JPS6024464Y2 - Diffusion impurity source coating equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rotating suction jig for semiconductor wafers in a spin coating apparatus for a diffused impurity source.

2. Description of the Related Art As one method for diffusing impurities into semiconductor wafers, a method is known in which a liquid diffusion impurity source is spin-coated onto a semiconductor wafer and then heat treatment is performed.

At this time, the semiconductor wafer coated with the diffused impurity source is heat treated without going through a cleaning process, but during this cleaning process, the impurity source coated is eluted into the cleaning solution, and after the heat treatment, the desired diffused impurity is This is because the concentration cannot be obtained.

In view of the above-mentioned circumstances, it is important to avoid contamination of the semiconductor wafer as much as possible, especially contamination with heavy metals, when spin-coating the diffused impurity source.

However, when spin coating a semiconductor wafer with a diffused impurity source, the jig that holds the back side of the semiconductor wafer by suction on the rotating shaft has conventionally been made of metal such as stainless steel, and the above-mentioned heavy metal contamination has not been considered. It wasn't.

For this reason, heavy metals such as iron, nickel, and chromium that make up stainless steel diffuse into the semiconductor wafer from the back surface of the semiconductor wafer, and reach the surface of the semiconductor wafer at a high diffusion rate, causing oxidation-induced stacking faults (O3F: Oxicla).
tion Stacking Fault).

In other words, if there is heavy metal contamination near the surface of a semiconductor wafer, O3F will be produced due to thermal oxidation at a temperature of 1000°C or higher;
6 (Unexamined Japanese Patent Publication No. 53-108373).

When this O3F comes into contact with the PN junction, it causes leakage current and lowers the manufacturing yield.

The present invention is characterized in that quartz glass or resin is used as the material of the above-mentioned semiconductor wafer suction holder to avoid heavy metal contamination.

According to the present invention, the occurrence of crystal defects such as stacking faults due to heavy metal contamination can be reduced, and deterioration of device characteristics can be prevented.

Hereinafter, the present invention will be explained in more detail with reference to the drawings.

FIG. 1 shows an impurity diffusion source coating machine according to an embodiment of the present invention.

An impurity diffusion source dropping nozzle 1, a semiconductor wafer 2 to which the impurity diffusion source is applied, and a suction jig 3 are shown. For example, rotational coating of an antimony diffusion source is performed in such a positional relationship.

In the present invention, the material of the suction jig 3 having the vacuum suction hole 4 for suctioning and adhering the semiconductor wafer 2 is, for example, quartz glass, which is free from heavy metal contamination and has excellent chemical resistance, or fluorine resin, which also has excellent processability. It is characterized by being made of resin such as.

As described above, according to the present invention, since a material free from heavy metal contamination is used, O3F is not generated even during subsequent thermal oxidation, and semiconductor devices can be manufactured with high yield.

In the above embodiments, an antimony diffusion source applicator has been described, but the present invention is also effective for other impurity diffusion sources, such as arsenic, boron, phosphorus, and the like.

Needless to say, it is also effective for photoresistor coating machines and rotary suction jigs for scribing devices.

As explained above, the present invention is effective for avoiding heavy metal contamination of semiconductor wafers by a suction jig during spin coating of an impurity diffusion source.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a main part of an impurity diffusion source coating apparatus in an embodiment of the present invention. 1... Impurity diffusion source dropping nozzle, 2...
・Semiconductor wafer 3...Adsorption jig.

Claims (1)

[Scope of utility model registration request] What is claimed is: 1. An apparatus for spin-coating a diffused impurity source on the surface of a semiconductor wafer, characterized in that a jig that holds and rotates the semiconductor wafer by vacuum suction is made of quartz glass or resin.