Analysis of Reverse-Biased Electrostatic-Discharge-induced Degradation of GaInAsP/InP Buried Heterostructure Laser Diode

We clarified the mechanism of the degradation of reverse-biased electrostatic discharge (ESD). Although the degradation mechanism of forward-biased ESD has been clarified, that of reverse-biased ESD remains unclear. We prepared a 1.31 mu m GaInAsP/InP distributed feedback laser diode with a conventional pn-InP buried heterostructure for the analysis of the degradation mechanism of reverse-biased ESD. We used two approaches, namely, the failure analysis and numerical analysis of electric field. We found a defect inside an active layer in the early stage of degradation. Interestingly, such a defect was generated at the periphery of an active layer, but not at the center. On the other hand, we found that a high electric field occurs at an active layer under a reverse-biased condition, particularly at the periphery of an active layer. We also demonstrated the improvement in the tolerance to ESD with a decrease in electric field. From these results, we successfully confirmed that reverse-biased-ESD-induced degradation is caused by the concentration of an electric field. (C) 2009 The Japan Society of Applied Physics