Exploratory observations of effect of rapid thermal processing on silicon minority carrier lifetime using laser microwave photoconductance method

Abstract

The effect on the minority carrier lifetime of Czochralski wafers undergoing rapid thermal processing is being examined. It was found that the minority carrier lifetime of silicon increased significantly after the rapid thermal process was completed. It was also discovered that the lifetime took more than 200 h to reach a steady-state value after the rapid thermal process. Once this value had been reached, it remained fairly stable even at elevated (150°C) temperature. Oxygen annihilation of Czochralski wafer and modification of the Si-SiO2 interface by RTP are suggested as possible explanations for the observation.