METHOD OF FORMING A TEMPERATURE GRADIENT IN A THERMAL UNIT OF A FURNACE FOR GROWING FLUORIDE CRYSTALS AND A DEVICE FOR ITS IMPLEMENTATION Russian patent published in 2022 - IPC C30B11/00 C30B29/12 

FIELD: growing crystals.

SUBSTANCE: invention relates to the technology of growing fluoride crystals by vertical directional crystallization (Bridgman method) in the presence of a temperature gradient in the crystallization zone and to a device for its implementation. Method of forming a temperature gradient in a thermal unit of a furnace for growing fluoride crystals involves taking a device in the form of copper pipe 3, at one end it is cooled with water by means of a water-cooled copper tube 4 soldered on it, and at the other end it is coated with heat-insulating material 5, and it is installed inside heater 1 from the lower end so that the end of copper pipe 3 with heat-insulating material 5 enters the lower part of heater 1; then, cooling water is switched on, which is directed through water-cooled copper tube 4, for cooling first the end of copper tube 3, and then the whole copper tube 3 due to thermal conductivity of its material; wherein on one side heat-insulating material 5 prevents heat exchange between copper pipe 3 and heater 1, on the other side — cooling is carried out by means of water-cooled copper tube 4, as a result, a temperature gradient of 110–130°C/cm at transition from heater 1 to copper pipe 3, then measuring the temperature along the height inside heater 1 with the said device in the form of copper pipe 3 inserted into it using a thermocouple installed at the bottom of the crucible with the melt moved along the height of heater 1 from the hot zone into the cooled copper pipe 3, and the measurement results are used to determine the temperature gradient in the growth zone for the further crystal growth process. Method is carried out in a device consisting of copper pipe 3 with diameter of 30–40 mm, length of 80–100 mm and a wall thickness of 2–4 mm, wherein at least 1.5 turns of water-cooled copper tube 4 with inner diameter of 4–6 mm are wound on one end of copper pipe 3, water-cooled copper tube 4 is soldered to copper pipe 3 along the whole length of winding and is connected to supply hose by one end cooling water, and the other is to the water drain hose with the possibility of cooling first the lower part of copper pipe 3, and then the entire copper pipe 3 due to the thermal conductivity of its material; wherein outer part of copper pipe 3 from water-cooled copper pipe 4 to end on its other end is coated with heat-insulating material 5 to prevent heat exchange between copper pipe 3 and heater 1.

EFFECT: high temperature gradient creates optimum conditions for growing monocrystals of double fluorides at a higher rate.

2 cl, 4 dwg, 2 ex