Quantitative Analysis using SIMS Primar Area of Instrumental Ion current analvSIs transmission factor for a+ densi IA+=jxA×YA+xfA+×CA+1 Measured secondary Secondary ion yield Atomic concentration of a on current of a+ in the matrix T in the matrix T in the matrix T L T=S,T A+×CA+ A+ Sensitivity factor for A in the matrix T Very difficult to calculate SA+T. It depends on the 1. Element and matrix 2. SIMS instrument 3. System parameters Standards are normally used Ire Standard Use s,I from standard Sample Measure IA+T the same matrix From known CAT Find CT Find, T