A Novel Method to Measure Absolute Internal Quantum Efficiency in III-Nitride Semiconductors by Simultaneous Photo-Acoustic and Photoluminescence Spectroscopy

Atsushi A. YAMAGUCHI  Kohei KAWAKAMI  Naoto SHIMIZU  Yuchi TAKAHASHI  Genki KOBAYASHI  Takashi NAKANO  Shigeta SAKAI  Yuya KANITANI  Shigetaka TOMIYA  

Publication
IEICE TRANSACTIONS on Electronics   Vol.E101-C   No.7   pp.527-531
Publication Date: 2018/07/01
Online ISSN: 1745-1353
DOI: 10.1587/transele.E101.C.527
Type of Manuscript: INVITED PAPER (Special Section on Distinguished Papers in Photonics)
Category: 
Keyword: 
internal quantum efficiency,  recombination,  PAS,  PL,  

Full Text: FreePDF(538.7KB)


Summary: 
Internal quantum efficiency (IQE) is usually estimated from temperature dependence of photoluminescence (PL) intensity by assuming that the IQE at cryogenic temperature is unity. III-nitride samples, however, usually have large defect density, and the assumption is not necessarily valid. In 2016, we proposed a new method to estimate accurate IQE values by simultaneous PL and photo-acoustic (PA) measurements, and demonstratively evaluated the IQE values for various GaN samples. In this study, we have applied the method to InGaN quantum-well active layers and have estimated the IQE values and their excitation carrier-density dependence in the layers.