Esr-spectrum of amorphous silicon

The ESR-linewidth of a-Si consists of a temperature-independent part ΔH_pp(O) and a temperature-dependent contribution 5Hpp(T), the latter being closely related to the hopping conductivity. δH_pp(O) is to a large part determined by a g-value spectrum as can be concluded from measurements at different magnetic fields H_o. Additionally in some cases exchange interaction is involved. Annealing of glow-discharge a-Si and the influence of hydrogen effusion on the ESR-spectrum is investigated. In the case of boron-doped a-Si a new line with g = 2.0038 can be resolved which is ascribed to a center with a dangling bond on a silicon atom with one Si-H bond.