling and cleaning are completed. It is necessary to store the base material portion 10a of the wafer 10 in a cassette for the next manufacturing process.

[0005]

Conventionally, however, the separation, cleaning, and storage are often performed in separate apparatuses. In this case, not only the equipment cost of the entire wafer manufacturing apparatus is increased, but also the installation of the apparatus is not required. The area increases,
Furthermore, there is a problem that it takes time since an operator often manually carries in and out between these processes.

Further, in the method of softening the adhesive by putting the wafer 10 in hot water for peeling, maintenance of the hot water is troublesome, the installation area of the apparatus tends to be large, and Since the temperature is about 100 ° C., it is necessary to take sufficient safety measures.

Further, the attitude of the wafer 10 is often handled with the thickness direction being a vertical direction (hereinafter referred to as "lateral attitude"). In this attitude, the installation area of the apparatus generally increases, and The wafer 10 is easily bent,
If this state is maintained for a long time, the flatness of the wafer 10 may be deteriorated. In particular, in recent years, the diameter of the wafer 10 has been increasingly increased due to improvement in semiconductor production efficiency and the like, and this influence cannot be ignored. Also, if the cleaning liquid is kept in this position after cleaning, the cleaning liquid remains and the wafer 1
The surface of 0 is easily stained.

The present invention has been made in view of such circumstances, and automatically performs cleaning, peeling, and storing in a short time, has a small installation area, is inexpensive, and has a low cost.
It is an object of the present invention to provide a wafer-cleaning slice-based peeling apparatus which is less likely to deteriorate the flatness of the wafer or cause spots.

[0009]

According to the present invention, in order to achieve the above object, a wafer cleaning slice-based peeling apparatus is provided with cleaning, peeling, and storing functions in a single apparatus, so that a wafer cleaning slice is removed. The wafer 10 is pressed against a clamp table having a built-in heater by pressing the wafer 10 on a clamp table having a built-in heater.
And the wafer 10 is handled with the attitude of the wafer 10 mainly set in the horizontal direction in the thickness direction of the wafer 10 (hereinafter referred to as “vertical attitude”).

That is, the wafer cleaning slice-based peeling apparatus is configured as follows. (A) A cleaning unit is provided to clean the wafer 10 cut from the ingot. (B) A drying / peeling section is provided, while blowing dry air onto the washed wafer 10, fixing the wafer 10 to a clamp table heated to a predetermined temperature, and slicing the wafer 10 to the base portion 10a of the wafer 10. The base 10b is peeled off. (C) A storage section is provided, and a cassette for storing the wafer 10 from which the slice base 10b has been peeled off is provided. (D) A first transfer unit is provided to receive the wafer 10 unloaded from the cutting machine in the horizontal position, load the wafer 10 into the cleaning unit, and unload it from the cleaning unit. (E) A second transfer unit is provided, receives the wafer 10 unloaded from the cleaning unit from the first transfer unit, rotates the wafer 10 from the horizontal position to the vertical position, and then loads the wafer 10 into the drying / separation unit. Further, the wafer 10 from which the slice base 10b has been peeled is stored in the cassette of the storage unit.

In this case, the first transfer section can be provided with a function of tilting the wafer 10 when the wafer 10 is unloaded from the cleaning section. Further, the horizontal feed of the second transport unit is driven by a screw by a servo motor or the like. Further, the wafer holding means of the second transfer section may have a function of rotating the wafer 10 by 90 ° in the circumferential direction.

[0012]

The wafer 10 cut from the ingot by the cutting machine is carried out in a horizontal posture, carried into the cleaning unit by the first transfer unit, and washed. Cleaned wafer 10
Is transported out of the cleaning unit by the first transport unit, transferred to the wafer holding unit of the second transport unit, and then rotated to a vertical posture. Next, in that posture, the wafer 10 is carried into the drying / peeling unit by the second transfer unit, and is blown with dry air, and is fixed to a clamp table heated to a predetermined temperature to soften the adhesive. Then, the slice base 10b is peeled off. Further, the wafer 10 from which the slice base 10b has been peeled is transported to the storage unit by the second transport unit and stored in the cassette.

