Temperature and injection current dependent electroluminescence for evaluation of single-junction single-segment GaAs laser power converter

The spatial electroluminescence intensity and spectral measurements of photovoltaic devices under forward bias have proved to be fast and reliable characterization tools. They enable quick evaluation of material and manufacturing quality and provide information linked to local performance of photovoltaic devices in different operating conditions. In this work, EL images of single-junction single-segment GaAs laser power converters (LPC) and their emission spectra depending on the injection current and LPC temperature are presented and analyzed. A shift of the EL emission peak to smaller energies and a decrease in EL intensity with increasing temperature are observed in spectrally resolved EL measurements. Negative temperature coefficients dEL/dT of EL intensity depending on the injection current are extracted from spatially resolved EL measurements. EL images of the LPCs under low and high injection currents are presented and evaluated.