JP2609817B2 - Semiconductor wafer transfer equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor wafer transfer apparatus, and more particularly to a semiconductor wafer transfer apparatus of a semiconductor manufacturing apparatus for performing batch processing.

[0002]

2. Description of the Related Art As a typical batch processing apparatus, a vertical CVD apparatus and a vertical diffusion furnace apparatus are particularly exemplified. In each case, 50 to 150 semiconductor wafers per batch are heated in a furnace to perform required film formation or diffusion. As shown in FIG.
It is supported by the boat 2 and processed in the furnace.

The semiconductor wafer transfer apparatus performs a series of operations for transferring the semiconductor wafers 1 loaded in the cassette 3 to the boat 2 and returning the processed semiconductor wafers 1 to the empty cassette 3.

[0006] The semiconductor wafer transfer apparatus shown in FIG. 6 includes a single-wafer plate 4 (one for transferring one by one) and a batch plate 5.
(Several pieces are transferred at once). Further, the batch plate 5 has a pitch conversion mechanism so as to have an arbitrary pitch starting from the single-wafer plate 4. In the pitch conversion method, each plate is connected to a screw rod having a different lead, and each plate is slid by the screw rod to obtain a movement amount corresponding to the position of the plate.

FIG. 7 is a view showing a transfer example using the conventional semiconductor wafer transfer apparatus. The cassette 3 is provided by a single plate 4 and a batch plate 5 having four plates.
When transferring nine semiconductor wafers 1 from the boat to the boat 2,
First, five wafers are transferred at one time by the single-wafer plate 4 and the batch plate 5. From the second time on, only the single wafer plate 4 is used to transfer the remaining wafers one by one four times.

In such a semiconductor wafer transfer apparatus, it is most efficient to transfer a wafer which is a multiple of the total number of plates (the number of plates that can be transferred at one time).

[0007]

In this conventional semiconductor wafer transfer apparatus, the number of wafers transferred at one time is fixed, and a fraction of semiconductor wafers is
Must be transferred one at a time.

Accordingly, when the cassette 3 is loaded with a fractional number of semiconductor wafers, nine semiconductor wafers need to be transferred five times in FIG. 7 as an example.
Very inefficient.

In the case of a batch processing apparatus, when the number of cassettes loaded with a fractional number of semiconductor wafers increases, the time required for transferring semiconductor wafers directly affects the processing capacity of the apparatus.

The above-described example is common in a manufacturing line in which a large number of semiconductor wafers of the same type do not flow, and the inefficient operation of the conventional transfer method causes a reduction in processing capacity. there were.

Accordingly, an object of the present invention is to provide a semiconductor wafer transfer apparatus capable of efficiently transferring semiconductor wafers regardless of the number of semiconductor wafers.

[0012]

A feature of the present invention is that in a semiconductor wafer transfer apparatus provided with a required number of plates for transferring semiconductor wafers, a predetermined plate except for the uppermost or lowermost plate among the plates is used as a semiconductor wafer transfer device. There is a semiconductor wafer transfer device which can be removed from the plate insertion direction at the time of wafer transfer by rotating a swivel ring. Here, the turning ring is connected to a turning gear, and rotation of the turning ball spline is transmitted to the turning ring via the turning gear, whereby the turning ring can be rotated. Alternatively, the plurality of plates are respectively coupled to the plate base via the turning ring, and different screw rods are respectively connected between the plurality of plate bases, and by simultaneously rotating the plurality of screw rods. The distance between the plates can be changed at equal intervals. Here, the plurality of screw rods are respectively connected to one pitch conversion ball spline via a gear mechanism, and by rotating the pitch conversion ball spline, the intervals between the plates can be changed at equal intervals. preferable.

[0013]

As described above, since the rotating mechanism which can remove a predetermined plate from the plate inserting direction is provided, the transfer operation can be performed with the number of plates corresponding to the number of semiconductor wafers to be transferred. The transfer operation can be performed efficiently regardless of the number of transferred semiconductor wafers. Further, since a practical pitch conversion mechanism can be combined with the above-mentioned turning mechanism, the pitch between the plates can be adjusted to the pitch of the boat or the cassette and converted to a desired number of plates.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described with reference to the drawings. FIG. 1 is an external functional diagram of a semiconductor wafer transfer device according to one embodiment of the present invention.

The uppermost sheet plate 4 is a plate at the starting point of the pitch conversion while facing the plate insertion direction at the time of transfer. The four rotating plates 6 thereunder can freely and independently rotate as needed, retreat the plate from the insertion direction, and can change the pitch starting from the uppermost sheet plate. This starting plate may be at the bottom.

FIG. 2 is a diagram showing a transfer example in the wafer transfer device of FIG. Single plate 4 and swivel plate 6
When nine semiconductor wafers 1 are transferred from the cassette 3 to the boat 2 with a plurality of wafers, first, the single wafer plate 4 and the revolving plate 6 are used to transfer five wafers at a time.
In the second time, since there are four wafers remaining, one of the revolving plates 6 revolves and retreats from the insertion direction, and the single-wafer plate 4
Then, the rotation plate 6 transfers three wafers at a time to four wafers. Thus, the transfer of nine semiconductor wafers can be completed by two transfers.

