On electronic properties from the application of field dependence SSPG approach to polymorphous and microcrystalline silicon semiconductors

Further information on electronic properties, like trapped carrier density, for hydrogenated microcrystalline and polymorphous silicon thin films prepared by hot-wire chemical vapor deposition (HWCVD) and plasma-enhanced chemical vapor deposition (PECVD) techniques can be deduced from the experimental data of the high electric field dependence of the coefficient β in the steady-state photocarrier grating (SSPG) technique. This is achieved by adopting a convenient theoretical approach of the SSPG problem based on the small-signal photocurrent to fit the experimental data at different grating periods and temperatures. The values of small-signal mobility lifetime product, the drift (diffusion) lengths for holes and electrons can be estimated by exploiting the relations among the transport parameters. The correlation between the photoelectronic properties and the trapped carrier density is also discernable. The trapped carrier density values are also obtained from the adopted approach and compared to corresponding values using other approaches.