Accession Number:

ADA003645

Title:

The Growth of SiC Crystals from Vapor by the Bridgman-Stockbarger Method.

Descriptive Note:

Physical sciences research papers,

Corporate Author:

AIR FORCE CAMBRIDGE RESEARCH LABS HANSCOM AFB MASS

Personal Author(s):

Report Date:

1974-09-24

Pagination or Media Count:

36.0

Abstract:

From the dissociation curve P vs. T, an equation for the rate of raising the pressure P of the binary vapor for obtaining the required linear growth rate of the crystal of c centimeters per hour is derived. It is shown that the rate is nearly proportional to P. Modifications of the furnace since the last report Mat. Res. Bull. 4, S85, 1969 are described. Justification for the use of helium as the inert ambient gas is given. Two techniques are used 1 growing with constant temperature of the crucible point and 2 growing with constant pressure of the sublimation bottle. To date, only polycrystalline boules consisting of large grains have been obtained. It is believed, however, that with certain technological improvements the methods that are developed here will ultimately yield single crystal boules. As a by-product, small cubic crystals, about one mm in the largest dimension, with good quality faces cube and octahedron have been obtained.

Subject Categories:

  • Crystallography

Distribution Statement:

APPROVED FOR PUBLIC RELEASE