In this case, after the wafer 10 is cleaned, the wafer 10 is placed in a vertical position, so that water droplets and the like are easily removed by the cleaning, and there is little possibility that stains remain. In particular, the wafer 10
When the wafer 10 is carried out of the cleaning unit, the water drain is improved by tilting the wafer 10.

If the horizontal feed of the second transfer unit is driven by a screw by a servomotor, the pitch at which the wafers 10 are stored in the cassette of the storage unit can be set freely, and the type of the cassette is a single wafer type (one wafer is used). Separate and store)
And stack type (wafers are stored one by one without being separated).

Further, when the wafer holding means of the second transfer section is provided with a function of rotating the wafer 10 by 90 ° in the circumferential direction, when the wafer 10 is stored in the cassette of the storage section, the orientation of the orientation flat or the notch can be reduced. Can be set freely.

[0016]

1, 2, and 3 show general views of an embodiment of a wafer cleaning slice-based peeling apparatus according to the present invention. 1 is a plan view, FIG. 2 is a view as viewed in the direction of the arrow J in FIG. 1 (front view), and FIG. 3 is a view as viewed in the direction of the arrow K in FIG. 1 (side view). The wafer cleaning slice-based peeling apparatus according to the present invention is roughly divided into a cleaning section 20, a drying / peeling section 30, a storage section 40, and a first transport section 5.
0 and a second transport unit 70, and are arranged as shown in FIGS.

The cleaning section 20 is for cleaning the wafer 10 sent from the cutting machine.
(Including a part of the first transport unit 50 described later). FIG.
Is a plan view, and FIG. 5 is a sectional view taken along line LL of FIG. The wafer 10 is shown by an imaginary line in FIG. 4 and by a solid line in FIG.

4 and 5, the washing section 20 has a washing tank 21 in which washing water is supplied at a predetermined height 22.
Although not shown, an ultrasonic generator is provided, although not shown. Further, the first transport unit 5 is provided in the cleaning tank 21.
A wafer guide 23 for guiding the base portion 10a when the wafer 10 is carried into the cleaning unit 20 by the number 0, and two wafer guides 24 for guiding the slice base 10b are also provided. Further, a holder 25 is fixed to the inner side surface of the cleaning tank 21, and a shaft 26 is attached to the holder 25.
Is mounted, and a roller 27 is rotatably supported on the shaft 26.

The drying / peeling part 30 is for drying the wafer 10 to which the water droplets are adhered after being cleaned by the cleaning part 20 and for peeling the slice base 10b from the base part 10a of the wafer 10; As shown in FIG. 7 is a front view (including a part of a second transport unit 70 described later), and FIG. 8 is a side view. FIG. 8 shows the wafer 10 in front of the drying nozzle, and FIG.

7 and 8, a drying nozzle 32 is attached to an upper end of a column 31. Drying nozzle 32
Dry air is blown out from a large number of holes 32a in a row facing obliquely downward, and the entire surface of one side (left side in FIG. 8) of the wafer 10 is dried by passing the wafer 10 in front of it.

A clamp base 34 is attached to an L-shaped flange 33 fixed to two upper and lower portions of the column 31 via a heat insulating plate 33a. The clamp table 34 has a built-in heater that generates heat at a predetermined temperature and a temperature sensor (both not shown) that detects the temperature of the clamp table 34, and is heated and held at a predetermined temperature (around 100 ° C.).

The shape of the contact surface 34a of the base portion 10a of the clamp table 34 is the same as that of the base portion 10a (circle).
The diameter is slightly smaller than the diameter of the base portion 10a. Two positioning bars 35 are provided below, and when the outer periphery of the base portion 10a abuts against the two positioning bars 35, the center of the base portion 10a substantially coincides with the center of the contact surface 34a. ing.

