Structural TEM study of nonpolar a-plane gallium nitride grown on(112_0) 4H-SiC by organometallic vapor phase epitaxy
Conventional and high resolution electron microscopy havebeen applied for studying lattice defects in nonpolar a-plane GaN grownon a 4H-SiC substrate with an AlN buffer layer. Samples in plan-view andcross-section configurations have been investigated. Basal and prismaticstacking faults together with Frank and Shockley partial dislocationswere found to be the main defects in the GaN layers. High resolutionelectron microscopy in combination with image simulation supported Drum smodel for the prismatic stacking faults. The density of basal stackingfaults was measured to be ~;1.6_106cm-1. The densities of partialdislocations terminating I1 and I2 types of intrinsic basal stackingfaults were ~;4.0_1010cm-2 and ~;0.4_1010cm-2, respectively. The energyof the I2 stacking fault in GaN was estimated to be (40+-4) erg/cm2 basedon the separation of Shockley partial dislocations. To the best of ourknowledge, the theoretically predicted I3 basal stacking fault in GaN wasobserved experimentally for the first time.
- Research Organization:
- Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
- Sponsoring Organization:
- USDOE; Department of Defense. Air Force Office of ScientificResearch OGMORD 52K44134
- DOE Contract Number:
- DE-AC02-05CH11231
- OSTI ID:
- 860233
- Report Number(s):
- LBNL-58933; R&D Project: M50017; BnR: 400403109
- Journal Information:
- Physical Review B, Vol. 71; Related Information: Journal Publication Date: 2005
- Country of Publication:
- United States
- Language:
- English
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