Investigations of electron spin resonance on light emitting nano-crystallites embedded in a-Si:H films

We report here the studies of electron spin resonance (ESR) on light emitting nano-crystallites embedded in a-Si:H matrix, which are prepared by plasma enhanced CVD on quartz substrates without any post-processing. The ESR spectra contains three components: (1) A pair of hyperfine lines of axial symmetry with g=1.9967 and g⊥=2.0016, and thehyperfine constant 120G; (2) an isotropic line with g=2.0052 and line-width ΔHpp=10G; (3) an axial symmetric line with g=2.0042 and g⊥=2.0057. The dependence of these paramagnetic defects on sample preparation conditions and light emission intensity are presented.