Observation of unequal densities for sulfur defects in silicon predeposited by low fluence ion implantation*

Abstract

The dynathermal current and capacitance responses of two isotopes of sulfur, 32s and 34s predeposited by low fluence ion implantation into siliconp +- n junction diodes are presented. As opposed to all previous studies, in this work unequal densities are seen for the shallow and deep sulfur defects, for both the 32s− and 34− related defects. Additionally, the dynathermal response of the deep 34s center is seen to exhibit a shift of 3 K from that of 32S at a fixed heating rate of 9.5 ±0.1 K/s, consistent with the isotope dependence of the thermal emission process observed earlier for these cen-ters by isothermal capacitance measurements.