Deuteron and proton magnetic resonance in amorphous silicon

Deuteron and proton NMR measurements have been made on a series of plasma-deposited a-Si:D,H samples. DMR line shapes show three components: a resolved quadrupolar doublet associated with D bonded to Si well removed from microvoids, a wide quadrupole-broadened central line associated with D located near to and on the surfaces of microvoids, and a sharp temperature-dependent feature associated with molecular ${\mathrm{D}}_2$ in the larger voids. Dipolar $T_2$ decays show two components for both protons and deuterons. There is no strong correspondence between the dipolar broad and narrow lines and the two quadrupolar resonance components observed for bonded D. $T_1$(H) and $T_1$(D) show components associated with spin diffusion to effectively dilute ${\mathrm{H}}_2$ and ${\mathrm{D}}_2$ relaxation centers located in microvoids. ${\mathrm{SiD}}_4$ and ${\mathrm{SiH}}_4$ starting gases produce similar amounts of ${\mathrm{D}}_2$ and ${\mathrm{H}}_2$ under comparable deposition conditions. Two samples show a strong apparently electronic carrier-related nuclear-spin-lattice relaxation contribution near room temperature.