Chervonyj I. Scientific fundamentals and development of a competitive technology of single crystal silicon by the method of special electrometallurgy (float – zone melting)

The thesis is dedicated to the growth of high quality dislocation – free silicon single crystals of a large diameter by the method of float zone melting. In the work new trends on creation of optimal heat conditions and growth regimes have been developed. New decisions for heat systems and apparatus for reproducable and stable growth and doping silicon single crystals have been suggested. Numerical method for determination of regimes for silicon rod purification and doping have been found and a criterion was developed for evaluation of their suitability in production of target quality silicon single crystals. A new theory has been suggested for generation of microdefects in dislocation – free silicon single crystals which was based on interaction of point defects with impurity atoms. It was found that microdefects of A– and D– type have different physical nature and their formation depends on conditions of single crystal growth. A final stage of the work was development of the technology for production of dislocation – free single crystals of 105 mm in diameter with parameters complex being on the level of the best foreign samples. The technology has been introduced at Zaporozhye titanium and magnesium combine (Zaporozhye–city, Ukraine) in a full volume. The technology for doping has been adopted at Podolsk chemical–metallurgical works (Podolsk, Russia).