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Real-Time Optical Monitoring of Flow Kinetics and Gas Phase Reactions Under High-Pressure OMCVD ConditionsThis contribution addresses the real-time optical characterization of gas flow and gas phase reactions as they play a crucial role for chemical vapor phase depositions utilizing elevated and high pressure chemical vapor deposition (HPCVD) conditions. The objectives of these experiments are to validate on the basis of results on real-time optical diagnostics process models simulation codes, and provide input parameter sets needed for analysis and control of chemical vapor deposition at elevated pressures. Access to microgravity is required to retain high pressure conditions of laminar flow, which is essential for successful acquisition and interpretation of the optical data. In this contribution, we describe the design and construction of the HPCVD system, which include access ports for various optical methods of real-time process monitoring and to analyze the initial stages of heteroepitaxy and steady-state growth in the different pressure ranges. To analyze the onset of turbulence, provisions are made for implementation of experimental methods for in-situ characterization of the nature of flow. This knowledge will be the basis for the design definition of experiments under microgravity, where gas flow conditions, gas phase and surface chemistry, might be analyzed by remote controlled real-time diagnostics tools, developed in this research project.
Document ID
20010057234
Acquisition Source
Marshall Space Flight Center
Document Type
Conference Paper
Authors
Dietz, N.
(North Carolina State Univ. Raleigh, NC United States)
McCall, S.
(North Carolina State Univ. Raleigh, NC United States)
Bachmann, K. J.
(North Carolina State Univ. Raleigh, NC United States)
Date Acquired
August 20, 2013
Publication Date
March 1, 2001
Publication Information
Publication: Microgravity Materials Science Conference 2000
Volume: 1
Subject Category
Fluid Mechanics And Thermodynamics
Funding Number(s)
CONTRACT_GRANT: NAG8-1686
CONTRACT_GRANT: NCC8-95
CONTRACT_GRANT: F49620-95-1-0447
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
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