CN-122013299-A - Concentration gradient crystal growth method and crystal growth system

CN122013299ACN 122013299 ACN122013299 ACN 122013299ACN-122013299-A

Abstract

The application provides a concentration gradient crystal growth method and a crystal growth system, wherein the concentration gradient crystal growth method calculates the real-time replenishment rate of each component raw material through preset crystal concentration change trend data, the real-time growth rate of the currently grown crystal obtained by adopting a pulling method and the chemical formula ratio for generating the crystal, and performs raw material replenishment through controlling a valve of a material replenishment unit for supplying raw materials to a crucible assembly, thereby obtaining the crystal with the preset crystal concentration change trend. Therefore, based on the continuous feeding of the real-time feeding rate of the raw materials of each component, crystals with gradually changed growth concentration and longer size can be obtained, the growth cost is reduced, and meanwhile, the crystal growth process is always kept at the same position due to the continuous feeding, the growth interface is stable, and the quality of the crystals is ensured.

Inventors

ZHANG JIANJUN
TANG HAITAO
LIU GANG

Assignees

成都新源汇博光电科技有限公司

Dates

Publication Date: 20260512
Application Date: 20260225

Claims (10)

1. A method of graded crystal growth comprising: Acquiring preset crystal concentration change trend data; Acquiring weight data of a currently grown crystal obtained by adopting a Czochralski method; determining a real-time growth rate of the crystal based on the weight data; determining the real-time replenishment rate of each component raw material corresponding to the crystal based on the preset crystal concentration change trend data, the real-time growth rate and the chemical formula ratio of the generated crystal; controlling a valve of a feeding unit for feeding raw materials to the crucible assembly, and feeding each component raw material at the real-time feeding rate to obtain crystals with a preset crystal concentration variation trend, wherein the melt liquid level in the crucible assembly is always kept at the same height.
2. The method according to claim 1, wherein the crystals of the predetermined crystal concentration variation trend are crystals in which the concentration of the first component raw material gradually increases in the direction of the crystal axis of the crystals; the step of controlling the valve of the feeding unit for feeding the raw material to the crucible assembly to feed each component raw material at the real-time feeding rate so as to obtain crystals having a predetermined trend of variation in crystal concentration includes: And controlling the valve to feed each component raw material at the real-time feeding rate so as to obtain crystals with the concentration of the first component raw material gradually increasing along the crystal axis direction.
3. The method of claim 1, wherein the crucible assembly comprises a first crucible and a second crucible, the first crucible and the second crucible being nested and in communication with each other, the first crucible being located inside the second crucible; the step of controlling the valve of the feeding unit for feeding the raw material to the crucible assembly to feed each component raw material at the real-time feeding rate so as to obtain crystals having a predetermined trend of variation in crystal concentration includes: and supplementing corresponding component raw materials into the second crucible at the real-time supplementing rate, wherein the component raw materials flow into the first crucible through the through hole of the first crucible.
4. A method of growing crystals, comprising: Acquiring weight data of a currently grown crystal obtained by adopting a Czochralski method; determining a real-time growth rate of the crystal based on the weight data; Determining the real-time replenishment rate of each component raw material corresponding to the crystal based on the real-time growth rate and the chemical formula ratio of the generated crystal; Controlling a valve of a feeding unit for feeding raw materials to the crucible assembly, and feeding each component raw material at the real-time feeding rate so as to make the concentration of each part of the crystal uniform, wherein the melt liquid level in the crucible assembly is always kept at the same height.
5. The method of claim 4, wherein the crystals correspond to a first component feedstock and a second component feedstock, the first component feedstock being segregated along an axial direction of the crystals.
6. The crystal growth system is characterized by comprising a crystal growth unit, a feeding unit, a detection unit and a control unit; The crystal growth unit comprises a lifting assembly and a crucible assembly, wherein the lifting assembly is positioned above the opening end of the crucible assembly; the feeding unit comprises a plurality of feeding bins and a plurality of pipelines respectively communicated with each feeding bin, and each pipeline is provided with a valve; the detection unit is used for monitoring the weight of the crystal on the lifting assembly in real time and generating weight data; The control unit is electrically connected with the detection unit and the valve respectively and is used for receiving the weight data and controlling the valve at least based on the weight data.
7. The crystal growing system of claim 6 wherein the crucible assembly includes a first crucible and a second crucible nested and in communication with each other, the first crucible being positioned inside the second crucible, wherein the first crucible is used to grow the crystal and the second crucible is used to replenish the feedstock corresponding to the crystal.
8. The crystal growth system of claim 7, wherein the bottom of the first crucible is provided with at least four symmetrically distributed through holes for communicating with the second crucible.
9. The crystal growth system of claim 6, wherein the control unit includes crystal growth software for determining a real-time growth rate of the crystal based on the weight data and a programmable logic controller for controlling the valve based at least on the real-time growth rate.
10. The crystal growth system of claim 6, wherein the valve comprises a precision metering valve.

