A method for measuring the minority carrier lifetime in silicon carbide semiconductor by the injection electroluminescence at point contacts is presented. The principles involved and measuring equipment used are described. Experiments on some important factors, such as resonance disturbance, electrical properties and electroluminescence characteristics of the point contacts, have been performed. Some feasible precautions that must be taken in order to avoid resonance disturbance and contact by-passing and to control rectification ratios are described. It is shown that in order to ensure reliability of experimental results, a knowledge of the electroluminescence characteristics of the samples should be required before measuring. By means of this method, the minority carrier lifetimes for some silicon carbide single crystals have been measured, and for most crystals these values are found to be smaller than 4.2×10-9 sec.
下载:
