Growth method for preparing sapphire single crystal with Kyropoulos method

Abstract

The invention provides a growth method for preparing a sapphire single crystal with a Kyropoulos method. The growth method mainly comprises the following control phases: a shouldering phase, an equal-diameter growth phase and an ending phase, wherein the shouldering phase is performed after seeding ending and comprises an initial shouldering stage and a later shouldering stage, the cooling speed is controlled by adjusting the voltage and matched with the crystal pulling speed to achieve stable growth at the initial shouldering stage, the crystal grows to about 1.5 kg after 20-25 h growth, and the crystal enters the later shouldering stage, the voltage adjusting quantity is smaller than that in the initial shouldering stage, the pulling speed is increased at the later shouldering stage and cooling is performed gradually, growth is performed for 45-52 h, and the crystal grows to about 4 kg and enters the equal-diameter growth phase; the crystal pulling speed is decreased at the equal-diameter growth phase, cooling is accelerated simultaneously, growth is performed for 75 h, and the crystal grows to about 28 kg-32 kg and enters the ending phase; and the cooling speed is further decreased and fast pulling is performed at the ending phase, and automatic draw-off is achieved. The growth method for preparing the sapphire single crystal with the Kyropoulos method can solve the problem that more bubbles exist in the sapphire single crystal grown with the conventional Kyropoulos method.

Description

1. Technical field [0001] The invention relates to a growth process for sapphire single crystal growth, in particular to a growth process for preparing high-quality sapphire crystals by a Kyropoulos method. 2. Background technology [0002] Sapphire single crystal has a unique lattice structure, excellent mechanical properties, and good thermal properties. It can work under harsh conditions close to 2000 ° C. It is known for its high strength, high hardness, erosion resistance, and excellent comprehensive properties. Widely used in science and technology, space vehicles, windows of high-intensity lasers, national defense and civil industry, and many other fields of electronic technology, it has also become the preferred material in the current LED market. [0003] With the continuous development of technology in related application fields and the continuous expansion of industrial scale, especially the demand for sapphire crystals in LED lighting is increasing, not only the ...

AI Technical Summary

Problems solved by technology

[0006] The purpose of the present invention is to provide a method that can solve the problem that there are many bubbles inside the sapphire single crystal grown by the traditional kyropoulos method, conduct an in-depth analysis on the causes of the bubbles, and conduct an in-depth analysis of the key parameters in the sapphire single crystal growth process prepared by the kyropoulos method. Readjusted to form a growth method for preparing sapphire single crystals by Kyropoulos that can solve the problems of sapphire crystals with many bubbles, large thermal stress, easy crucible drop, and cracking

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