Journal of the American Ceramic Society · 1965 · 30 citations · 1 references
Natural SciencesMaterials EngineeringMaterials ScienceCeramic MaterialsCrystal StructureMaterials ChemistryAluminum OxidesChemical Vapor DepositionCrystal ChemistryCrystal GrowthDislocation MechanicsEpitaxial GrowthAlpha AluminaAlumina CeramicsCrystal PerfectionDislocation DensityEpitaxial Growth KineticsNeutron ActivationSubstrate Temperature EffectsTotal Pressure
A chemical vapor‐deposition technique was developed for epitaxial growth of α‐Al 2 O 3 single crystals utilizing the reaction: image Oriented crystals weighing up to 5 g were grown between 1550° and 1800°C. The growth rate for constant gas compositions and flow rates increased with an increase in temperature. Etch pit studies showed an average dislocation density of 5 × 10 3 dislocations/cm 2 . Spectrochemical and neutron activation analyses indicated total impurity levels below 35 ppm. Crystalline perfection and morphology were controlled by substrate temperature, total pressure, and reactant gas partial pressures.
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