Wafer cleaning method and wafer cleaning equipment

Abstract

The invention provides a wafer cleaning method and wafer cleaning device. The wafer cleaning method comprises the steps that supercritical fluid of carbon dioxide and aerosol of carbon dioxide are used for flushing the surface of a wafer at the same time, and then the carbon dioxide on the surface of the wafer is volatilized into a gaseous state; and organic matters and particulate pollutants are separated from the surface of the wafer in the flushing process, so that the organic matters and the particulate pollutants on the surface of the wafer are cleaned. The physical property that CO2 can be converted in different forms of supercritical fluid, liquid, gas and aerosol through pressure or temperature changes is utilized, CO2 is introduced into the wafer cleaning process to replace traditional RCA cleaning agents SC1 and SPM to remove particles and organic matter, and the limitation that a traditional cleaning method is large in ultra-pure water use amount, large in chemical pollution amount, large in waste amount and low in efficiency is broken through.

Description

technical field [0001] The invention relates to the field of wafer cleaning, in particular to a wafer cleaning method and wafer cleaning equipment. Background technique [0002] The cleaning of the wafer surface in the semiconductor industry mainly uses various physical and chemical methods to remove particle pollutants, organic pollutants and metal pollutants on the wafer surface, so that its cleanliness meets the material processing standards. Among them, the chemical method is mainly RCA wet cleaning method, [0003] The RCA wet cleaning method mainly includes the following cleaning solutions. [0004] (1) SPM: H 2 SO 4 / H 2 o 2 120~150℃. SPM has high oxidation ability, can dissolve metals in cleaning solution after oxidation, and can oxidize organic matter to generate CO 2 and H 2 O. Cleaning silicon wafers with SPM can remove heavy organic contamination and some metals on the surface of silicon wafers, but when the organic contamination is particularly seriou...

AI Technical Summary

Problems solved by technology

The cleaning brush needs to use special materials to avoid being corroded by acid and alkali. At the same time, long-term use of the brush head itself will accumulate pollutants and contaminate the wafer

The tedious and complicated cleaning process is closely linked and interlocking. Each cleaning process needs to be strictly controlled to avoid wasting the entire cleaning cost. In severe cases, the entire wafer will be scrapped

[0009] However, the existing cleaning process consumes a lot of chemical reagents and ultrapure water, which requires high acid and alkali corrosion resistance of equipment; and the cleaning steps are complicated, which may lead to the introduction of new impurities

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