Electrical quality of low-temperature (Tdep=775 °C) epitaxial silicon: The effect of deposition rate

The results of an investigation of the effects of varying the deposition rate on the surface morphology and electrical characteristics of low-temperature (Tdep=775 °C) epitaxial silicon are presented. The data indicate that the electrical characteristics are a strong function of the growth rate, even more so than the deposition temperature. Varying the growth rate by a factor of 16 varies the minority-carrier lifetime and reverse-bias diode leakage current by five orders of magnitude, and has a strong impact on the surface morphology of the epitaxial layer. Deposition conditions will be reported that yielded a minority-carrier lifetime of 480 μs, which is the highest lifetime reported in low-temperature epitaxial silicon.