Accession Number : AD0480799

Title :   THE CONDENSATION COEFFICIENT OF ALN.

Descriptive Note : Technical rept. 1 Jul 62-31 Aug 65,

Corporate Author : CINCINNATI UNIV OHIO

Personal Author(s) : Hoch ,M. ; Ramakrishnan,D.

Report Date : OCT 1965

Pagination or Media Count : 70

Abstract : The condensation coefficient of AlN was measured by following the rate of exchange is isotopic N2 gas (N15) with AlN14(s) and that of N2 gas (N14) with AlN15(s) using a time-of-flight mass spectrometer. The isotopic N2 gas (N15) was generated by decomposing AlN15(s) in the same Knudsen effusion cell in which the exchange measurements were carried out. Thus, the gas and the substrate were at exactly the same temperature. The condensation coefficient beta is defined as that fraction of gas molecules hitting the surface which undergoes an exchange reaction with the solid. In the temperature range 1800-1900 K, beta = 0.005.

Descriptors :   (*ALUMINUM COMPOUNDS, *NITRIDES), (*CONDENSATION, *NITRIDES), ISOTOPES, GASES, SOLIDS, EXCHANGE REACTIONS, REACTION KINETICS, HIGH TEMPERATURE, MASS SPECTROSCOPY, SURFACES, CONTAMINATION, DIFFUSION, PELLETS, VAPORIZATION, LABORATORY EQUIPMENT, MATHEMATICAL ANALYSIS, SPECTRUM ANALYZERS

Subject Categories : Atomic and Molecular Physics and Spectroscopy

Distribution Statement : APPROVED FOR PUBLIC RELEASE