Experimental technique to correlate optical excitation intensities with electrical excitation intensities for semiconductor optoelectronic device characterization

摘要

We discuss a proposed experimental technique for correlating optical excitation intensities in photoluminescence measurements with electrical excitation intensities in electroluminescence measurements for optoelectronic device characterization purposes. The technique utilizes the reverse saturation current under optical excitation as a measure of the optical excitation intensities and translates it to electrical excitation intensities as the forward current of the same amount. InGaN-based blue and green light-emitting diodes were examined to demonstrate the validity of the proposed technique. 4 W cm~(-2) of optical excitation intensity was determined to be approximately the same as a sub-mA forward current under the present experimental conditions. Photoluminescence and electroluminescence characteristics were compared by applying the determined excitation intensity; spatial uniformity of luminescence was found to differ from each other in green-emitting devices.