A low-cost method for preparing gallium nitride crystals

Abstract

The present invention belongs to the field of semiconductor materials, and in particular relates to a low-cost method for preparing a gallium nitride crystal. According to the method, a high temperature resistant inorganic mineral with a layered structure is used as a template, a surfactant and a metal complexing agent are used for modifying the inorganic layered mineral, and gallium ions are adsorbed uniformly in the layered structure of the inorganic mineral; the layered structure of the inorganic mineral is used as a gallium source precursor, and is placed in a quartz crucible to put into a tube furnace for reaction for 1-3h under a 250-400 DEG C air atmosphere, tube furnace temperature is raised to 800-1000 DEG C, ammonia gas is introduced into the tube furnace for reaction for 1-2h, an obtained crude product is washed with an acid to obtain a large-size pale yellow gallium nitride crystal in a regular crystal form. A confinement space between the layers of the inorganic mineral is used, so that the gallium nitride crystal grows along a gap of the layered structure, the layered structure confinement space has a certain thermal insulation effect, and can reduce the reaction temperature and improve reaction time. The cost is low, and the method is suitable for mass production.

Description

technical field [0001] The invention belongs to the field of inorganic compound semiconductor materials, in particular to a method for preparing gallium nitride crystals at low cost. Background technique [0002] Gallium nitride (GaN)-based semiconductor materials are new semiconductor materials for the development of optoelectronic devices and microelectronic devices. Together with semiconductor materials such as silicon carbide (SiC) and diamond, they are known as the third-generation semiconductor materials. GaN material belongs to the direct transition type wide bandgap semiconductor material. The wide direct bandgap of GaN is 3.4eV. It has excellent properties such as high electron drift saturation speed, small dielectric coefficient, good thermal conductivity and high radiation resistance, so it is a good semiconductor. It is an ideal material for making light-emitting diodes (LEDs), laser diodes (LDs) and high-temperature high-power integrated circuits. GaN also has ...

AI Technical Summary

Problems solved by technology

At present, the preparation of GaN materials can be obtained by chemical vapor deposition, pulsed laser deposition, sol-gel method, molecular beam epitaxy, etc. For example, Chinese Patent Publication No. CN101774552A discloses a preparation method of GaN nanocrystals. First, Ga 2 o 3 Added to concentrated nitric acid and heated by microwave hydrothermal heating to form GaO 2 H nanorods, then the GaO 2 The H nanorod powder is placed in a tube furnace and reacted with ammonia gas at high temperature to obtain light yellow GaN nanocrystals. The advantages are that the raw materials are relatively cheap and the process operation is simple. However, due to the need to use concentrated nitric acid in the preparation process, the safety factor is low. Moreover, the precursor nanorods are not conducive to the growth of gallium nitride crystals, and it is not easy to obtain high-quality gallium nitride crystals

[0004] Chinese Patent Publication No. CN1944268 discloses a method for preparing gallium nitride nanocrystals by a sol-gel method. First, a gallium oxide / amorphous carbon mixture is prepared by a sol-gel method, that is, gallium nitrate is dissolved in concentrated nitric acid, and citric acid is added. After heating and stirring for 2 hours, it becomes a transparent gel after cooling, put it into a ceramic tube after drying, and react with ammonia gas at a temperature of 850-950°C to obtain light yellow GaN nanocrystals. This method can produce a large number of particle diameters smaller than or equal to Bohr excitons However, due to the need to use concentrated nitric acid in the preparation process, the safety factor is low, and the area of ​​the prepared nanocrystals is small, which affects the performance of gallium nitride crystals and is not conducive to large-scale production

[0005] However, the crystal growth rate prepared by the sol-gel method in the above method is low, the cycle is long, and the shape of the generated crystal is irregular, which affects the quality of the gallium nitride nanocrystal, and it is not easy to popularize the large-scale industrial production of the gallium nitride nanocrystal; To prepare gallium nitride crystals by chemical deposition, it is necessary to find a suitable substrate material. The substrate materials currently used are expensive and have lattice defects, which reduce the quality of the crystal.