JPH04155925A - Wet etching device - Google Patents

Abstract

PURPOSE:To prevent a trouble that bubbles, which are generated in an etching remaining as the surfaces of semiconductor wafers come into contact to the sidewalls of grooves in a magazine case, intrude in between both of the wafer surfaces and the sidewalls of the grooves and the wafers stand still, to eliminate an etching residue without inhibiting the etching and to improve the yield of the wafers by a method wherein a rotator, which comes into contact to the wafers and gives a rotating motion to these wafers, is mounted at the bottom of an etching tank. CONSTITUTION:A rotating axis 7 is arranged over a base plate 2 in such a way as to penetrate the wall of an etching tank 1 and is coupled with a pulse motor. The axis 7 is provided with a plurality of discs 8. A magazine case 3 with semiconductor wafers 4 housed therein is dipped in a chemical and is put on the base plate 2. The wafers 4 are housed in such a way that their orientation flats come to the bottom of the case 3. The position of the rotating axis is set in such a way that the discs come into contact to the orientation flats of the wafers and the wafers are pushed up a little by the discs. The rotating axis is rotated by the pulse motor and the wafers are made to swing. Thereby, it is prevented that bubbles intrude into between the wafers and the wall surfaces of grooves in the case 3 and the wafers stand still.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a wet etching apparatus for semiconductor devices.

[Conventional technology]

Conventional wet etching! As shown in FIG. 2, a magazine case 3 containing a plurality of semiconductor wafers is immersed in an etching bath 1 containing a chemical solution, and the surface of the semiconductor wafers is etched.

[Problem to be solved by the invention]

In the structure of the conventional etching tank described above, the groove side wall 5 of the magazine case on the surface of the semiconductor wafer is
A or 5b, or air bubbles 6 generated during etching may enter between the semiconductor wafer and the groove side wall of the magazine case, preventing the chemical solution from fully adhering to the semiconductor wafer, resulting in poor product yield due to etching residue. This was causing deterioration and contamination of the next process.

[Means to solve the problem]

The present invention provides a wet etching apparatus for etching the surface of the semiconductor wafer by immersing the semiconductor wafer in an etching tank containing a chemical solution, which includes a rotating body at the bottom of the etching tank that contacts and rotates the semiconductor wafer. It is.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic cross-sectional view for explaining one embodiment of the present invention.

Similar to conventional wet etching equipment, there is an etching tank 1 with a rectangular cross section, and a bottom plate 2 fixed horizontally at a fixed position.
It is composed of A rotating shaft 7 is disposed above the bottom plate 2, penetrating the wall of the etching tank 1, and is connected to a pulse motor (not shown). A plurality of discs 8 are provided on the rotating shaft 7. A magazine case 3 containing semiconductor wafers 4 is immersed in a chemical solution and placed on the bottom plate 2. The orientation flat of the semiconductor wafer 4 is the magazine case 3.
Assume that it is stored so that it is at the bottom of the . Assume that the position of the rotation axis is determined so that the disk contacts the orientation flat of each semiconductor wafer and pushes it up slightly. By rotating the rotary shaft with a pulse motor and swinging the semiconductor wafer, it is possible to prevent air bubbles from entering the groove wall surface of the semiconductor wafer and the magazine case and remaining stationary as in the conventional example.

It is not necessary to mount the disc 8 concentrically with the rotating shaft 7. or,
It may be oval.

〔Effect of the invention〕

As explained above, the present invention has a rotating body attached to the bottom of the etching tank that contacts the semiconductor wafer and gives it a rotational motion, so that the surface of the semiconductor wafer remains in contact with the side wall of the groove of the magazine case, and the etching process is prevented. Since the air bubbles generated inside do not get stuck between the two and become stationary, they do not interfere with etching and eliminate etching residue.
This has the effect of improving yield.

[Brief explanation of drawings]

FIG. 1 is a schematic cross-sectional view showing an etching apparatus of the present invention, FIG. 2(a) is a schematic cross-sectional view showing a conventional etching apparatus,
FIG. 2(b) is a schematic diagram showing an enlarged view of section A in FIG. 2(a). DESCRIPTION OF SYMBOLS 1... Etching tank, 2... Bottom plate in the etching tank, 3... Magazine case, 4... Semiconductor wafer,
5a, 5b... Groove side wall of magazine case, 6... Air bubble, 7... Rotating shaft, 8... Disc.

Claims (1)

[Claims] A wet etching apparatus for etching the surface of the semiconductor wafer by immersing the semiconductor wafer in an etching tank containing a chemical solution, characterized in that the etching tank has a rotating body that contacts and rotates the semiconductor wafer at the bottom of the etching tank. Etching equipment.