Author:
Kunst Marinus,Schwarz Reinhard
Abstract
In this work, it will be shown that the change of the microwave reflection of a semiconductor by illumination can be used to determine the photoconductivity. The reliability of the method is successfully tested by monitoring the change of the position of the sample in the microwave field compared to results calculated with a simple model. Besides, the parameters determined by the measurements agree with those for a sample with known parameters (silicon). The use of illumination with fast laser pulses makes contactless study of excess charge carrier kinetics possible. Examples are given for measurements of systems difficult to access with conventional photoconductivity measurements: an amorphous semiconductor, a-Si:H, and a semiconducting powder, TiO2.