Growth of uniform composition semiconductor crystals

Claim 1

THE METHOD OF GROWING UNCONSTRAINED SINGLE CRYSTALS OF A SEMICONDUCTOR MATERIAL SELECTED FROM THE GROUP CONSISTING OF GERMANIUM AND SILICON AND HAVING A SUBSTANTIALLY CONSTANT CONCENTRATION OF ELEFTRICALLY SIGNIFICANT ACTIVATOR IMPURITIES THEREIN WHICH METHOD COMPRISES PLACING A QUANTITY OF THE SEMICONDUCTOR MATERIAL IN A VERTICAL CRUCIBLE THE DEPTH OF WHICH IS GREATER THAN ITS DIAMETER, THE SEMICONDUCTOR HAVING A CONCENTRATION OF ACTIVATOR MATERIAL THEREIN EQUAL TO THE CONCENTRATION OF ACTIVATOR MATERIAL DESIRED IN THE GROWN SINGLE CRYSTAL, RAISING THE TEMPERATURE OF THE SEMICONDUCTOR ABOVE THE FUSION POINT TO CAUSE IT TO BECOME MOLTEN, RAPIDLY LOWERING THE TEMPERATURE OF THE SIMICONDUCTOR TO A TEMPERATURE BELOW ITS FUSION POINT BUT ABOVE TEMPERATURE AT WHICH THE SEMICONDUCTOR REMAINS PLASTIC TO CAUSE THE SEMICONDUCTOR TO FREEZE NON-DIRECTIONALLY INTO A SOLID BUT PLASTIC MASS, RAISING THE TEMPERATURE OF A ZONE OF THE FROZEN SEMICONDUCTOR MASS ADJACENT TO AND BOUNDED BY THE UPPER SURFACE THEREOF ABOVE THE FUSION TEMPERATURE THEREOF WHILE MAINTAINING THE REMAINDER OF THE FROZEN MASS AT A TEMPERATURE BELOW ITS FUSION POINT BUT ABOVE THE TEMPERATURE AT WHICH THE SEMICONDUCTOR REMAINS PLASTIC TO ESTABLISH A MOLTEN ZONE ADJACENT THE UPPER SURFACE THEREOF, CONTACTING THE SURFACE OF THE MOLTEN ZONE WITH A SEED CRYSTAL OF THE SEMICONDUCTOR, AND GROWING A SINGLE CRYSTALLINE INGOT OF SEMICONDUCTOR BY SEED CRYSTAL WITHDRAWAL FROM THE MOLTEN ZONE WHILE REPLENISHING THE MOLTEN ZONE FROM THE UNMELTED PORTION OF THE SEMICONDUCTOR MASS TO MAINTAIN THE MOLTEN ZONE AT A SUBSTANTIALLY CONSTANT VOLUME.