Technology and thermomechanics in growing tubular silicon single crystals

Abstract

The problem of growing high-resistance low-dislocation tubular silicon single crystals for non-planar manufacturing technologies of epitaxial p-n junctions and the production of new-generation power semiconductor devices is considered. The possibilities of Stepanov method for growing volumetric profiled crystalline products, the application of which is based on the use of shapers of various designs, are discussed. In particular, the shortcomings of shapers associated with the melt contamination by foreign particles and impurities are discussed. Therefore, the main attention is paid to the use of equipment that implements crystal growth from a melt without a shaper by Czochralski method. The processes of thermal mechanics are preliminary analyzed in relation to the existing and well-established process of growing polycrystalline highly dislocation silicon pipes of large diameter by Czochralski method for epitaxial reactors.It is noted that the growth of tubular low-dislocation small diameter silicon single crystals requires a significant modernization of the standard hot zone, which in this work is implemented for “REDMET-10” Czochralski furnace. By means of computer simulation, thermal mechanical processes are calculated for such a modernized Czochralski furnace. The parameters of grown tubular silicon single crystals are characterized, and their manufacturing suitability for power semiconductor devices using nonplanar technology is assessed.