Next, the mechanism of the embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIGS.

First, the pitch conversion mechanism will be described with reference to FIG. Central pitch conversion ball spline 7
As shown in FIG. 3A, a shaft having a cross-sectional shape in which a large number of irregularities are formed, and the pitch conversion main gear 11 is coupled thereto. Therefore, the pitch conversion main gear 11 rotates with the rotation of the pitch conversion ball spline 7 and is slidable in the axial direction (vertical direction) of the pitch conversion ball spline 7. That is, although the rotational force is transmitted by the pitch converting ball spline 7, the ball can be slid freely in the axial direction (vertical direction).

The uppermost plate base 14F of the plate bases 14 is fixed, and the lower plate base 1 is fixed.
4A and 14B are able to move up and down together with the respective pitch conversion main gears 11. However, the pitch conversion main gear 11 and the plate base 14 are
The rotation of the pitch conversion main gear 11 is not transmitted to the plate base 14.

When the pitch converting ball spline 7 rotates, the pitch converting main gear 11 (11A) also rotates.
The rotation of the pitch conversion main gear 11 connected to the uppermost plate base 14F via a bearing 18 rotates the pitch conversion gear 10 that is gear-coupled to the main gear 11 and is fixed by the pitch conversion gear 10 and the set screw 19. The screw rod 9A is rotated. The screw rod 9A is connected to the plate base 14 via a bearing 18.
F and the male screw is the second stage plate base 14
Since the female screw member 21 fixed to A is screw-coupled, the rotation of the screw rod 9A causes the plate base 14A to move up and down with respect to the plate base 14F.
For example, by moving the plate base 1 downward,
The interval, that is, the pitch between the single-wafer plate 4 (FIG. 1) connected to 4F and the revolving plate 6 (FIG. 1) connected to the plate base 14A increases.

When the plate base 14A moves downward, the pitch conversion main gear 11 (11B) bearing-coupled thereto also moves downward, and the pitch conversion main gear 11 (11B) also rotates the pitch conversion ball spline 7. , And the pitch conversion gear 10 that is in gear connection with the rotation rotates.
And the screw rod 9B fixed by the set screw 19 rotates. Screw rod 9B is bearing 1
8, the male screw penetrates through the plate base 14A and is screwed to the female screw member 21 fixed to the third-stage plate base 14B.
Due to the rotation of B, the plate base 14B moves downward with respect to the plate base 14A. Thereby, the swivel plate 6 (FIG. 1) connected to the plate base 14A and the swivel plate 6 (FIG. 1) connected to the plate base 14B.
, That is, the pitch between the revolving plate 4 connected to the plate base 14F and the revolving plate 6 connected to the plate base 14A is also widened.

As described above, each base plate 14 moves downward or upward by the same distance with respect to the plate base immediately above (with reference to the plate base immediately above). The pitch between the plates, which are fixed at the same, can be increased or decreased with the same value.

Next, the turning mechanism of the turning plate will be described with reference to FIG. Here, the turning mechanism coupled to the third plate base 14B from the top will be described as an example, but the same rotating mechanism coupled to other plate bases (except the uppermost step) may be provided at other positions on the circumference. It is placed.

The turning ball spline 8 is shown in FIG.
As shown in FIG. 5, a shaft having a cross-sectional shape in which a number of irregularities are formed, in which a turning gear 12 and other support members 22 of a plate base rotate together with the rotation of the turning ball spline 8, and 8 is slidable in the axial direction (vertical direction).

The rotation of the turning ball spline 8 causes the turning gear 12 to rotate, and the turning ring 13 rotating as the internal gear with the turning gear 12 and the gear coupling 23 rotates. Since the turning ring 13 is connected to the side surface of the plate base 14B by the ball bearing 21 and makes a round around the outside of the side surface of the plate base 14B, the rotation of the turning ring 13 causes the turning plate 6 of the plate base 14B to move to the front position. (The right side position as shown in FIG. 4B) can be turned to the rearward position (the left side position in FIG. 4B). The support member 22 connected to the other plate base 14A by the bearing mechanism 18 is only rotating while supporting the turning ball spline 8.

FIG. 5 shows a wafer transfer apparatus according to the embodiment. In FIG. 5, the parts having the same functions as those in FIGS. 3 and 4 are denoted by the same reference numerals, and the duplicate description will be omitted. 5A is a plan view, and FIG. 5B is a plan view of FIG.
It is sectional drawing of CDEA part.

Below the uppermost plate base 14F to which the single-wafer plate 4 is connected and fixed, four vertically movable (four-stage) plate bases 14 connected to the respective swivel plates 6 are arranged. I have.

