ESR and transport in microcrystalline silicon

We report on the electron spin resonance and electrically detected magnetic resonance and conductivity of mu c-Si thin films. We have systematically changed the defect density, N(D), by thermally annealing the samples and found that transport is not controlled by defects if N(D) < 10(18)cm(-3). For N(D) > 10(18)cm(-3), a decrease of conductivity by almost five orders of magnitude is found and an electrically detected magnetic resonance enhancing signal appears in the dark current. The results will be discussed in terms of a simple model for barrier-limited transport assuming that all defects are located either at the boundaries of the crystallites or at the boundaries of the columns. (C) 1998 Elsevier Science B.V. All rights reserved.