CN-117822089-B - Crystal growth device containing special-shaped partition plate and special-shaped partition plate

CN117822089BCN 117822089 BCN117822089 BCN 117822089BCN-117822089-B

Abstract

The invention relates to a crystal growth device with a special-shaped baffle plate and the special-shaped baffle plate. The growth device comprises a furnace shell, a heat preservation layer, a crucible and a heating body, wherein the heat preservation layer is arranged in the furnace shell and forms a closed hollow cavity to provide a crystal growth operation space, the heating body is arranged on the inner wall of the heat preservation layer and is used for providing a heat source for crystal melting, the crucible comprises an equal diameter part fixedly arranged from top to bottom, a shoulder part and a seed crystal part, the radial dimension of the seed crystal part is smaller than that of the equal diameter part, the special-shaped partition plate is arranged below the heating body and is used for dividing the hollow cavity into different temperature areas to enable crystals to grow in the area corresponding to the special-shaped partition plate, the special-shaped partition plate comprises an upper narrow part fixedly arranged from top to bottom, a middle slope part and a lower wide part, the radial dimension of the lower wide part is larger than that of the upper narrow part, and the middle slope part of the special-shaped partition plate and the shoulder part of the crucible are arranged in parallel to each other to solve the supercooling of the wall surface of the shoulder part of the crucible and ensure smooth crystal crystallization.

Inventors

SU LIANGBI
WANG PENGFEI
JIANG DAPENG
ZHANG ZHONGHAN
QIAN XIAOBO
TANG FEI
WANG YIFENG

Assignees

中国科学院上海硅酸盐研究所

Dates

Publication Date: 20260512
Application Date: 20231204

Claims (9)

1. The crystal growth device comprises a furnace shell, a heat preservation layer, a crucible and a heating body, wherein the heat preservation layer is arranged in the furnace shell and forms a closed hollow cavity to provide a crystal growth operation space, the heating body is arranged on the inner wall of the heat preservation layer and is used for providing a heat source for crystal melting, the crucible comprises an equal diameter part, a shoulder part and a seed crystal part which are fixedly connected from top to bottom, the radial dimension of the seed crystal part is smaller than that of the equal diameter part, The heating element comprises a hollow cavity, a heating element, a special-shaped partition plate, a central slope part, a lower wide part and a central slope part, wherein the special-shaped partition plate is arranged below the heating element and is used for dividing the hollow cavity into different temperature areas so that crystals grow in the areas corresponding to the special-shaped partition plate, the special-shaped partition plate comprises an upper narrow part, a central slope part and a lower wide part which are fixedly arranged from top to bottom, the radial size of the lower wide part is larger than that of the upper narrow part, and the radial size of the lower wide part is larger than that of the upper narrow part, wherein The upper narrow part of the special-shaped partition plate is arranged approximately in parallel with the constant diameter part of the crucible, the middle slope part of the special-shaped partition plate is arranged approximately in parallel with the shoulder part of the crucible, the lower wide part is arranged approximately in parallel with the seed crystal part of the crucible, wherein The inner wall surface of the upper narrow part is arranged on the radial outer side of the inner wall surface of the heating body, or the inner wall surface of the upper narrow part is radially flush with the inner wall surface of the heating body.
2. The crystal growth apparatus having a shaped separator according to claim 1, wherein when the inner wall surface of the upper narrow portion is provided outside the inner wall surface of the heat generating body, the inner wall surface of the upper narrow portion is provided outside the outer wall surface of the heat generating body.
3. The crystal growth apparatus having a shaped baffle plate according to claim 1, wherein the shaped baffle plate is made of a low heat conductive material to achieve division of the hollow cavity into different temperature regions, wherein The surface of the special-shaped partition board is fixedly provided with a high-reflection material.
4. A crystal growth apparatus comprising a shaped baffle plate according to any one of claims 1-3, wherein the inclination angle of the middle slope of the shaped baffle plate differs from the inclination angle of the shoulder of the crucible by no more than 5 °.
5. A crystal growth apparatus comprising a shaped baffle plate according to any one of claims 1-3, wherein the height of the shaped baffle plate is 3-4 times the height of the shoulder portion of the crucible.
6. A crystal growth apparatus comprising a shaped baffle plate according to any one of claims 1-3, wherein the radial distance between the lower wide portion of the shaped baffle plate and the constant diameter portion of the crucible is 5-15mm.
7. A crystal growth apparatus comprising a profiled baffle plate according to any one of claims 1-3, wherein the furnace shell is adapted to insulate the external environment, wherein The furnace shell is provided with an interlayer and is filled with circulating cooling water so as to prevent workers from being scalded by the high temperature of the outer wall of the furnace shell when the crystal growth is operated.
8. The utility model provides a special-shaped baffle, sets up in a crystal growth device that contains special-shaped baffle, growth device includes stove outer covering, heat preservation, crucible and heat-generating body, the heat preservation sets up in the stove outer covering and forms a airtight cavity in order to provide crystal growth operation space, the heat-generating body sets up and is used for providing the heat source that crystal melts on the inner wall of growth furnace, the crucible includes from the top down links firmly the isodiametric portion that sets up, puts shoulder and seed crystal portion, the radial dimension of seed crystal portion is less than isodiametric portion, its characterized in that, The special-shaped partition board is arranged below the heating body and used for dividing the hollow cavity into different temperature areas so that crystals grow in the areas corresponding to the special-shaped partition board, the special-shaped partition board comprises an upper narrow part, a middle slope part and a lower wide part which are fixedly connected from top to bottom, and the radial size of the lower wide part is larger than that of the upper narrow part, wherein The middle slope part of the special-shaped partition plate and the shoulder part of the crucible are arranged in parallel, and the inner wall surface of the upper narrow part is arranged on the radial outer side of the inner wall surface of the heating body, or the inner wall surface of the upper narrow part is radially flush with the inner wall surface of the heating body so as to increase the reflection heat quantity from the special-shaped partition plate to the shoulder part.
9. The profiled baffle according to claim 8, wherein the upper narrow portion of the profiled baffle has a width of 3-15mm and the lower wide portion of the profiled baffle has a height of 5-20mm.

