The Same Formation Mechanism of Surface Pits for both a- and c-plane GaN
- DOI
- 10.2991/ame-16.2016.161How to use a DOI?
- Keywords
- Screw dislocation, Surface pit, Frank theory,a-plane GaN,c-plane GaN,Island coalescence
- Abstract
Surface pits in a-plane GaN have long been considered as a result of island coalescence in literature, while pits in c-plane GaN are the surface termination of screw dislocations. It is found in the paper that small surface pits on a-plane GaN also terminate perfect screw dislocations and partial dislocations (PD), whichis due to the intrinsic nature of the spiral growth of screw dislocations. This resulthas demonstrated that a-plane GaN also follows the prediction based on Frank's classical theory of dislocated crystals. Moreover, although caused by dislocation, the relative size of the small pits will be affected by the kinetic process of the atomic reactions on the surface through V/III ratio variation. Meanwhile, large hexagonal surface pits are observed on c-plane GaN grown under low V/III ratio, which is formed under the same mechanism as the large triangular or pentagonal pits on a-plane GaN surface. During the island coalescing, the lateral growth of the inclined facets are in competition with the vertical growth in the epitaxial orientation, so incomplete island coalescence will produce large surface pits for both a- and c-plane GaN. Under this mechanism, a triangular pit of a-plane GaN could be transformein to a pentagonal pit upon increasing temperature.
- Copyright
- © 2016, the Authors. Published by Atlantis Press.
- Open Access
- This is an open access article distributed under the CC BY-NC license (http://creativecommons.org/licenses/by-nc/4.0/).
Cite this article
TY - CONF AU - Zhi-Yuan Gao AU - Jiang-Jiang Li AU - Xiao-Wei Xue AU - De-Shu Zou PY - 2016/06 DA - 2016/06 TI - The Same Formation Mechanism of Surface Pits for both a- and c-plane GaN BT - Proceedings of the 2nd Annual International Conference on Advanced Material Engineering (AME 2016) PB - Atlantis Press SP - 991 EP - 1002 SN - 2352-5401 UR - https://doi.org/10.2991/ame-16.2016.161 DO - 10.2991/ame-16.2016.161 ID - Gao2016/06 ER -