[14p-503-1~8] Materials Science and Advanced Electronics Created by Singularity of Nitride Semiconductors

[14p-503-7] A Novel Method to Measure Absolute Internal Quantum Efficiency in III-nitride Semiconductors by Simultaneous Photo-acoustic and Photoluminescence Spectroscopy

〇Atsushi A. Yamaguchi¹, Takashi Nakano¹, Shigeta Sakai¹, Yuya Kanitani², Shigetaka Tomiya² (1.Kanazawa Inst. Tech., 2.Sony Corp.)

Keywords:III-nitride semiconducitor, Internal Quantum Efficiency, Photo-acoustic Measurement

Internal quantum efficiency (IQE) in compound semiconductors is usually estimated from temperature dependence of photoluminescence (PL) intensity by assuming that the IQE at cryogenic temperature is unity. III-Nitride semiconductors, however, usually have large defect-density, and the assumption is not necessarily valid. In this study, we propose a novel method to measure accurate absolute IQE values by simultaneous photo-acoustic (PA) and PL spectroscopy in III-nitride semiconductors, and we have demonstratively performed the measurement for a blue-emitting InGaN quantum-well (QW) sample. The measured IQE values have been compared with the values estimated by the conventional method, and it is shown that the conventional method cannot necessarily give accurate IQE values, and that the proposed method is a promising way to estimate accurate IQE values.