Process for making monocrystalline silicon
Abstract
Abstract DISCLOSED IS A PROCESS FOR MAKING MONOCRYSTALLINE SILICON IN A ZONE REFINING OPERATION. IN THIS PROCESS, A GASEOUS MIXTURE COMPRISING PREDETERMINED VOLUME PERCENTAGES OF HYDROGEN GAS AND A SELECTED INERT GAS, SUCH AS ARGON, IS INTRODUCED OR "PURGED" INTO A CHAMBER OF A ZONE REFINER BOTH PRIOR TO AND DURING A SILICON ZONE REFINING OPERATION. THE PRESENCE OF A SELECTED VOLUME PERCENTAGES OF NO MORE THAN 5% HYDROGEN GAS IN THIS GASEOUS MIXTURE WHICH IS PURGED INTO THE ZONE REFINING CHAMBER HAS BEEN FOUND TTO ELIMINATE SWIRLS IN THE SILICON WHICH HAD PREVIOUSLY BEEN DISCOVERED AFTER ETCHING ZONE REFINED SILICON WAFERS PROCESSED IN A ZONE REFINING OPERATION USING NO HYDROGEN GAS.
Inventors
- 👤 W Campbell
Bibliographic Details
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