Influence of face-down and face-up bonding on the degree of polarization of superluminescent diode

Abstract

Face-down and face-up bonded polarization-insensitive buried heterojunction superluminescent diode has been studied in terms of thermal behavior and degree of polarization. Our studies have shown that the thermal rollover of current–power characteristic for face-down bonding was about 1.16 times higher than face-up configurations, and face-down bonding can offer higher heat transfer than face-up one. However, face-down bonding will cause more physical stress to the device, and the average value of degree of polarization for face-down bonding devices (35.3%) was much higher than face-up ones (−2.1%). After 48 h high temperature storage at 85[Formula: see text]C, the stress of face-down devices obtained a better relaxation due to the more stress accumulation.