JPS63275112A - Wafer conveying equipment - Google Patents

Abstract

PURPOSE:To reduce the amount of dust leaking outward, and prevent the contamination of a wafer surface due to dust, by providing a wheel and a bottom surface with covers. CONSTITUTION:A plurality of wheel covers 4 and a plurality of bottom surface covers 5 are provided. Those cover the upper surface of wheels except a wheel 2 of one end-portion of a main body part 1, and are fixed to the main body part 1. These are fixed to the bottom surface of the main body part 1 between the wheels 2. The wheel covers 4 cover the wheel 2 in the manner in which the external upper surface of the wheel 2 with an external diameter of about 45mm is covered with a several mm gap. The bottom surface covers 5 cover about 1/4 part of the lower side part of the external pheriphery of a wafer 8 with an external diameter of 6 inches. Therefore, dust generated by the wheel 2 can be prevented from attaching to the wafer 8 mounted on a boat 7 by the wheel covers 4. The dust blown up by travelling can be prevented from attaching to the wafer 8 by the existence of the bottom surface covers 5.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a wafer transport device, and more particularly to a wheeled wafer transport device for a horizontal wafer diffusion furnace.

[Conventional technology]

Conventionally, this type of wafer transport equipment has a structure in which it can be moved on multiple wheels by mounting multiple boats on which multiple wafers can be loaded vertically, and the main body is rotatably supported between frames. It was made up of wheels.

[Problem that the invention seeks to solve]

The above-mentioned conventional wafer transport device has the drawback that the bottom side, wheels, and axle are exposed to the wafer on which the wafer is mounted, so that dust can fly up and adhere to the wafer surface.

[Means for solving problems]

The wafer transport device of the present invention includes a main body portion having a plurality of wheels on which a plurality of boats carrying a plurality of wafers are mounted, and a wheel cover provided to cover the upper surface of the wheels; and a bottom cover provided to cover between the wheels on the bottom side of the main body.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIGS. 1(a) and 1(b) are a plan view and a side view, respectively, of an embodiment of the present invention.

As shown in FIG. 1, a framed main body 1, a plurality of wheels 2 rotatably supported on the main body 1 by an axle 3,
A plurality of wheel covers 4 are fixed to the main body 1 so as to cover the upper surfaces of the wheels 2 except the wheels 2 at one end of the main body 1, and a plurality of wheel covers 4 are fixed between the wheels 2 on the bottom side of the main body 1. A pull-out rod η fixed to one end of the main body 1 includes a frame 6, and a hook for pulling out the furnace.

The wheel cover 4 covers the upper surface of the outer periphery of the wheel 2 having an outer diameter of 45 InI11 with an interval of several mm. The bottom cover 5 covers about 1/4 of the lower part of the outer periphery of the wafer having an outer diameter of 6 inches, and its cross-sectional shape is curved in an arc shape to match the shape of the wafer. The distance between the wafer and the bottom cover 5 is 10 to 20 mm.

If the wafer transport equipment becomes heavy, the friction of the wheels 2 will increase and the amount of dust generated will increase. Therefore, it is desirable that the thickness of the wheel cover 4 and the bottom cover 5 be as thin as possible within the range that mechanical strength allows. In the example, it was set to 2 to 3 Il1m.

Next, FIG. 2 is a perspective view of a wafer transport device for explaining the state of transporting a wafer using the embodiment shown in FIG.

As shown in FIG. 2, a plurality of boats 7 each carrying a plurality of wafers 8 in an upright position are mounted on the upper surface of the main body 1. The main body 1 is moved through the furnace by hooking a pull-out rod 9 to a frame 6.

The wheel cover 4 prevents dust generated by the wheel 2 from adhering to the wafers 8 placed on the boat 7. Further, the bottom cover 5 prevents dust that flies up during movement from adhering to the wafer 8.

3(a) and 3(b) are perspective views of a wafer carrier test jig for testing the amount of dust collected when using the embodiment of FIG. 1, respectively.

As shown in FIG. 3(a), the wafer transport device of this example was moved on a quartz saucer 10 having an arcuate cross section, and the dust generated was collected. Further, as shown in FIG. 3(b), dust generated by moving this example in a cylindrical tube 11 made of quartz was collected. However, in the latter case, nitrogen gas is sprayed in the direction of movement.

Figures 4(a) and (b) correspond to Figures 3(a) and (), respectively.
FIG. 3 is a characteristic diagram showing a comparison between the amount of dust collected as a result of the dust collection test in b) and the amount of dust generated by a conventional wafer transport device.

In Figure 4, the moving speed of the wafer transport device is 40c.
m/min, and the velocity of the nitrogen gas flow in FIG. 4(b) is 60 cm/min.

As shown in FIG. 4(a), the amount of dust collected in this embodiment is significantly reduced compared to the conventional wafer transport device without a cover. In addition, as shown in Figure 4 (b), in the latter test, the amount of dust collected increased due to the increase in the amount of dust thrown up by the nitrogen gas flow, but compared to the conventional one without a cover. It has decreased significantly.

〔Effect of the invention〕

As described above, the present invention has the effect of preventing contamination of the wafer surface by dust, since the amount of dust leaking to the outside can be reduced by providing a cover on the wheels and the bottom side.

[Brief explanation of drawings]

1(a) and (b) are respectively a plan view and a side view of an embodiment of the present invention, and FIG. 2 is a wafer transport device for explaining the state of transporting a wafer using the embodiment of FIG. 1. Figures 3(a) and (b) are respectively perspective views of a wafer carrier test jig for testing the amount of dust collected when using the embodiment of Figure 1, and Figure 4(a). a) and (
b) is a characteristic diagram showing a comparison between the amount of dust collected as a result of the dust collection test of FIGS. 3(a) and 3(b) and the amount of dust generated by a conventional wafer transport device. 1... Main body, 2... Wheels, 3... Axle, 4...
・Wheel cover, 5...Bottom cover, 6...Hook is frame, 7...Boat, 8...Wafer, 9...Drawer rod, 10...Saucer, 11...Cylindrical tube .

Claims (1)

[Claims] A wafer transport device comprising a main body having a plurality of wheels on which a plurality of boats carrying a plurality of wafers are mounted, a wheel cover provided to cover the top surface of the wheels, and a wheel cover provided on the bottom surface side of the main body. A wafer transport device characterized by having a bottom cover provided to cover between the wheels.