Optical properties of (1-101) InGaN/GaN MQW stripe laser structure on Si substrate

A smooth laser structure on (1-101) GaN microstripes was successfully fabricated on a patterned (100) 8°-off Si substrate. The sample has a high internal quantum efficiency (IQE) compared with blue LEDs on a sapphire substrate. The high-density excitation PL spectrum observed from the cross section of the sample shows marked narrowing, and the integral PL intensity also shows a steep increase. These results indicate the onset of stimulated emission from an InGaN-based multi quantum well (MQW) active layer on (1-101) GaN / (100) Si. To the best of our knowledge, this is the first report of the observation of a stimulated emission from a (1-101) MQW on a Si substrate. We succeeded in fabricating and verifying the high-quality laser structure on semipolar (1-101) GaN on a Si substrate.