Straightforward electrical measurement of forward-voltage to investigate thermal effects in InGaN/GaN high-brightness light-emitting diodes

Abstract

Nonradiative recombination mechanisms in InGaN/GaN-based light-emitting diodes investigated by temperaturedependent measurements Appl. Phys. Lett.Investigation of the electroluminescence spectrum shift of InGaN/GaN multiple quantum well light-emitting diodes under direct and pulsed currentsThe junction temperature of InGaN/GaN MQW high-brightness light-emitting diodes is measured using an electrical method based on the dependence of diode forward voltage, V f , on the junction temperature T j . Electroluminescence (EL) data collected during this measurement are presented and used to compare the efficacy of this method for measuring T j to the electrical technique. In devices based on polar III-nitride materials, the temperature dependence of the EL peak energy is obscured by carrier screening and bandfilling; the contributions of these effects are explored and presented. Additionally, the experimental method presented offers an application for extrapolating a thermal relaxation time during the junction temperature measurement. The results from this thermal time constant study are presented and discussed.