An air cylinder 36 with a built-in slide guide is attached to the column 31.
A pusher 37 is fixed to the slider 36a. Further, below the clamp table 34, the air cylinder 36, the pusher 37, and the like, a basket (not shown) provided below the apparatus base 11 is provided with a drop guide 38 that is peeled off and guides the slice base 10b. ing.

The storage section 40 is provided with a cassette on a table 41, and the wafer 10 from which the slice base 10b has been peeled off.
(That is, the base portion 10a) is stored. The cassettes include a sheet type and a stack type, and the cassette 42 shown in FIGS. 1, 2 and 3 is a stack type. In the stack type, the wafers 10 are stored so as to overlap each other, so that a larger number of wafers 10 can be stored as compared with the single wafer type.

The cassette 42 has a basic portion formed by connecting two side plates 42a with four bars 42b, and receives the outer periphery of the base member 10a with the four bars 42b. Further, three partition plates 4 are provided between the two side plates 42a.
2d is provided supported by the bar 42c. Further, a handle 42e is provided at the upper end of the two side plates 42a. As shown in FIG. 3, two spare cassettes 42 can be stored below the table 41.

The first transfer section 50 carries the wafer 10 sent from the cutting machine into the cleaning section 20 and carries out the washed wafer 10 from the cleaning section 20. The first transfer section 50 transfers the wafer 10 up and down. I do. As shown in FIGS. 1, 2 and 3, the first transport unit 50 has a vertical drive unit 51, and a first arm 52 attached to a slider of the vertical drive unit 51 is driven up and down. The vertical drive unit 51 is driven by screws using a servo motor as a drive source.

As shown in FIGS. 4, 5, and 6 (FIG. 6 is a sectional view taken along line MM of FIG. 4), a shaft holder 53 is attached to the tip of the first arm 52, and is fixed to the shaft holder 53. A support plate 55 is swingably supported on the shaft 54. Two support bars 56 extend from the lower side of the support plate 55, and two receiving plates 57 are fixed on the support bar 56 substantially at right angles to the support bar 56. A connecting plate 58 is fixed to one end of the two receiving plates 57, and a guide pin 59 is provided on the upper surface of the connecting plate 58.

A guide plate 60 is attached below the support plate 55 and above the support bar 56 in the same direction as the receiving plate 57. Further, a plate cam 61 is fixed to the surface of the support plate 55 opposite to the support bar 56, and a stopper 62 provided at the tip of the first arm 52 abuts on a projection 55 a at the upper end of the support plate 55. ing.

The cleaning is completed in the second transport section 70 and the cleaning section 20
After receiving the wafer 10 unloaded from the first transfer unit 50 and rotating the wafer 10 from the horizontal position to the vertical position,
Conveyed to the drying / peeling section 30
The wafer 10 from which 0b has been peeled is stored in the cassette 42 of the storage unit 40.

As shown in FIG. 1, FIG. 2, and FIG. 3, a horizontal drive unit 71 is provided in the second transport section 70, and a vertical drive unit 72 is provided upright on a slider of the horizontal drive unit 71, and a vertical drive unit 71 is provided. The second arm 73 attached to the slider 72 is driven vertically and in the Y direction. The horizontal drive unit 71 and the vertical drive unit 72 are driven by screws using a servo motor as a drive source.

As shown in FIGS. 7 and 8, a rotary cylinder 75 is attached to the tip of the second arm 73 via a bracket 74.
The arm 76 is rotatably supported at 90 °. At the tip of the arm 76, a suction pad 77 for vacuum-sucking the wafer 10 is attached so as to be movable in the Y direction in FIG. 8, and a preload is applied by a compression spring 78 in a direction away from the arm 76 (left direction in FIG. 8). Have been. The tip portion of the suction pad 77 is the same as in other embodiments of the wafer holding portion described later.