A pitch conversion mechanism shown in FIG. 3 having a pitch conversion gear 10 and a screw rod 9 at two target positions a, a, a from the center in FIG. The distance between the plate base 14F and the second-stage plate base 14, that is, the pitch between the single-wafer plate 4 and the revolving plate 6, is converted to a predetermined value.

Similarly, the pitch between the second and third revolving plates 6 is changed by a pair of pitch conversion mechanisms at two positions b and b, and the pair of pitch conversion mechanisms at two positions c and c is used. By converting the pitch between the third and fourth turn plates 6,
Fourth stage and fifth stage by a pair of pitch conversion mechanisms at two positions d and d
The pitch between the revolving plates 6 at the lowermost stage is converted.

Then, as described with reference to FIG. 3, the pitch converting ball spline 7 is driven by the pitch converting motor 15.
Further, the main gears 11 for pitch conversion are rotated, and the plate bases 14 of the second and subsequent stages are simultaneously moved up and down so that each pitch has the same predetermined value.

On the other hand, at positions a ', b', c 'and d' on the outer circumference of the pitch conversion mechanism, the turning mechanism described in FIG. 4 having the turning ball spline 8 and the turning gear 12 is provided. It is placed.

The turning plates 6 connected to the second, third, fourth and fifth plate bases are turned by the turning mechanisms at positions a ', b', c 'and d', respectively. Therefore, by turning the turning ball spline 8 of the step to be turned, the turning ring 13 turns only in that step, and the turning plate 6 attached to the turning ring 13 is rotated.
Turns. In the cross-sectional view of FIG. 5B, a turning mechanism for turning the turning plate 6 connected to the fourth stage plate base is shown on the right side, and a turning mechanism for turning the turning plate 6 connected to the second stage plate base on the left side. The mechanism is shown. Swivel ring 1 to be connected to the swivel plate to be swiveled
In order to rotate 3, the corresponding turning ball spline 8 is turned by the turning drive belt 16. Except for the top stage, all the plate bases 14 at each stage hold the respective gears via ball splines, so that the pitch conversion and turning functions are not lost.

[0033]

As described above, according to the present invention, the number of semiconductor wafers transferred at one time is made variable within the number of plates provided in the semiconductor wafer transfer device, so that the transfer efficiency can be maintained even if the number of semiconductor wafers changes. Has the result that it does not drop.

Also, since the pitch at the time of batch is made variable,
There is also a result that even when the semiconductor wafer storage pitch is changed, it can be easily handled.

[Brief description of the drawings]

FIG. 1 is a diagram showing an external function of a semiconductor wafer transfer device according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating a transfer example using the semiconductor wafer transfer device according to the embodiment of the present invention.

FIG. 3 is a diagram showing a pitch conversion mechanism in the semiconductor wafer transfer device according to the embodiment of the present invention.

FIG. 4 is a view showing a turning mechanism in the semiconductor wafer transfer device according to the embodiment of the present invention.

FIG. 5 is a diagram showing an entire mechanism of the semiconductor wafer transfer device according to the embodiment of the present invention.

FIG. 6 is a diagram showing an external function of a conventional semiconductor wafer transfer apparatus.

FIG. 7 is a diagram illustrating a transfer example using the semiconductor wafer transfer device of FIG. 6;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Semiconductor wafer 2 Boat 3 Cassette 4 Single plate 5 Batch plate 6 Revolving plate 7 Ball spline for pitch conversion 8 Ball spline for rotation 9, 9A, 9B Screw rod 10 Gear for pitch conversion 11, 11A, 11B Main gear for pitch conversion 12 Swivel gear 13 Swivel ring 14, 14F, 14A, 14B Plate base 15 Pitch conversion motor 16 Swivel drive belt 17 Gear coupling 18 Bearing mechanism 19 Set screw 20 Screw coupling 21 Ball bearing 22 Support member 23 Gear coupling

Claims (4)

(57) [Claims] In a semiconductor wafer transfer apparatus provided with a required number of plates for transferring semiconductor wafers, a predetermined plate except for an uppermost stage or a lowermost stage of the plates is placed in the direction of plate insertion when transferring the semiconductor wafer. A semiconductor wafer transfer device characterized in that it can be removed by rotating a turning ring. 2. The turning ring is coupled to a turning gear, and rotation of a turning ball spline is transmitted to the turning ring via the turning gear, whereby the turning ring rotates. 2. The semiconductor wafer transfer device according to claim 1, wherein: 3. The plurality of plates are respectively connected to the plate base via the swivel ring, and different screw rods are connected between the plurality of plate bases, and the plurality of screw rods are simultaneously rotated. 2. The semiconductor wafer transfer device according to claim 1, wherein the distance between the plates can be changed at an equal interval. 4. A plurality of said screw rods are respectively connected to one pitch conversion ball spline via a gear mechanism, and said plates are variable at equal intervals by rotating said pitch conversion ball spline. 4. The semiconductor wafer transfer device according to claim 3, wherein