Degradation Analysis of InGaN Laser Diodes

Abstract

The current status of InGaN-MQW-laser diodes developed at Osram OS is presented. These lasers are grown on n-conducting SiC, enabling a vertical current path, cleaved facets and excellent heat spreading. The temperature rise during cw operation is measured for different mountings. A p-side up mounted diode with thermal resistance of 18 K/W showed 143 h of cw lasing at 1 mW optical power (T = 25 °C). DC and pulsed aging shows current as main degradation reason compared to heat for InGaN-LDs. Photoluminescence spectra of the quantum wells are being compared before and after degradation caused by current.