Process for the deposition of pure semiconductor material

A process for the deposition of pure semiconductor material, particularly silicon, by thermal decomposition of gaseous compounds of the semiconductor material on thin rods serving as carrier bodies heated to the decomposition temperature of the compounds by the passage of an electrical current comprising:

• providing an open topped reaction chamber whose interior surfaces are either of silver or silver plated and mounting said electrially heatable carrier rods therein;
• providing a cover cylinder about the reaction chamber and forming therewith a closed annular chamber;
• attaching a heating element at said open top and preheating said carrier rods;
• sealing the open top and removing said heating element;
• passing a heating current through the carrier rods;
• passing a coolant through the annular chamber;
• feeding said gaseous compounds into the reaction chamber and maintaining an excess pressure of 1-16 bar therein.