TXRF Analysis of SC-1 Treated Silicon Wafers

Silicon wafer cleaning is the most frequently applied processing step in the integrated circuit manufacturing sequence. This process is intended to remove several different types of contaminants, among them particles, metallics, and organics. It has been estimated, however, that over fifty percent of yield losses in integrated circuit manufacturing are caused by contamination remaining on the surface of silicon wafers after cleaning. It is the object of this article to document the effects of using improved, ultrahigh purity chemicals on silicon wafer surfaces as measured by total reflection x-ray fluorescence, TXRF. During this study, silicon samples were cleaned with standard grade chemicals and ultrahigh purity chemicals, and metallic impurities were then measured with TXRF. It was found that the use of ultrahigh purity chemicals substantially reduced the amount of surface contamination present on wafer surfaces after cleaning