REMOVAL OF METAL AND ORGANIC CONTAMINANTS FROM SILICON SUBSTRATES USING ELECTROLYSIS-IONIZED WATER CONTAINING AMMONIUM-CHLORIDE

The efficiency of removing metal and organic contaminants from silicon substrate surfaces by using electrolysis-ionized water containing amm onium chloride was compared with the removal efficiency using an ammon ium hydroxide and hydrogen peroxide mixture and a hydrochloric acid an d hydrogen peroxide mixture. Before and after wet cleaning, metal impu rities were measured using hydrofluoric acid vapor-phase decomposition atomic absorption spectrometry, and the organic impurities were measu red using thermal desorption spectroscopy gas chromatography mass spec trometry. The electrolysis anode water removed both metal and organic contaminants due to its high oxidation-reduction potential and low pH. Oxidation and oxidative degradation are effective for the removal of both metal and organic contaminants from silicon substrate surfaces, a nd metallic complex acids are stable at low pH of the electrolysis ano de water. The electrolysis cathode water, on the other hand, cannot re move metal or organic contaminants because of its high pH and low oxid ation-reduction potential.