Method and apparatus for growing crystals by annealing the crystal after formation

Claim 1

A METHOD FOR SIMULTANEOUSLY GROWING AND ANNEALING A FRACTURE-FREE MONOCRYSTALLINE BODY IN A CRYSTAL-GROWING ZONE WHICH INCLUDES A HIGH TEMPERATURE FLAME, AND AN ELONGATED CHAMBER HAVING A CRYSTAL-GROWING SURFACE POSITIONED WITHIN SAID CHAMBER IN AXIAL ALIGNMENT WITH SAID FLAME, WHICH COMRISES THE STEPS OF: PASSING A FLOW OF POWDERED OXIDE MATERIAL THROUGH THE HIGH TEMPERATURE FLAME TO FUSE SAID MATERIAL, DIRECTING SAID FLAME AND FUSED MATERIAL TOWARD THE CRYSTALGROWING SURFACE, DEPOSITING AND ACCUMULATING SAID FUSED MATERIAL ONTO SAID GROWING SURFACE AT A TEMPERATURE AND FOR A TIME SUFFICIENT TO GROW A MONOCRYSTALLINE BODY THEREON WHILE SIMULTANEOUSLY LOWERING SAID GROWING BODY AT A RATE SUFFICIENT TO MAINTAIN A PREDETERMINED DISTANCE BETWEEN THE FLAME AND THE TOP PORTION OF THE GROWING BODY, CONTINUING TO LOWER THE GROWING BODY WHILE SIMULTANEOUSLY PROVIDING ADDITIONAL HEAT TO THE CRYSTAL-GROWING ZONE TO ACHIEVE A PREDETERMINED TEMPERATURE THEREIN, MAINTAINING AND CONTROLLING SAID PREDETERMINED TEMPERATURE FOR A TIME SUFFICIENT TO ATTAIN THE SIMULTANEOUS GROWTH AND ANNEAL OF A MONOCRYSTALLINE BODY OF DESIRED LENGTH, STOPPING SAI POWDER FLOW, CONTINUING TO LOWER SAID GROWN MONOCRYSTALLINE BODY ONTO SAID CRYSTAL-GROWING ZONE WHILE SIMULTANEOUSLY MAINTAINING SAID PREDETERMINED TEMPERATURE ANNEALING ENVIRONMENT, SIMULTANEOUSLY STOPPING SAID CRYSTAL MOVEMENT AND SAID FLAME WHILE CONTINUING TO MAINTAIN SAID GROWN CRYSTAL IN SAID PREDETERMINED TEMPERATURE ANNEALING ENVIRONMENT, COOLING SAID CRYSTAL TO COMPLETE SAID ANNEAL BY REDUCING SAID PREDETERMINED TEMPERATURE TO ROOM TEMPERATURE SLOWLY AT A PROGRAMMED RATE, AND REMOVING THE GROWN AND ANNEALED CRYSTAL FROM SAID GROWING ZONE

