Production of mono-crystal semiconductor bodies

Claim 1

PROCESS OF PREPARING A BODY OF MONO-CRYSTAL SILICON CONTAINING AN IMPURITY ACTIVATOR SELECTED FROM THE GROUP CONSISTING OF ALUMINUM AND ANTIMONY, WHICH CONSISTS IN LOCATING AN INGOT OF SUBSTANTIALLY PURE SILICON IN A VERTICALLY DISPOSED CLOSELY SURROUNDING QUARTZ TUBE, MAINTAINING A NON-OXIDIZING ATMOSPHERE AROUND SAID TUBE AND INGOT, LOCATING A PELLET OF SILICON CONTAINING SAID ACTIVATOR IN CONTACT WITH THE UPPER SURFACE OF SAID INGOT, INDUCTIVELY HEATING A ZONE INCLUDING SAID PELLET AND THE UPPER END OF SAID INGOT SO AS TO CAUSE MELTING OF SAID PELLET AND LOCALISED MELTING OF SAID INGOT, INTRODUCING A SEED CRYSTAL OF SILICON INTO THE MOLTEN MASS, AND WITHDRAWING SAID SEED CRYSTAL FROM SAID ZONE WHEREBY MATERIAL ADHERENT TO SAID SEED CRYSTAL AND CONTAINING SAID IMPURITY ACTIVATOR SOLIDIFIES WHILST ACQUIRING THE MONO-CRYSTAL STRUCTURE OF SAID SEED CRYSTAL, AND HEATING THE INGOT PROGRESSIVELY LONGITUDINALLY THEREOF AS THE UPPER END OF THE INGOT MOVES CORRESPONDINGLY LONGITUDINALLY OF THE INGOT WITH THE WITHDRAWAL OF MOLTEN MATERIAL WITH THE WITHDRAWAL OF THE SEED CRYSTAL, THE HEATING OF THE INGOT BEING MAINTAINED SOLELY IN SAID ZONE TO ASSURE THAT ONLY THE UPPER END OF THE INGOT NECESSARY FOR THE CONTINUANCE OF THE SUPPLY OF MOLTEN MATERIAL ADHERENT TO, AND FOR SOLIDIFICATION BEHIND THE BODY WITHDRAWN FROM SAID TUBE, AND FOR THE MAINTENANCE OF A MOLTEN MASS CONTAINING A PREDETERMINED CONCENTRATION OF SAID ACTIVATOR IS AT ANY TIME IN MOLTEN STATE CONTACT WITH SAID TUBE.