JPS62190729A - Washing apparatus - Google Patents

Abstract

PURPOSE:To improve the quality and the yield of a washing apparatus by forming the bottom of an overflow tank in an inverted conical shape, using a nozzle having an injection port of the same degree of injecting angle as the vertex of the inverted conical shape of the bottom of the tank as a drain valve, and mounting to bring the center of the port of the nozzle into coincidence with the vertex of the bottom of the tank to prevent dusts from being adhered to a wafer. CONSTITUTION:The bottom of an overflow tank 1 is formed in an inverted conical shape, and an exhaust port 2 is formed near the vertex of the inverted conical shape of the bottom of the tank 1. An injection nozzle 4 having a vertex equal to that of the inverted conical shape of the tank 1 at the injecting angle of the injection port is provided so that the vertex of the bottom of the tank and the center of the injection port are brought into coincidence with a drain valve 3 for opening and closing the port 2. The valve 3 is opened or closed by an elevator 6 to wash a carrier 7 contained in the tank and a wafer in the carrier 6. Pure water supplied from a pure water supply pipe 5 and injected from the injection nozzle at the bottom of the tank is advanced upward in a laminar flow, and contacted with an article such as a wafer to be washed without vortex near the injection port. Thus, the dusts removed by washing effect are regularly fed upward, exhausted out of the overflow surface, thereby always supplying clean pure water to the article to be washed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a water washing apparatus for semiconductor substrates used in a semiconductor device manufacturing process.

[Conventional technology]

Conventionally, in order to wash a substrate with water using this type of water washing device, cleaning water such as pure water or city water (hereinafter "pure water" will be explained as a representative example) is supplied from the bottom, side, or top of the overflow tank. This has generally been carried out by a method in which the semiconductor substrate (hereinafter referred to as a wafer) is washed with water by overflowing from the upper end, or a shower washing method in which pure water is sprayed from the upper part of the overflow surface.

FIG. 2 shows an example of a conventional water washing device. As shown in FIG. 2, pure water is sent from the pure water supply pipe 5 to the overflow tank 1, and the wafers (not shown) placed in the carrier 7 in an overflow state are washed with water. Overflow water and water in the tank were drained through a drainage pipe 8.

[Problem that the invention seeks to solve]

The conventional water washing equipment mentioned above connects the pure water piping directly to the bottom of the tank and supplies pure water, so the water flow from below does not flow upwards uniformly and generates a vortex near the water inlet, which causes problems during washing. However, there is a drawback in that dust once separated from the wafer or carrier accumulates due to the eddy current in the tank and re-adheres to the device forming surface of the wafer.

An object of the present invention is to provide a water washing device that reliably discharges dust from wafers or carriers to the outside of the tank.

[Means for solving problems]

The present invention provides a water washing device equipped with an overflow tank, a drain port provided at the inner bottom of the overflow tank, and a drain valve for opening and closing the drain port, in which the bottom of the overflow tank is formed in an inverted conical shape, and the bottom of the tank is A water washing device characterized in that a nozzle having a jetting opening with a jetting angle comparable to the apex angle of the inverted cone is installed in the drain valve so that the center of the jetting opening of the nozzle coincides with the apex of the bottom of the tank. be.

〔Example〕

Next, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a structural sectional view of one embodiment of the present invention.

In FIG. 1, the bottom of the overflow tank 1 is formed into an inverted conical shape, and a drain port 2 is provided near the apex of the cone at the bottom of the overflow tank 1 having the inverted conical shape, and a drain valve is provided to open and close the drain port 2. 3, the injection nozzle 4 whose injection angle is equal to the apex angle of the inverted cone of the overflow tank 1,
Install it so that the top of the tank bottom and the center of the injection port match. The drain valve 3 is opened and closed by an elevator 6, and the carrier 7 stored in the tank and the wafer inside the carrier 7 (not shown)
Wash with water.

As described above, the bottom of the overflow tank 1 is shaped like an inverted cone, and the injection nozzle with the same injection angle as the apex angle of the cone is installed so that the injection port coincides with the apex of the cone. The pure water supplied from 5 and injected from the injection nozzle at the bottom of the tank forms a laminar flow and advances upward.
Because the pure water comes into contact with the wafers and other objects to be washed without creating a vortex near the spout, the dust removed by the water washing effect is sent upwards in an orderly manner and is expelled from the overflow surface to the outside, ensuring clean pure water at all times. Enables to supply washed items. Furthermore, since there is a drain valve near the apex of the cone during draining, it is possible to remove dust that cannot be removed upwards even with the flow of pure water out of the tank along the conical surface during draining.

〔Effect of the invention〕

31 As explained above, the present invention can prevent dust from adhering to wafers, and therefore has a tremendous effect on improving quality and yield in the semiconductor device manufacturing process.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention, and FIG. 2 is a view showing a conventional water washing device. 1... Overflow tank, 2... Drain port, 3...
Drain valve, 4... Nozzle, 5... Pure water supply piping, 6.
...Elevator, 7...Carrier

Claims (1)

[Claims] (1) In a water washing device equipped with an overflow tank, a drain port provided at the bottom of the overflow tank, and a drain valve for opening and closing the drain port, the bottom of the overflow tank is formed in an inverted conical shape, and the bottom of the tank is A water washing device, characterized in that a nozzle having an injection opening with an injection angle comparable to the apex angle of the inverted cone is installed in the drain valve so that the center of the injection opening of the nozzle coincides with the apex of the tank bottom.