標題: | Effect of Thermal Annealing on a-plane GaN Grown on r-plane Sapphire |
作者: | Ko, Tsung-Shine Lu, Tien-Chang Chen, Jung-Ron Ou, Sin-Liang Chang, Chia-Ming Kuo, Hau-Chung Lin, Der-Yuh 光電工程學系 Department of Photonics |
關鍵字: | non-polar;GaN;annealing;threading dislocation;stack fault |
公開日期: | 2014 |
摘要: | The crystal quality improvement of a-plane GaN grown on r-plane sapphire was demonstrated by applying thermal annealing on as-grown samples in nitrogen ambient. The root mean square roughness of the 1000 degrees C-annealed a-plane GaN was only 0.4 nm measured by atomic force microscopy. Transmission electron microscopy results further indicate threading dislocations were decreased from 5x10(10) cm(-2) to 1.5x10(10) cm(-2) along [0001] GaN and stacking faults were decreased from 8.7x 10(5) cm(-1) to 4.8x 10(5) cm(-1) after the sample was annealed at 1000 degrees C. Room temperature photo luminescence measurements showed band edge emission intensity was enhanced up to 2.6 folds compared to the regular a-plane GaN film. Furthermore, corresponding cathode luminescence images reveal larger emission area for a-plane GaN with annealing than those without annealing, which was attributed to reduction of the nonradiative recombination centers. A series of experiments confirm this annealing process could be useful for further applications of GaN-based optoelectric devices. |
URI: | http://hdl.handle.net/11536/136238 |
ISBN: | 978-1-4799-5038-6 |
ISSN: | 2159-3523 |
期刊: | 2014 IEEE INTERNATIONAL NANOELECTRONICS CONFERENCE (INEC) |
顯示於類別: | 會議論文 |