Anisotropy in the transport of microcrystalline silicon

We have measured the transport properties of several microcrystalline silic on films prepared by hot-wire chemical vapour deposition (HWCVD). The photo current measurements indicate an anisotropy in the optoelectronic propertie s of the material. We have investigated the defect structure in the samples by modulated and transient photocurrent, constant photocurrent method, and capacitance spectroscopy. The results indicate spatial inhomogeneities in the distribution of defects. A likely distribution of defects is proposed w hich can consistently explain the results from the different measurements, (C) 2000 Published by Elsevier Science B.V. All rights reserved.