First results of s.i. GaAs single crystal growth applying the vapour pressure controlled Czochralski method

The purpose of this paper is to show the current stage of development of the Vapour Pressure Controlled Czochralski Method (VCZ) at the Institute of Crystal Growth (IKZ) in Berlin. First 3" s.i. GaAs crystals, grown in our laboratory, will be presented. The paper briefly summarizes investigations on i) crystal perfection i.e., etch pit density (EPD), cell structure, precipitates and, ii) electrical data, The properties of the crystals are acceptable for s.i. GaAs. An average EPD in the range from 1 to 2/spl times/10/sup 4/ cm/sup -2/ is just achieved but, does not yet match the requirements of very low EPD material.