Accession Number:

ADA256762

Title:

Temperature Dependence of Species Concentrations Near the Substrate during CVD Diamond Growth

Descriptive Note:

Technical rept.

Corporate Author:

CALIFORNIA INST OF TECH PASADENA DIV OF ENGINEERING AND APPLIED SCIENCE

Personal Author(s):

Report Date:

1992-10-01

Pagination or Media Count:

33.0

Abstract:

Measurements have been made of the temperature dependence of CH3, CH4, and C2H2 very near the substrate during filament-assisted diamond growth. CH3 was detected using 21 resonance-enhanced multiphoton ionization REMPI, and CH4 and C2H2 concentrations were measured using sampling mass spectrometry. A strong dependence of the CH3 REMPI signal on substrate temperature was observed, which at low temperatures may be characterized as having an activation energy of approximately 4 - 1 kcalmole. Methane and acetylene, on the other hand, are relatively independent of substrate temperature. These results are most likely due to recombination of methyl to methane in the cool gas layer near the substrate or on the surface at low substrate temperatures.

Subject Categories:

  • Organic Chemistry
  • Physical Chemistry
  • Coatings, Colorants and Finishes
  • Thermodynamics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE