Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5352117 | Applied Surface Science | 2013 | 6 Pages |
Abstract
This study demonstrates improvement of crystal quality of GaN film by growing it on a micro-faceted GaN template fabricated by in situ etching with an HCl/N2 etching gas mixture at 1050 °C in hydride vapor phase epitaxy (HVPE) reactor. Cathodoluminescence images of the cross-sectional structure showed that there were six sublays in the GaN film grown with in situ etching for five times. Etch pit density (EPD) and high-resolution X-ray diffraction (HR-XRD) measurements showed that the crystal quality of GaN thick film grown on micro-faceted GaN template was better than that of the as-grown GaN. A large number of columnar structures were formed on the micro-faceted GaN template at the initial stage of regrowth process, the coalescence of which played an important role in the reduction of threading dislocation density during the GaN growth. A model has been developed to explain the mechanism of forming process of the columnar structures.
Related Topics
Physical Sciences and Engineering
Chemistry
Physical and Theoretical Chemistry
Authors
Weike Luo, Liang Li, Zhonghui Li, Xiaojun Xu, Jiejun Wu, Xiangshun Liu, Guoyi Zhang,