Process method capable of effectively overcoming Kyropoulos-method crystal cracking

Abstract

The invention discloses a process method capable of effectively overcoming Kyropoulos-method crystal cracking. The process method specifically comprises a process method for preventing the large area of the bottom of a crystal from being stuck to a crucible in a crystal growth process and releasing the crystal from the crucible after the growth is ended. By controlling a pulling speed and a cooling speed at the later period of equal-diameter growth, the growth speed of the crystal becomes slow; the crystal is released from a wall of the crucible through regulating a voltage value and manipulating a pulling rod. With the adoption of the process method disclosed by the invention, a condition that the large area of the bottom of the growing crystal is stuck to the crucible can be effectively prevented, and the diameter consistency of the crystal is good; in a cooling process, the crystal is separated from the wall of the crucible, so that the heat stress of the crystal is reduced, the probability of the crystal cracking is greatly reduced, and the yield and the sampling rate of the crystal are improved; the growth period can be easily shortened and the production cost is reduced.

Description

technical field [0001] The invention relates to the field of kyropoulos crystal growth, in particular to a method for effectively solving crystal cracking during the kyropoulos sapphire crystal growth process. Background technique [0002] Sapphire crystal (commonly known as corundum) has excellent properties such as high melting point, high hardness, good thermal conductivity, high light transmission from vacuum, ultraviolet, visible, and from near-infrared to mid-infrared. In addition, sapphire crystal has high temperature resistance Solubility, good chemical stability, excellent laser matrix material, window material for various optical components, infrared military devices and high-intensity lasers, widely used in the substrate materials of blue light semiconductor diodes LED and diode LD, almost all Substrate field. [0003] At present, the growth methods of sapphire mainly include pulling method (CZ), guided mode method (EFG), kyropoulos method (KY), heat exchange met...

AI Technical Summary

Problems solved by technology

Ideally, the crystal should not be in contact with the crucible during the growth process, but due to the slightly convex shape of the solid-liquid interface and the large temperature gradient at the bottom of the crucible, the growth rate of the crystal is too fast in the later stage of equal diameter growth and it is difficult to control, and the bottom of the crystal is easy to crucible. Wall phase adhesion forms a large-area sticky crucible, which leads to excessive thermal stress of the crystal during the cooling process, resulting in cracking, greatly reducing the yield and material yield of the crystal, and prolonging the growth cycle and increasing production costs.