Contribution of ICP-IDMS to the certification of antimony implanted in a silicon wafer - comparison with RBS and INAA results

A thin-layer reference material for surface and near-surface analytical met hods was produced and certified. The surface density of the implanted Sb la yer was determined by Rutherford backscattering spectrometry (RBS), instrum ental neutron activation analysis (INAA), and inductively coupled plasma is otope dilution mass spectrometry (ICP-IDMS) equipped with a multi-collector . The isotopic abundances of Sb (Sb-121 and Sb-123) were determined by mult i-collector ICP-MS and INAA. ICP-IDMS measurements are discussed in detail in this paper. All methods produced values traceable to the Sl and are acco mpanied by a complete uncertainty budget. The homogeneity of the material w as measured with RBS. From these measurements the standard uncertainty due to possible inhomogeneities was estimated to be less than 0.78% for fractio ns of the area increments down to 0.75 mm(2) in size. Excellent agreement b etween the results of the three different methods was found. For the surfac e density of implanted Sb atoms the unweighted mean value of the means of f our data sets is 4.81x10(16) cm(-2) with an expanded uncertainty (coverage factor k=2) of 0.09x10(16) cm(-2). For the isotope amount ratio R (Sb-121/S b-123) the unweighted mean value of the means of two data sets is 1.435 wit h an expanded uncertainty (coverage factor k=2) of 0.006.