Next, the operation of the wafer cleaning slice-based peeling apparatus configured as described above will be described. Wafer 1
The main positions of 0 are denoted by reference numerals from A to Ib in FIG. 2, only the position of A is indicated by a solid line, and the others are indicated by imaginary lines.

When the first transfer unit 50 is at the rising end, the wafer 10 cut from the ingot by the cutting machine is placed in the horizontal position in the direction of the white arrow shown in FIG. The wafer 10 is unloaded onto the receiving plate 57 of the transfer section 50 (the wafer 10 is at the position A in FIG. 2). At this time, wafer 1
0 is guided on one side of the outer periphery by the guide plate 60 of the first transport section 50, and the other side is guided by the guide of the transport means of the cutting machine, and is carried out to a position where it abuts on the guide pin 59.

Next, the first transfer unit 50 descends, and the wafer 10 is carried into the cleaning unit 20. When the leading end of the first transfer unit 50 enters the cleaning tank 21, the receiving plate 57 moves horizontally. After gradually tilting to the maximum (the imaginary line in FIG. 5), it gradually returns to horizontal. That is, the lower side of the support plate 55 is
When the upper end of the cleaning tank 21 is concerned, the tip 61a of the plate cam 61 fixed to the support plate 55 does not contact the roller 27 provided in the cleaning unit 20, but the support plate 55 is lowered. Then, since the slope of the plate cam 61 comes into contact with the roller 27 and the support plate 55 is pressed, the support plate 55 is inclined leftward in FIG. This inclination angle is maximum when the peak 61b of the plate cam 61 contacts the roller 27.
When the support plate 55 further descends, the support plate 55 gradually returns to the right, and when it reaches the flat portion 61c of the plate cam 61, the support plate 55
Returns to the original position. Receiving plate 5 according to the movement of support plate 55
7 swings with respect to the horizontal.

Thus, even if there is nothing to press the upper surface of the wafer 10, the wafer 10 can enter the cleaning water without floating from the receiving plate 57. When the wafer 10 enters the cleaning water, the outer periphery is guided by the guide plate 60 and the guide pins 59 of the first transfer unit 50 and the wafer guides 23 and 24 of the cleaning unit 20.

When the wafer 10 enters the cleaning water (the wafer 10 is at the position B in FIG. 2), it is cleaned using ultrasonic waves. When the cleaning is completed, the first transfer unit 50 moves up to a position where the receiving plate 57 is near the upper end of the cleaning tank 21, and the wafer 10 is carried out from the cleaning water. At this time, the receiving plate 57 rises while swinging with respect to the horizontal similarly to the above-described loading (the order is reversed). Thereby, the wafer 10 can be cleaned.
Many water droplets adhering to the water are removed.

When the receiving plate 57 portion of the first transfer unit 50 comes near the upper end of the cleaning tank 21 (the wafer 10 is at the position C in FIG. 2), the wafer 10 is moved to the arm 76 at the tip of the second transfer unit 70. It is transferred to the suction pad 77 provided.

Next, the second transfer section 70 moves up and moves in the horizontal direction (left direction in FIG. 2) (the wafer 10 is at the position D in FIG. 2), and the arm 76 rotates 90 °. As a result, the wafer 10 is in the vertical posture (the position E in FIG. 2).

The vertical position of the wafer 10 is above the drying nozzle 32, and the wafer 10 descends as it is. When the wafer 10 reaches the descending end (position F in FIG. 2), it rises and returns to the original position. While returning to the original position from the lower end, the drying air is blown out from the drying nozzle 32 to dry one surface (the left surface in FIG. 2). The surface opposite to the drying nozzle 32 (the surface on the right side in FIG. 2) is dried by being heated at the time of peeling.

The positioning bar 35 is connected to the drying nozzle 32.
This is because even if the wafer 10 falls away from the suction pad 77 due to a trouble or the like, the wafer 10 keeps its normal position (the wafer 10 can be restarted from that position). The drying nozzle 32
2 is a position where the wafer 10 does not come into contact with the positioning bar 35.

