Investigation on ESD-stressed GaN/InGaN-on-sapphire blue LEDs

After the results of a previous work [1], intermediate robustness of GaN/In GaN-on sapphire blue LEDs vs. ESD stress is investigated. Different from ot her cases, no evidence for defect-related weakness is available. The role o f resistive current paths in focusing the flow of charge and the voltage pe aks under both de and transient conditions is then considered, by means of simple considerations on a distributed network of elementary diodes and res istors representing the main electrical features of the LED structure. EL a nd EBIC maps on both regular and failed devices support the proposed interp retation. (C) 2001 Published by Elsevier Science Ltd.