EVALUATION OF VAPOR DEPOSITION GROWTH OF OXIDE SINGLE CRYSTALS FROM METAL HALIDES
Abstract
Preliminary investigations to determine significant vapor growth parameters were completed. Growth rate, substrate orientation and temperature, reactant vapor velocity, total pressure and partial pressures of the reactant gases were shown to influence the kinetics of crystal growth from the vapor phase. A two-inch diameter, molybdenum-element, muffle furnace was completed, which will enable growth of oriented ruby and sapphire crystals at least one inch in diameter. An experimental activation energy of 3.25 ev was determined for the overall growth process. A mechanism other than gaseous diffusion appears to be dominant for this system. Laminar flow, in the growth zone, is indicated by a calculated Reynolds number of 13.5. Vapor grown ruby and sapphire crystals exhibited a dislocation density reduction of one to three orders of magnitude over the flame fusion substrates. It was observed that dislocation densities decreased with increasing thickness of vapor growth.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 31, 1964
- Accession Number
- AD0613296
Entities
People
- Philip S. Schaffer