Dry cleaningprocess of crystalline silicon surface in a-Si:H/c-Si heterojunction for photovoltaic applications

摘要

In this work we showed a comparison of the effect of H_2, CF_4/O_2, RF dry etching on the properties of the heterostructure device useful for photovoltaic application. To this aim we performed low temperature (50-300 K) capacitance measurements in a wide range of probe signal frequencies (10 Hz-10 kHz). Differences in the capacitance profile between samples with various plasma dry treatments indicated different defect density profile at interface. With the aid of a finite difference model of the capacitance as a function of temperature and frequency we extracted information about the defect distribution at interface, that greatly influence the photovoltaic properties of the devices.