Growth of GaN boules via vertical HVPE
- 作者：E. Richter ; eberhard.richter@fbh-berlin.de ; M. Grü ; nder ; C. Netzel ; M. Weyers ; G. Trä ; nkle
- 关键词：A1. Substrates ; A2. Single crystal growth ; A3. Hydride vapor phase epitaxy ; B1. GaN
- 刊名：Journal of Crystal Growth
- 出版年：2012
- 期刊代码：49_00220248
- 类别：ch
- 出版时间：1 July, 2012
- 卷：350
- 期：1
- 页码：89-92
- 文件大小：412 K
摘要
GaN boules were grown up to thicknesses of 6.3 mm via vertical HVPE on 2 in. GaN/sapphire templates. The usable boule length is limited by surface defects. Two different sub-surface disturbances were identified to be responsible for these surface defects using optical inspection and low-temperature photoluminescence on polished m-plane slices cut from the boules. One disturbance starts already at the interface to the used template resulting in large V-pits at the surface. The other one occurs after undisturbed GaN growth of several mm and leads to local cracking networks and small V-pits at the surface. Both lead to deteriorated structural properties of subsequently grown material with red-shifted and broadened exciton emission. In contrast, the undisturbed material having a smooth surface is of high material quality and shows constant energies of the exciton emissions with narrow line widths.