Odmr Measurements of Microcrystalline Silicon

Abstract

ABSTRACTUndoped microcrystalline silicon films of high crystalline volume fraction were studied by optically detected magnetic resonance (ODMR). Luminescence energies peak at 0.88 eV and emission at 1.3 eV arising from amorphous tissue is negligible. Recombination involving dangling bonds (g=2.0052, g=2.0043) in disordered regions or crystallites and shallow states near the conduction band (g= 1.998) in the crystalline parts of the material are observed. At temperatures below 30 K a very broad feature of approximately 1000 G width is observed, possibly originating from two separate resonances with high g-values of g=2.1 and g=2.08. We suggest the origin to be of hole-states near or in the valence band. No evidence for excitonic recombination was found. Frequency response indicates ODMR lifetimes of all resonances in the range of 10−5s to 10−4s.