Optical properties of InAlGaN thin films

• Main Author: 陽士宏
• Other Authors: Kwong-Kau Tiong
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/92501163491431539457

碩士 === 國立臺灣海洋大學 === 電機工程學系 === 98 === We study the optical and electric properties of InxAlyGa1-x-yN epilayers with x ranging from 0.014~0.028 and y ranging from 0.079~0.140 by Photoluminescence (PL) with temperature dependence and optical quenching (OQ) photoconductivity (PC) measurement. The InxAlyGa1-x-yN samples with various In and Al contents were deposited on a sapphire substrate with a GaN buffer layer by low pressure metal organic chemical vapor deposition (MOCVD). The temperature dependent PL of the InxAlyGa1-x-yN epilayers shows a classical “S-shape” behavior. This behavior is attributed to exciton localization due to compositional fluctuations in the InxAlyGa1-x-yN layers. Two broad quenched bands observed at 1.127 eV~1.458 eV and 1.653 eV~1.907 eV are attributed to the existence of the trap level in the InxAlyGa1-x-yN epilayer. The origin of the defects responsible for the optical quenching can be attributed to nitrogen antisite or gallium vacancy.