Claim 2

A METHOD FOR SIMULTANEOUSLY GROWING AND ANNEALING A FRACTURE-FREE MONOCRYSTALLINE BODY IN A CRYSTAL-GROWING ZONE WHICH INCLUDES A HIGH TEMPERATURE FLAME, AND AN ELONGATED CHAMBER HAVING A CRYSTAL-GROWING SURFACE POSITIONED WITHIN SAID CHAMBER IN AXIAL ALIGNMENT WITH SAID FLAME, WHICH COMRISES THE STEPS OF: PASSING A FLOW OF POWDERED OXIDE MATERIAL THROUGH THE HIGH TEMPERATURE FLAME TO FUSE SAID MATERIAL, DIRECTING SAID FLAME AND FUSED MATERIAL TOWARD THE CRYSTALGROWING SURFACE, DEPOSITING AND ACCUMULATING SAID FUSED MATERIAL ONTO SAID GROWING SURFACE AT A TEMPERATURE AND FOR A TIME SUFFICIENT TO GROW A MONOCRYSTALLINE BODY THEREON WHILE SIMULTANEOUSLY LOWERING SAID GROWING BODY AT A RATE SUFFICIENT TO MAINTAIN A PREDETERMINED DISTANCE BETWEEN THE FLAME AND THE TOP PORTION OF THE GROWING BODY, CONTINUING TO LOWER THE GROWING BODY WHILE SIMULTANEOUSLY PROVIDING ADDITIONAL HEAT TO THE CRYSTAL-GROWING ZONE TO ACHIEVE A PREDETERMINED TEMPERATURE THEREIN, MAINTAINING AND CONTROLLING SAID PREDETERMINED TEMPERATURE FOR A TIME SUFFICIENT TO ATTAIN THE SIMULTANEOUS GROWTH AND ANNEAL OF A MONOCRYSTALLINE BODY OF DESIRED LENGTH, STOPPING SAI POWDER FLOW, CONTINUING TO LOWER SAID GROWN MONOCRYSTALLINE BODY ONTO SAID CRYSTAL-GROWING ZONE WHILE SIMULTANEOUSLY MAINTAINING SAID PREDETERMINED TEMPERATURE ANNEALING ENVIRONMENT, SIMULTANEOUSLY STOPPING SAID CRYSTAL MOVEMENT AND SAID FLAME WHILE CONTINUING TO MAINTAIN SAID GROWN CRYSTAL IN SAID PREDETERMINED TEMPERATURE ANNEALING ENVIRONMENT, COOLING SAID CRYSTAL TO COMPLETE SAID ANNEAL BY REDUCING SAID PREDETERMINED TEMPERATURE TO ROOM TEMPERATURE SLOWLY AT A PROGRAMMED RATE, AND REMOVING THE GROWN AND ANNEALED CRYSTAL FROM SAID GROWING ZONE

Claim 3

A method for simultaneously growing and annealing a fracture-free monocrystalline body in a crystal-growing zone which includes a high temperature flame, and an elongated chamber having a crystal-growing surface positioned within said chamber in axial alignment with said flame, which comprises the steps of: passing a flow of powdered oxide material through the high temperature flame to fuse said material, directing said flame and fused material toward the crystal-growing surface, depositing and accumulating said fused material onto said growing surface at a temperature and for a time sufficient to grow a monocrystalline body thereon while simultaneously lowering said growing body at a rate sufficient to maintain a predetermined distance between the flame and the top portion of the growing body, continuing to lower the growing body while simultaneously providing additional heat to the crystal-growing zone to achieve a predetermined temperature therein, maintaining and controlling said predetermined temperature for a time sufficient to attain the simultAneous growth and anneal of a monocrystalline body of desired length, stopping said powder flow, continuing to lower said grown monocrystalline body onto said crystal-growing zone while simultaneously maintaining said predetermined temperature annealing environment, simultaneously stopping said crystal movement and said flame while continuing to maintain said grown crystal in said predetermined temperature annealing environment, cooling said crystal to complete said anneal by reducing said predetermined temperature to room temperature slowly at a programmed rate, and removing the grown and annealed crystal from said growing zone.

Claim 4

A method for simultaneously growing and annealing a fracture-free monocrystalline body in a crystal-growing zone which includes a high temperature flame, and an elongated chamber having a crystal-growing surface positioned within said chamber in axial alignment with said flame, which comprises the steps of: passing a flow of powdered oxide material through the high temperature flame to fuse said material, directing said flame and fused material toward the crystal-growing surface, depositing and accumulating said fused material onto said growing surface at a temperature and for a time sufficient to grow a monocrystalline body thereon while simultaneously lowering said growing body at a rate sufficient to maintain a predetermined distance between the flame and the top portion of the growing body, continuing to lower the growing body while simultaneously providing additional heat to the crystal-growing zone to achieve a predetermined temperature therein, maintaining and controlling said predetermined temperature for a time sufficient to attain the simultAneous growth and anneal of a monocrystalline body of desired length, stopping said powder flow, continuing to lower said grown monocrystalline body onto said crystal-growing zone while simultaneously maintaining said predetermined temperature annealing environment, simultaneously stopping said crystal movement and said flame while continuing to maintain said grown crystal in said predetermined temperature annealing environment, cooling said crystal to complete said anneal by reducing said predetermined temperature to room temperature slowly at a programmed rate, and removing the grown and annealed crystal from said growing zone.