Doping and temperature dependence of paramagnetic states in microcrystalline silicon

Abstract

Continuous wave and pulsed electron spin resonance (ESR) in the dark and under light illumination are used to study the doping and temperature dependence of defect, conduction electron and dopant states in microcrystalline silicon. Two resonances are found, which are attributed to silicon dangling bond states and located in different structural environments of the material. Light-induced ESR suggests that these two states have different energies, while in dark ESR, both show a wide and flat distribution in energy. The intensity of a third resonance from conduction electrons shows an almost 1:1 correlation with conductivity over three orders of magnitude. All resonances exhibit a Curie-like temperature dependence and the linewidth of the conduction electron resonance increases with temperature due to a decrease in the spin lattice relaxation time. Hyperfine interaction with phosphorus in n-type material and indications of hole states in p-type material are reported.