APPLICATION AND COMPARISON OF SPV AND μPCD FOR IRON MEASUREMENT IN SILICON WAFER MANUFACTURING

摘要

Minority carrier lifetime tools μ-PCD and SPV diffusion length are used in process monitoring in silicon wafer manufacturing for metal contamination control. In p-type silicon, both lifetime tools had been correlated with DLTS so as to be able to measure [Fe] concentration. In comparison of these two methods, a good correlation was obtained in a large range with extrapolation to the upper le10/cm~3 level using Czochralski (CZ) silicon samples. In general, SPV resulted in a higher [Fe] than μ-PCD methods. At lower le10/cm~3 level, the boron and oxygen concentrations significantly limit the [Fe] detection capability of μ-PCD, but less significantly on that of SPV.