Method for growing indium phosphide single crystal by VGF method

Abstract

The invention belongs to the field of preparation of indium phosphide single crystals, and particularly discloses a method for growing indium phosphide single crystal by a VGF method. The method comprises the steps of putting raw materials into a crucible and assembling a single crystal growth furnace by adopting the VGF method, and carrying out high-temperature annealing treatment; raising the temperature of the melt, and setting a heating target value in a heating control program for heating and pressurizing; carrying out seed melting growth, setting a growth temperature, when the melting length of the seed crystal reaches 10-15mm and the rotating shoulder growth is carried out, enabling the position of the crucible to begin to descend with the descending speed being not greater than 2.5 mm / h, and automatically stopping the descending of the crucible position after the growth is finished; and conducting cooling and annealing, specifically, automatically conducting cooling and annealing after growth is finished, emptying air pressure in the furnace after the temperature is reduced to 350 DEG C, opening a furnace door after the temperature in the furnace is reduced to about 150 DEG C, and obtaining the single crystal. According to the invention, the pulling speed method is added, so that the thermal field of the indium phosphide single crystal in the growth process is more uniform, vertical orientation crystallization is more stable, more indium phosphide single crystals grow, and the qualified rate of the crystal is higher.

Description

technical field [0001] The invention belongs to the field of indium phosphide single crystal preparation, and in particular relates to a method for growing indium phosphide single crystal by a VGF method. Background technique [0002] Indium phosphide single crystal is an important second-generation compound Ⅲ-Ⅴ semiconductor crystal after germanium crystal and gallium arsenide crystal. It is mainly used in the fields of optoelectronic technology, microwave technology and space satellite communication. The preparation process of high-quality indium phosphide single crystal materials has higher requirements and is more difficult. Because indium phosphide single crystal whiskers can only be prepared under high temperature and high pressure, and the stacking fault energy of indium phosphide is low, it is easy to produce twins, so large-sized, high-quality indium phosphide single crystals are difficult to prepare. The growth methods of indium phosphide single crystal mainly inc...

AI Technical Summary

Problems solved by technology

However, the pass rate of indium phosphide single crystal obtained by traditional VGF growth is low, and the diameter is mainly 2" and a small amount of 3", which is difficult to meet the needs of the application market.

Although the indium phosphide single crystal grown by LEC has a high crystallization rate, it is affected by high dislocations, uneven distribution of carrier concentration and electron mobility, which indirectly affects the application life and cost of high-power microwave devices.

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