Process for the continuous production of silicon rods or tubes by

Abstract

A process for the continuous production of silicon rods or tubes by the dsition of silicon from the gaseous phase on the inner wall of a carrier tube heated to the deposition temperature, in which a cooled, hollow metal cylinder is placed in a reactor having one open end, and a flexible band, substantially resistant to silicon at the deposition temperature, is continuously wound onto the cylinder in an overlapping manner at an angle of pitch from 5.degree. to 40.degree. so as to form the carrier tube for the silicon to be deposited; the tube is continuously drawn off the metal cylinder by a rotary traction movement and the portion of the tube adjacent the metal cylinder and still in the reactor is heated to the deposition temperature of about 1050.degree. to 1250.degree. C, while at the same time the gaseous mixture is passed for decomposition through the tube under a pressure exceeding the external atmospheric pressure by 0.01 - 1 bar, thus causing the inside of the tube gradually to be filled partly or entirely with the silicon as the decomposition of the gas mixture proceeds, and finally the Si-filled tube is continuously withdrawn from the reactor at the open end thereof, with the recovery of the silicon rod or tube by removal of the carrier tube through etching, burning off, or sandblasting.