Epitaxial growth of germanium and silicon single crystal films from the vapor phase

Single crystal films of germanium and silicon have been grown on suitably prepared substrates by the hydrogen reduction of the respective tetrachlorides. The problem of obtaining single crystal growth is shown to be a major function of substrate surface preparation, temperature of substrate and of the tetrachlorides. Factors affecting conductivity type, resistivity and film thickness are discussed, together with measurement techniques. Current limiters and other devices made, utilizing the single crystal films, are discussed and results presented.