Comparison between structural properties of bulk GaN grown under high N pressure and GaN grown by other methods
In this paper defects formed in GaN grown by different methods are reviewed. Formation of particular defects are often related to the crystallographic direction in which the crystals grow. For bulk crystals the highest growth rates are observed for directions perpendicular to the c-axis. Threading dislocations and nanopipes along the c-axis are not formed in these crystals, but polarity of the growth direction plays a role concerning defects that are formed and surface roughness. For growth of homoepitaxial layers, where growth is forced to take place in the c-direction threading dislocations are formed and their density is related to the purity of constituents used for growth and to substrate surface inhomogeneities. In heteroepitaxial layers two other factors: lattice mismatch and thermal expansion mismatch are related to the formation of dislocations. Doping of crystals can also lead to formation of defects characteristic for a specific dopant. This type of defects tends to be growth method independent but can depend on growth polarity.
- Research Organization:
- Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
- Sponsoring Organization:
- USDOE Director, Office of Science. Office of Basic Energy Studies. Materials Science and Engineering Division (US)
- DOE Contract Number:
- AC03-76SF00098
- OSTI ID:
- 803856
- Report Number(s):
- LBNL-51219; R&D Project: 513340; B& R KC0201030; TRN: US200301%%544
- Resource Relation:
- Conference: ONR Workshop on the Growth of Bulk GaN, Manaus (BR), 05/19/2002--05/23/2002; Other Information: PBD: 31 Jul 2002
- Country of Publication:
- United States
- Language:
- English
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