The effects of pre-annealing on oxygen precipitation in silicon P/P-epitaxial wafers

Abstract

Abstract Herein, the effect of pre-annealing on oxygen precipitation in a silicon P/P-epitaxial wafer was investigated using an experimental approach. Czochralski-grown silicon wafers were annealed at 800–900 °C to enhance their bulk micro defects (BMDs), before the epitaxial growth process. The effect of the pre-annealing temperature on oxygen precipitation was greater than that of the pre-annealing time, and the effect of pre-annealing temperature varied between polished and epitaxial wafers. Regarding pre-annealed epitaxial wafers that were annealed at low temperatures, the pre-annealing time also had as large an effect on BMD formation as the pre-annealing temperature. These experimental results were used to determine the optimal pre-annealing temperature for enhancing oxygen precipitation in epitaxial wafers. The experimental results regarding the optimal conditions were consistent with prior hypotheses. Crystal originated particles (COPs) and COP-free crystals exhibited their highest BMD density values at similar pre-annealing temperatures.