Description

Crystal growth device containing special-shaped partition plate and special-shaped partition plate Technical Field The invention relates to the technical field of crystal growth by utilizing a crucible descent method, in particular to a crystal growth device with a special-shaped baffle plate and the special-shaped baffle plate. Background Referring to fig. 1, there is provided a crystal growth apparatus using a crucible descent method, the apparatus mainly comprising a furnace shell, a heat insulation layer, a heating body, a partition plate, a crucible and a support rod. The upper space in the heat preservation layer is provided with heat by the heating element, the lower space is taken away by cooling water in the supporting rod, and the middle annular partition plate separates the upper hot area from the lower cold area. In the crucible descent method, the melt solidifies and crystallizes continuously in the middle gradient zone as the crucible descends slowly. For cost and quality reasons, practical crystal growth is usually based on a small-sized seed crystal, which gradually expands to a target large size after successful inoculation, so that the growth crucible at this time needs to be designed as a small-diameter seed crystal portion, a shoulder portion for transition from small seed crystal to large crystal growth, and a final-sized large-diameter constant-diameter portion. However, this results in that when the crystal grows to the shoulder portion, the shoulder portion wall surface of the crucible is limited to the shape of an inverted cone, and not only the heat radiation of the heat generating body cannot be directly received, but also the heat radiation is radiated toward the lower cold zone, resulting in supercooling of the shoulder portion wall surface of the crucible. Supercooling of the crucible wall can cause a series of undesirable consequences such as dishing of the solid-liquid interface into the crystal, excessive radial temperature differentials in the crystal below the interface, dislocation propagation induced by excessive radial temperature differentials in the crystal below the interface, and formation of flow cells in the melt above the interface from the edge of the crucible to the center of the crucible, carrying impurities toward the center. In addition, supercooling of the crucible wall can induce wall surface nuclei to generate mixed crystals, and the concave interface can further lead the wall surface mixed crystals to spread towards the center of the crystal, so that the quality of the final crystal and the caliber of the single crystal are seriously affected. In the prior art, to solve the problems of supercooling of the shouldering wall surface, sinking of a solid-liquid interface and the like in the shouldering growth stage of a crucible descent method, kuppurao et al propose to wrap a crucible shouldering and seed crystal part by using a crucible support with heat insulation around and high heat conduction of an inner core, so that heat is only pumped axially from the bottom of a crystal to avoid radial dissipation of heat from the shouldering wall surface, the method can indeed improve supercooling of the crucible wall and obtain a convex interface in the shouldering growth stage, but the crucible seed crystal and the shouldering part are wrapped by the crucible heat insulation, and the phase change latent heat cannot be effectively removed by water cooling/air cooling pumping only at the bottom in the middle and later stages of the equal-diameter growth, so that the shape of the solid-liquid interface is more deteriorated than that of the crucible support which is not used in the middle and later stages. Jansiski, volz, etc. propose to arrange an additional local heater above the intersection of the solid-liquid interface and the crucible wall, and avoid supercooling of the crucible wall near the growth interface by direct targeted local heating, so that the ideal convex interface morphology can be obtained in the whole course. However, the crucible shape is changed all the time from seed crystal to shoulder and then to the constant diameter growth stage, so that the whole growth process is ensured that the local heater is always positioned above and near the intersection of the solid-liquid interface and the crucible wall, and the practical implementation difficulty is high. Disclosure of Invention The invention provides a crystal growing device with a special-shaped baffle plate and the special-shaped baffle plate, which at least solve one problem of supercooling of the wall surface of a crucible shoulder and sinking of a growing interface during crystal growth, and do not prevent other growing stages from obtaining a convex interface. In a first aspect of the present invention, there is provided a crystal growth apparatus comprising a furnace shell, an insulating layer, a crucible and a heat generating body, wherein the insulating layer is disposed in the furnac