Description

Concentration gradient crystal growth method and crystal growth system Technical Field The application relates to the technical field of crystal growth, in particular to a concentration gradient crystal growth method and a crystal growth system. Background In the conventional process of growing neodymium-doped yttrium aluminum garnet crystals (Nd: YAG crystals) by a pulling method, a one-time charging mode is generally adopted. Raw materials are continuously consumed as the crystal grows. However, since the segregation coefficient of neodymium ions (Nd ions) in yttrium aluminum garnet (YAG matrix) is about 0.2, the axial doping concentration of the crystal naturally increases from the beginning to the end due to the "axial segregation" effect during the growth of the disposable charge, so as to form an uncontrollable concentration distribution, and it is difficult for the related art to actively grow a functional crystal having a predetermined concentration gradient, such as a uniform distribution or a specific graded distribution. Meanwhile, the growable length of the crystal is limited by the initial charge amount in the crucible, and in order to obtain a crystal with a longer size, a crucible with a larger volume must be used and a large amount of high-purity raw material must be charged at a time, which not only increases the raw material cost and equipment burden of single growth, but also affects the quality of the second half of the crystal due to the continuous downward movement of the melt interface. In the crystal growth process, the liquid level is continuously reduced, and the solid-liquid interface of the crystal growth is changed, so that the interface of the crystal growth is disordered, and the crystal quality is affected. Disclosure of Invention In order to overcome at least the above-mentioned drawbacks of the prior art, an object of the present application is to provide a concentration gradient crystal growth method, comprising: Acquiring preset crystal concentration change trend data; Acquiring weight data of a currently grown crystal obtained by adopting a Czochralski method; determining a real-time growth rate of the crystal based on the weight data; determining the real-time replenishment rate of each component raw material corresponding to the crystal based on the preset crystal concentration change trend data, the real-time growth rate and the chemical formula ratio of the generated crystal; controlling a valve of a feeding unit for feeding raw materials to the crucible assembly, and feeding each component raw material at the real-time feeding rate to obtain crystals with a preset crystal concentration variation trend, wherein the melt liquid level in the crucible assembly is always kept at the same height. In one possible embodiment, the crystals of the predetermined crystal concentration variation trend are crystals in which the concentration of the first component raw material gradually increases along the crystal axis direction of the crystals; The step of controlling the valve of the feeding unit for feeding the raw material to the crucible assembly to feed each component raw material at the real-time feeding rate so as to obtain crystals having a predetermined trend of variation in crystal concentration includes controlling the valve to feed each component raw material at the real-time feeding rate so as to obtain crystals in which the concentration of the first component raw material gradually increases in the direction of the crystal axis. In one possible embodiment, the crucible assembly comprises a first crucible and a second crucible, the first crucible and the second crucible being nested and in communication with each other, the first crucible being located inside the second crucible; the step of controlling the valve of the feeding unit for feeding the raw material to the crucible assembly to feed each component raw material at the real-time feeding rate so as to obtain crystals having a predetermined trend of variation in crystal concentration includes: and supplementing corresponding component raw materials into the second crucible at the real-time supplementing rate, wherein the component raw materials flow into the first crucible through the through hole of the first crucible. The application also provides a crystal growth method, which comprises the following steps: Acquiring weight data of a currently grown crystal obtained by adopting a Czochralski method; determining a real-time growth rate of the crystal based on the weight data; Determining the real-time replenishment rate of each component raw material corresponding to the crystal based on the real-time growth rate and the chemical formula ratio of the generated crystal; Controlling a valve of a feeding unit for feeding raw materials to the crucible assembly, and feeding each component raw material at the real-time feeding rate so as to make the concentration of each part of the crystal uniform, wherein the