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Real-Time Optical Monitoring and Simulations of Gas Phase Kinetics in InN Vapor Phase Epitaxy at High PressureUnderstanding the kinetics of nucleation and coalescence of heteroepitaxial thin films is a crucial step in controlling a chemical vapor deposition process, since it defines the perfection of the heteroepitaxial film both in terms of extended defect formation and chemical integrity of the interface. The initial nucleation process also defines the film quality during the later stages of film growth. The growth of emerging new materials heterostructures such as InN or In-rich Ga(x)In(1-x)N require deposition methods operating at higher vapor densities due to the high thermal decomposition pressure in these materials. High nitrogen pressure has been demonstrated to suppress thermal decomposition of InN, but has not been applied yet in chemical vapor deposition or etching experiments. Because of the difficulty with maintaining stochiometry at elevated temperature, current knowledge regarding thermodynamic data for InN, e.g., its melting point, temperature-dependent heat capacity, heat and entropy of formation are known with far less accuracy than for InP, InAs and InSb. Also, no information exists regarding the partial pressures of nitrogen and phosphorus along the liquidus surfaces of mixed-anion alloys of InN, of which the InN(x)P(1-x) system is the most interesting option. A miscibility gap is expected for InN(x)P(1-x) pseudobinary solidus compositions, but its extent is not established at this point by experimental studies under near equilibrium conditions. The extension of chemical vapor deposition to elevated pressure is also necessary for retaining stoichiometric single phase surface composition for materials that are characterized by large thermal decomposition pressures at optimum processing temperatures.
Document ID
20030060500
Acquisition Source
Marshall Space Flight Center
Document Type
Conference Paper
Authors
Dietz, Nikolaus
(Georgia State Univ. Atlanta, GA, United States)
Woods, Vincent
(Georgia State Univ. Atlanta, GA, United States)
McCall, Sonya D.
(Spelman Coll. Atlanta, GA, United States)
Bachmann, Klaus J.
(North Carolina State Univ. Raleigh, NC, United States)
Date Acquired
September 7, 2013
Publication Date
February 1, 2003
Publication Information
Publication: 2002 Microgravity Materials Science Conference
Subject Category
Solid-State Physics
Funding Number(s)
CONTRACT_GRANT: NAG8-1686
CONTRACT_GRANT: NCC8-95
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
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