Advanced Search

Browse by Discipline

Scientific Societies

E-print Alerts

Add E-prints

E-print Network

  Advanced Search  

Materials Science and Engineering B 127 (2006) 9197 Short communication

Summary: Materials Science and Engineering B 127 (2006) 9197
Short communication
Oxynitride mediated epitaxy of gallium nitride on silicon(1 1 1) substrates
in a merged hydride/metal-organic vapor phase epitaxy system
M.A. Mastro, O.M. Kryliouk, T.J. Anderson
Department of Chemical Engineering, University of Florida, Gainesville, FL, USA
Received 5 July 2005; received in revised form 29 August 2005; accepted 7 September 2005
A technique was developed to deposit GaN on a Si(1 1 1) substrate by a four-step process in a single reactor: formation of ultra-thin oxide,
conversion to an oxynitride via NH3 exposure at the onset of growth, low-temperature MOCVD of GaN, followed by HVPE of GaN. It was found
that this oxynitride compliant layer served to relieve stress at the GaN/Si interface as well as protect the Si substrate from reaction with free Ga atoms
present during the initial stages of growth and interfacial reactions with the adjoining GaN film. Electron microscopy revealed that an ultra-thin
(less than 2 nm) oxynitride could maintain the hexagonal epitaxial relationship of the Si substrate allowing growth of single crystal GaN. It was
shown experimentally that formation of a thicker oxynitride layer was detrimental to GaN epitaxy due to loss of the epitaxial relationship. In the
final HVPE step, single crystal GaN films were deposited from a traditional growth temperature of 950 down to 560
C which is the lowest reported
temperature for VPE of single crystal GaN. The unique reactor configuration allowed the HVPE process to initiate on a pristine MOCVD GaN
surface. Additionally, epitaxy at low temperature was achievable due to the presence of free HCl which suppresses the formation of energetically
unstable nuclei.
2005 Elsevier B.V. All rights reserved.


Source: Anderson, Timothy J. - Chemical Engineering Department, University of Florida


Collections: Materials Science