BETA-SILICON CARBIDE AND ITS POTENTIAL FOR DEVICES
Abstract
The resistivities of crystals of beta-SiC grown during this quarter increased nearly another order of magnitude over those obtained during the last report period. This increase, from approximately .5 to 3.8 ohm-cm, accompanied progress in minimizing the sources of N contamination during crystal growth. Routine degassing of graphite crucibles at 2150 C and 10 to the -5th power mm Hg within the crystal grower was achieved. Analyses of Si stock used for crystal growth revealed N contents as high as 43 ppm. Specially purified low-N-content Si rod was obtained, and a vacuum extraction procedure for removing any remaining dissolved N was developed. Analyses of ordinary standard tank He used for the crystal growing furnace atmosphere revealed N contamination as high as 600 ppm. Analyzed premium grade He containing less that 10 ppm N was received from suppliers and a new bakeable purification train is being constructed to assure a N-free furnace atmosphere. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 15, 1962
- Accession Number
- AD0289015
Entities
People
- W.e. Nelson
Organizations
- SRI International