Defects in hydrogenated microcrystalline silicon (μc‐Si:H) prepared by plasma-enhanced chemical vapour deposition at 100C were investigated as a function of crystalline volume fraction (Xc) from electron spin resonance measurements. Magnetic centers responsible for electron spin resonance were suggested from g-value considerations to be dangling bonds on the surface of crystalline grains for Xc of less than 50% and positively charged single vacancies with positive correlation energy inside the crystalline grain for Xc of more than 50%. For the latter Xc range, it was suggested from correlation of these defects with photoluminescence and its light-induced effect and optically detected magnetic resonance that they were non-radiative centers. Further, the low-energy photoluminescence associated with the microcrystalline phase in μc‐Si:H was concluded to arise from radiative recombination between trapped electrons in the conduction-band tail and trapped holes in the valence-band tail arising from disordered potentials around the grain boundary.

Defects in Hydrogenated Microcrystalline Silicon Prepared by Plasma-Enhanced Chemical Vapour Deposition. K.Morigaki, C.Niikura, H.Hikita, M.Yamaguchi: Journal of Applied Physics, 2009, 105[8], 083703