Characterization of AlxGa1-xN Epilayers and AlGaN/GaN 2DEG Heterostructures Grown by Molecular Beam Epitaxy

• Main Authors: Chang, Yu-Wei, 張祐維
• Other Authors: Chou, Wu-Ching
• Format: Others
• Language: en_US
• Published: 2018
• Online Access: http://ndltd.ncl.edu.tw/handle/79gfsv

碩士 === 國立交通大學 === 電子物理系所 === 106 === A high crystal quality GaN channel layer, a series of 0% to 100% AlxGa1-xN ternary alloy, and AlGaN/GaN two-dimensional electron gas (2DEG) heterostructures have been grown by plasma-assisted molecular beam epitaxy (PA-MBE) on MOCVD-grown semi-insulating GaN templates. A wide range of measurements were conducted on the GaN channel layer samples, AlxGa1-xN samples, and 2DEG samples to study the interplay between their characteristics. A high sheet carrier concentration of 1.42×1013 cm-2 and a low sheet resistance of 599 Ω / sq were achieved by performing different treatments at the AlGaN/GaN heterointerface. However, the mobility of the 2DEG was rather low and the values were scattered from sample to sample, presumably due to the unoptimized GaN surface morphology and Al content fluctuation in the AlGaN barrier layer.