After passing through the front of the drying nozzle 32, the wafer 10 is moved from the position E to the position G by the second transfer unit, and the center of the base 10a is moved therefrom to the clamp table 3.
4 is lowered along the clamp table 34 (without touching the clamp table 34) to a position slightly above the center of the contact surface 34a (before the outer periphery of the base portion 10a contacts the positioning bar 35).

Next, the holding force of the suction pad 77 is released, the outer periphery of the base portion 10a of the wafer 10 comes into contact with the positioning bar 35, and the center of the base portion 10a is brought into contact with the contact surface 34.
It almost coincides with the center of a. From this state, the second transport section further moves in the direction of the clamp table 34, and the suction pad 77 presses and fixes the substrate portion 10a against the clamp table 34 (position H in FIG. 2). The pressing force at this time is generated by the compression spring 78.

When a predetermined time elapses after the suction pad 77 fixes the base part 10a to the clamp table 34, the base part 1
Since the adhesive bonding the Oa and the slice base 10b becomes high temperature and becomes soft, the pusher 37 presses the slice base 10b in the thickness direction of the wafer 10 and separates it from the base portion 10a. The peeled slice base 10b falls, passes through the fall guide 38, and is stored in a basket (not shown).

The wafer 10 from which the slice base 10b has been peeled is transported to the storage section 40 by the second transport section 70 and stored in the cassette 42 (the wafer 10 is shown by I in FIG. 2).
a to Ib). In this case, the horizontal drive unit 71 of the second transport unit 70 is driven by screws using a servo motor as a drive source, and the feed amount can be freely set.
It is possible to store the wafers 10 in a stacked manner as in the stack type. Of course, it is needless to say that a single-wafer type can be used.

Next, another embodiment of the second transport section 70 will be described. In the other embodiment of the second transport unit 70, the suction pad rotates 90 °, and the horizontal drive unit 71, the vertical drive unit 72, the second arm 73, and the rotary cylinder 75 are the same as the above-described embodiment. The wafer holding portion is different. 10 is a front view, FIG. 11 is a side view, FIG. 12 is a cross-sectional view taken along a line P-P of FIG. 10 (detailed view of a suction pad portion), and FIG. Support portion).

In FIG. 10, FIG. 11, FIG. 12, and FIG. 13, a shaft 81a is fixed to a shaft holder 81 fixed to a rotary shaft of a rotary cylinder 75, and an arm holder 82 swings on the shaft 81a via a bearing 82a. The shaft holder 81 and the arm holder 8 are supported freely.
A tension spring 92 is hung between the two, and a preload is applied in one direction of the arm holder 82, and the rotation due thereto is regulated by a stopper 93.

The arm holder 82 has an arm 83.
And a pad holder 84 is attached to the tip of the arm 83.
Is attached. A suction pad 86 is rotatably supported on the pad holder 84 together with a timing gear 88, and the timing gear 88 is connected to a timing gear 91 fixed to a rotating shaft of a rotary cylinder 90 attached to the arm 83 by a timing belt 89. . A vacuum generator (not shown) is provided in the pad holder 84.
A tube 94 (not shown in FIGS. 10 and 11) is attached.

Thus, the suction pad 86 is rotated by 90 ° by the rotary cylinder 90. In this case, the suction pad 86 is connected to the clamp table 3 of the drying / peeling section 30.
The force for pressing the wafer 10 against 4 is generated by a tension spring 92.

Since the suction pad 86 rotates, a groove 86a is formed on the outer periphery of the suction pad 86 in a portion corresponding to the hole of the pad holder 84, so that suction can be performed regardless of the rotation position and air can be sucked. Packings 85 are provided at two places in the holes of the pad holder 84 so as not to leak. An O-ring 87 is attached to the tip of the suction pad 86 as generally configured.

