High Mobility of Low Temperature GaN Grown by Two Heater MOCVD

• Main Authors: Lin, Chih-Wei, 林智偉
• Other Authors: Chen, Wei-Kuo
• Format: Others
• Language: zh-TW
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/31349271360461005870

碩士 === 國立交通大學 === 電子物理系所 === 103 === In this theses, we use the home-made two heater MOCVD reactor to grow low-growth temperature GaN thin films at 850℃. The electrical and optical properties of the samples were investigated by Hall, Temperature dependent Hall, X-ray diffraction and photoluminescence measurements. Hall measurement results indicate that the optimized ceiling temperature of GaN thin film is 1050℃ in ceiling temperature series. The carrier mobility and carrier concentration of GaN thin film is 515 cm2/Vs and 5.1x1016 cm-3.The X-ray diffraction and temperature dependent Hall measurement are employed to confirm the scattering mechanism. The X-ray diffraction spectra shows that the dislocation density doesn't change with the various ceiling temperature, implying that the dislocation density won't affect by ceiling temperature and improve thin film quality. The temperature dependent Hall measurement indicates carrier mobility is linear relationship with T3/2 in low temperature measurement region and linear relationship with T-1/2 in high temperature measurement region, and we speculate that the native defects scattering dominate the carrier mobility.