INFLUENCE OF ORGANIC IMPURITIES IN HYDROGEN-PEROXIDE FOR ADVANCED WETCHEMICAL-PROCESSING

An improved high purity hydrogen peroxide was developed for advanced s emiconductor devices manufacturing. After treatment of a Si wafer with this hydrogen peroxide, no metallic impurity was adsorbed onto the Si wafer surface. However, a few parts per million of organic impurities remain in the hydrogen peroxide as total organic carbon (TOC). These organic impurities result from the production process f or raw hydroge n peroxide and are identified as formic acid, acetic acid, and cyclohe xanone deviatives. To examine the influence of organic impurities on s emiconductor devices, we evaluated the electrical characteristics of m etal oxide semiconductor (MOS) diodes with thermal oxide films, includ ing chemical oxide by treatment with the improved hydrogen peroxide. I n spite of high organic impurity content, the experimental results sho w that the organic impurities in the hydrogen peroxide did not affect the properties of MOS diodes with about 9 nm oxide films.