[0050]

As described above, according to the wafer cleaning slice-based peeling apparatus of the present invention, cleaning, peeling,
A single device is provided with each function of storing, and the process from cleaning to storing of the wafer 10 is automatically performed. In addition, the adhesive softening method for peeling is performed by pressing the base material portion 10a against a clamp table having a built-in heater. In addition, the attitude of the wafer 10 is mainly set to the vertical attitude.

Therefore, the cleaning, peeling, and storing are automatically performed in a short time, the installation area is small, the cost is small, and the wafer cleaning slice base peeling is less likely to deteriorate the flatness of the wafer 10 and cause the occurrence of spots. An apparatus can be provided.

[Brief description of the drawings]

FIG. 1 is a plan view of an embodiment of a wafer cleaning slice-based peeling apparatus according to the present invention.

FIG. 2 is a view as viewed in the direction of arrow J in FIG. 1 (front view).

FIG. 3 is a view as viewed from an arrow K in FIG. 1 (side view).

FIG. 4 is a detailed plan view of a cleaning unit of the embodiment of the wafer cleaning slice-based peeling apparatus according to the present invention.

FIG. 5 is a sectional view taken along line LL of FIG. 4;

FIG. 6 is a sectional view taken along line MM of FIG. 4;

FIG. 7 is a detailed front view of a drying / peeling part of the wafer cleaning slice-based peeling apparatus according to the embodiment of the present invention.

FIG. 8 is a detailed side view of a drying / peeling part of the wafer cleaning slice-based peeling apparatus according to the embodiment of the present invention.

FIG. 9 is a view showing an outer shape of a wafer;

FIG. 10 is a front view showing another embodiment of the wafer holding means of the second transfer section of the wafer cleaning slice-based peeling apparatus according to the present invention.

FIG. 11 is a side view showing another embodiment of the wafer holding means of the second transfer section of the wafer cleaning slice-based peeling apparatus according to the present invention.

FIG. 12 is a sectional view taken along the line PP of FIG. 10 (detailed view of a suction pad portion);

FIG. 13 is a partial view taken along the line QQ in FIG. 11;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Wafer 20 ... Cleaning part 21 ... Cleaning tank 30 ... Drying / peeling part 32 ... Drying nozzle 34 ... Clamp table 40 ... Storage part 42 ... Cassette 50 ... First transport part 51 ... Vertical drive unit 52 First arm 57 Receiving plate 70 Second transport unit 71 Horizontal drive unit 72 Vertical drive unit 73 Second arm 77 Adsorption pad A Wafer carry-in position

Claims (4)

(57) [Claims] 1. A cleaning unit for cleaning a wafer after being cut from an ingot, and blowing dry air on the cleaned wafer;
A drying / peeling unit for fixing the wafer to a clamp table heated to a predetermined temperature and peeling the slice base adhered to the base part of the wafer, and a cassette for storing the wafer from which the slice base was peeled were provided. A storage unit, a first transfer unit that receives a wafer unloaded from the ingot cutting machine in a state where the thickness direction is vertical, loads the wafer into the cleaning unit, and unloads the wafer from the cleaning unit; and unloads the wafer from the cleaning unit. Received the wafer from the first transfer unit, after rotating the wafer in the thickness direction of the wafer in the horizontal direction, the wafer is carried into the drying and peeling unit,
And a second transfer unit that stores the wafer from which the slice base has been peeled in a cassette of the storage unit. 2. The wafer cleaning slice-based peeling apparatus according to claim 1, wherein the first transfer unit tilts the wafer when unloading the wafer from the cleaning unit. 3. The wafer cleaning slice base stripping apparatus according to claim 1, wherein the horizontal feed of the second transfer section is screw drive by a servomotor. 4. The apparatus according to claim 1, wherein the wafer holding means of the second transfer unit includes a mechanism for rotating the wafer by 90 ° in a circumferential direction.
A wafer cleaning slice-based peeling apparatus according to 4. [0001]