JPH0724264B2 - Semiconductor substrate washing equipment - Google Patents

Description

The present invention relates to an apparatus for washing a semiconductor substrate with water in a semiconductor manufacturing process.

[Conventional technology]

Conventionally, this kind of semiconductor substrate (hereinafter, referred to as a wafer) is washed with water by directly using ultrapure water (hereinafter referred to as pure water) supplied from an ultrapure water production apparatus.

FIG. 2 is a piping diagram of a device generally used conventionally. In FIG. 2, by opening the pure water supply valve 10, pure water of the flow rate set by the pure water supply valve 10 and the flow meter 11 is supplied from the bottom of the inner tank 12, and as a result, The inner tank 12 is filled with pure water, and the outer tank is
It overflows into 13 and is drained from the overflow pipe 14. Conventionally, in this state, the wafer 15 is put into the inner tank 12, immediately after which the pure water supply valve 10 is closed and at the same time the rapid drainage valve 16 is opened to complete drainage in a few seconds. Then, open the pure water supply valve 10 and at the same time close the quick drain valve 16,
The inner tank 12 becomes full. Rinsing was performed by repeating the water supply and drainage cycle.

[Problems to be Solved by the Invention]

The water washing effect mainly depends on the flow velocity and amount of pure water passing on the surface of the wafer, its specific resistance value, etc. Since it depends on the pressure and flow rate of pure water supplied,
Limited by the pure water purification capacity of semiconductor manufacturing plants. Therefore, when the pure water purification capacity is insufficient, it takes a long time from the completion of drainage until the water is full, so that there is a disadvantage that etching of the wafer and adhesion of dusts are caused by the residual liquid on the wafer.

The object of the present invention is to solve the above-mentioned drawbacks, and not only by the pure water purification capacity of a semiconductor manufacturing plant, but by a drop from a water storage tank,
It is an object of the present invention to provide a semiconductor substrate rinsing apparatus capable of instantaneously completing water supply to a processing tank and further supplying water to a normal processing tank via a water storage tank.

[Means for Solving the Problems]

According to the configuration of the present invention, in a semiconductor substrate rinsing apparatus including a cleaning layer for cleaning a semiconductor wafer with pure water and a water tank for storing the pure water supplied into the cleaning layer, the cleaning layer is treated. An inner tank containing the semiconductor wafer and an outer tank into which the pure water overflowing in the inner tank flows, and the water storage tank is at a position where there is a drop necessary for supplying water to the inner tank, and A pipe having a layer that stores at least an amount of pure water equal to the capacity of the inner tank, and a pipe for supplying water into the inner tank from the water reservoir by the drop, a water supply valve provided in the pipe, and the water tank An inlet port is located on the wave surface when storing more than the amount of pure water in the inner tank, and an overflow pipe for supplying water to the inner tank and a drain valve for draining the pure water in the inner tank are provided. And

〔Example〕

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

FIG. 1 is a piping diagram of a semiconductor substrate washing apparatus according to an embodiment of the present invention. In the figure, this embodiment is necessary because the flow meter 3 monitors the flow rate when the feed water supply valve 1 feeds pure water from the ultrapure water producing apparatus in the factory to the water storage tank 2. The water tank 2, the quick water supply valve 4, and the water supply pipe 5 are
The pure water in the water storage tank 2 can be supplied to the inner tank 6 in a few seconds, and the overflow pipe 7 is used to supply the pure water overflowing from the water storage tank 2 to the inner tank 6. The quick drain valve 8 is for draining the pure water in the inner tank 6 in a few seconds. The outer tank 9 is for collecting and draining the pure water overflowing from the inner tank 6.

In this semiconductor substrate rinsing apparatus, by constantly supplying water to the water storage tank 2, pure water overflowing from the water storage tank 2 is supplied to the inner tank 6 through the overflow pipe 7, and the inner tank 6 becomes full and overflows. With the pure water flowing into the outer tank 9 and being drained, the quick drain valve 8 is opened, and the pure water in the inner tank 6 is completely drained in a few seconds, and at the same time, the quick drain valve 8 is closed and the quick water supply valve is opened. By opening 4, the water supply to the inner tank 6 is completed in a few seconds, and this state is maintained until the water washing is completed. After the completion of washing with water, the quick water supply valve 4 is closed and the initial state is controlled.

〔The invention's effect〕

As described above, according to the present invention, the time of exposing a wafer to the atmosphere is minimized by performing the drainage and the water supply immediately after the wafer is put into the tank, and the deionized water supply capacity of the deionized water producing apparatus is insufficient. Has the effect of minimizing the amount of water, and since pure water can be added after draining all pure water that has been contaminated to some extent, there is also the effect that the pure water in the inner tank can be kept at a high purity. .

[Brief description of drawings]

FIG. 1 is a piping diagram of a semiconductor substrate washing apparatus according to an embodiment of the present invention, and FIG. 2 is a piping diagram of a conventional semiconductor substrate washing apparatus. 1,10 …… Pure water supply valve, 2 …… Water tank, 3,11 …… Flowmeter, 4 …… Rapid water supply valve, 5 …… Water supply pipe, 6,12 …… Inner tank, 7,14… … Overflow piping, 8,16 …… quick drain valve, 9,13 …… outer tank, 15 …… semiconductor wafer.

Claims (1)

[Claims] 1. A semiconductor substrate rinsing apparatus comprising: a cleaning tank for cleaning a semiconductor wafer with pure water; and a water tank for storing the pure water supplied into the cleaning tank.
It has an inner tank into which the semiconductor wafer to be processed and an outer tank into which the pure water overflowed in the inner tank flows, and the water storage tank is at a position where there is a drop necessary for supplying water to the inner tank. And a pipe for storing pure water in an amount at least equivalent to the capacity of the inner tank, and a pipe for supplying water from the water reservoir into the inner tank by the drop, a water supply valve provided in the pipe, and the water reservoir An inlet pipe is located on the liquid surface when storing more than the amount of pure water in the inner tank, and an overflow pipe for supplying water to the inner tank and a drain valve for draining the pure water in the inner tank are provided. A semiconductor substrate washing apparatus characterized by the above.