JPH07183268A - Washer of semiconductor wafer - Google Patents

Abstract

PURPOSE:To considerably reduce the number of particles left on and attached to a wafer surface after washed by chemical liquid and improve a manufacturing yield of semiconductor device products. CONSTITUTION:Sequentially from leftwardly, a first chemical bath 1 receiving NH liquid 7 (mixed liquid of ammonia water, a hydrogen peroxide solution, and pure water), a pure rinsing bath 2 receiving pure water of 80 deg.C, a second chemical liquid bath 3 receiving the NH liquid 7 being the same chemical liquid as the first chemical liquid bath 1, a pure rinsing bath 4 receiving pure water of 80 deg.C, and a drier 5 are continuously provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor wafer cleaning apparatus.

[0002]

2. Description of the Related Art In the process of manufacturing a semiconductor device such as an LSI, fine particles attached to the surface of a semiconductor wafer, which is a base material of the semiconductor device, are a major cause of defective products and deterioration of product yield. Therefore, in the cleaning process, which is the final process of manufacturing semiconductor wafers, two identical chemical baths are provided in succession, the wafers are immersed in the same chemical twice for cleaning, and then rinsed in a pure water bath. The device is in use.

[0003]

However, in the above apparatus, in the first chemical bath, some of the particles that have been once removed from the surface of the wafer and are suspended in the chemical are regenerated when the wafer is pulled up. Since they adhere and are brought into the second chemical bath, the floating particles for two baths adhere to the wafer lifted from the second chemical bath, and only the final rinse with pure water removes them. There was a problem that I could not cut it. In view of the above problems, the present invention provides a semiconductor wafer cleaning apparatus capable of significantly reducing the number of particles remaining on the surface of a wafer after chemical cleaning and improving the product yield of semiconductor devices. The purpose is to do.

[0004]

Therefore, in the present invention, two or more identical chemical solution tanks are continuously provided, and a rinse tank is provided between the chemical solution tanks.

[0005]

When the semiconductor wafer is cleaned by this apparatus, floating particles attached when the first chemical bath is pulled up are pure rinse tanks provided between the first chemical bath and the second chemical bath. Since it is removed in the water rinsing tank, the amount of particles brought into the second chemical liquid tank can be reduced.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a vertical cross-sectional view showing the structure of a semiconductor wafer cleaning apparatus according to the present invention, FIG. 2 is a vertical cross-sectional view showing the structure of a conventional cleaning apparatus, and FIG. It is a graph which shows comparative data.

As shown in FIG. 1, the cleaning apparatus according to the present invention comprises a first chemical bath 1, a pure water rinsing bath 2, and a second bath in order from the left.
The chemical solution tank 3, the pure water rinsing tank 4 and the dryer 5 are continuously formed, and a pure water rinsing tank is added between the same chemical solution tanks of the conventional cleaning device as shown in FIG. .

As shown in FIG. 1, the wafer 6 is prepared by first mixing a mixed liquid 7 of ammonia water, hydrogen peroxide water and pure water (hereinafter, referred to as N).
The H liquid 7) is immersed in the first chemical bath 1 containing the H liquid 7 for cleaning, and the particles 8 adhering to the surface of the wafer 6 are removed by the etching action of the NH liquid 7. At that time, in the chemical solution tank 1, a part of the particles 8 which are once removed from the wafer surface and remain in the chemical solution and are floating are reattached when the wafer 6 is pulled up. Particle 8
The wafer 6 re-attached to is transferred to the pure water rinsing tank 2 in which pure water of 80 ° C. is stored, which is a rinse tank, is immersed, and is rinsed and washed. At that time, the particles 8 adhering to the surface of the wafer 6 are peeled and removed. Here, the pure water rinsing tank 2 is an overflow tank, and the particles 8
The water contaminated by the removal of the water is cleaned and circulated through a filter (not shown) provided on the outside to reduce the re-adhesion of the particles 8 to the wafer 6. . Next, after the particles 8 adhering to the surface of the wafer 6 are removed again after being transferred to the second chemical liquid tank 3 in which the NH liquid 7 which is the same chemical liquid as the first chemical liquid tank 1 is stored and immersed. It is rinsed again in the pure water rinse tank 4 and finally dried by the dryer 5. As described above, the transfer of the wafer 6 in the above process is performed by the wafer carrier (not shown) loaded and the automatic carrier transfer mechanism.
The NH liquid used in the above cleaning apparatus may be one in which ozone is injected instead of the hydrogen peroxide solution contained therein, and a sufficient etching effect can be obtained.

FIG. 3 is data showing the effect of the present embodiment. The number of particles deposited on the submicron order after the wafer 6 is dried is smaller than that of the conventional cleaning apparatus when the pure water in the pure water rinsing tank 2 is at room temperature. In the case of 80 ° C. hot water, it was reduced to less than one fifth.

In the above embodiment, the temperature of the pure water in the pure water rinsing tanks 2 and 4 is 80 ° C., but the temperature is not limited to this, and may be 40 ° C. or higher. Exfoliation of particles becomes active. Further, by applying ultrasonic vibration to the pure water rinse tanks 2 and 4, a further peeling effect can be obtained.

[0011]

The semiconductor wafer cleaning apparatus according to the present invention has the following effects. The number of particles remaining on the surface of the wafer after chemical cleaning can be significantly reduced to about 1/5 or less of that of the conventional apparatus, and the product yield of semiconductor devices can be improved.

[0012]

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing a configuration of a semiconductor wafer cleaning apparatus according to the present invention.

FIG. 2 is a vertical cross-sectional view showing the configuration of a conventional cleaning device.

FIG. 3 is a graph showing comparison data of the number of adhered particles in the present invention and the conventional device.

[Explanation of symbols]

1 First Chemical Solution Tank 2 Pure Water Rinse Tank (Rinse Tank) 3 Second Chemical Solution Tank 4 Pure Water Rinse Tank (Rinse Tank) 5 Dryer 6 Wafer 7 NH Liquid (Ammonia Water, Hydrogen Peroxide Water, and Pure Water Mixed solution)

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tadashi Ogawa 1112 Kihara, Kiyotake-cho, Miyazaki-gun, Miyazaki Prefecture Komatsu Electronics Co., Ltd.

Claims (8)

[Claims] 1. A semiconductor wafer cleaning apparatus characterized in that two or more same chemical baths are continuously provided, and a rinse bath is provided between the chemical baths. 2. The semiconductor wafer cleaning apparatus according to claim 1, wherein the chemical bath is a mixed bath of ammonia water, hydrogen peroxide water and pure water. 3. The semiconductor wafer cleaning apparatus according to claim 1, wherein the chemical bath is a mixed bath of ammonia water, ozone and pure water. 4. The semiconductor wafer cleaning apparatus according to claim 1, wherein the rinse tank is a pure water rinse tank. 5. The semiconductor wafer cleaning apparatus according to claim 4, wherein the pure water in the pure water rinsing tank is hot water. 6. The semiconductor wafer cleaning apparatus according to claim 4, wherein the temperature of the pure water in the pure water rinsing tank is 40 ° C. or higher. 7. The semiconductor wafer cleaning apparatus according to claim 1, wherein the rinse tank is an overflow tank. 8. The cleaning apparatus for a semiconductor wafer according to claim 1, wherein ultrasonic vibration is applied to the rinse tank.