FFT Photoimpedance Measurements of Semiconductors for Solar Application

摘要

Based on FFT impedance spectroscopy, a fast technique for characterizing relevant properties of semiconductors for solar cell application has been developed. FFT impedance is a fast and reliable method for linear response measurements of, e.g. various electrochemical reaction systems in a wide frequency range (1) based on current or voltage modulation. In this approach a modulated front side illumination as perturbation was used to measure the frequency dependent photoresponse (2) of photoactive electrochemical half-cells as well as complete solar cells. The possibility of investigating experimental systems that show a (reasonable) parameter drift and to be able to recognize non-linear behavior by analyzing the response spectra makes FFT impedance technique an interesting tool for evaluating "solar" materials.