Method of producing hyperpure silicon, silicon carbide and germanium

Claim 1

IN THE PROCESS OF PREPARING A SEMICONDUCTOR FROM THE GROUP CONSISTING OF SILICON, SILICON CARBIDE AND GERMANIUM, IN WHICH THE SEMICONDUCTOR IS PRECIPITATED UPON A HOT CARRIER ROD OF THE SAME MATERIAL, BY CHEMICAL CONVERSION FROM A GASEOUS COMPOUND OF SAID SEMICONDUCTOR MATERIAL WITH THE AID OF A CARRIER GAS ACTING AS A REDUCING AGENT, WITHIN AN AT LEAST PARTIALLY TRANSPARENT VESSEL AT LEAST PARTIALLY COMPRISED OF A QUARTZ, THE IMPROVEMENT GROUP CONSISTING OF GLASS AND QUARTZ, THE IMPROVEMENT WHICH SUBSTANTIALLY PREVENT THE PRECIPITATION OF SEMICONDUCTOR MATERIAL ON THE INNER WALL OF THE REACTION VESSEL, AND WHICH COMPRISES THE SEQUENTIAL STEPS OF (A) PASSING A PARTIAL CURRENT OF CARRIER GAS THROUGH THE REACTION VESSEL PRIOR TO INITIATING THE PRECIPITATION PROCESS. (B) HEATING THE CARRIER RODS TO INCANDESCENT TEMPERATURE IN THE CARRIER GAS CURRENT OF STEP (A), (C) INCREASING THE CARRIER GAS CURRENT TO THE FULL AMOUNT REQUIRED FOR NORMAL PRECIPITATION OPERATION, (D) AFTER THE INNER WALL OF THE REACTION VESSEL HAS REACHED A TEMPERATURE OF ABOUT 300* C., SUPPLYING GASEOUS SEMICONDUCTOR COMPOUND IN AN AMOUNT SO THAT THE MOLAR RATIO OF SEMICONDUCTOR COMPOUND TO CARRIER GAS IS LESS THAN ABOUT 0.2:1, AND (E) COMMENCING AND PERFORMING THE PYROLYTIC PRECIPITATION.