title: Progress in optimization of transition metal cation chromatography and its application to analysis of silicon wafer contamination.
abstract: Methods are reported which yield sensitive semi-quantitative analysis of transition metal contaminants on silicon wafers. An effective extracting solution is proposed together with compatible concentrators and two eluent (column and post-column) chemistry combinations to measure ppt (10(12)) concentrations and surface densities extending into the 10(10) atoms per cm2 range. Possible applications include numerous steps in wafer and integrated circuit manufacture as well as other solid-surface analysis.
authors.affiliation: MEMC Electronic Materials Co., St. Peters, MO 63376.
authors.forename: K A
authors.initials: KA
authors.lastname: Ruth
authors.forename: R W
authors.initials: RW
authors.lastname: Shaw
mesh_terms: D002412:Cations; D002852:Chromatography, Ion Exchange / Q000379:methods* / Q000592:standards; D012825:Silicon / Q000032:analysis*
chemical_list: D002412:Cations; D012825:Silicon