| dc.description.abstract | Aluminum nitride is a wide band gap (6.2 ev) semiconductor material. Aluminum nitride is high thermal conductivity and widely used in light-emitting diode materials. In the process of aluminum nitride crystals, the Physical Vapor Transport (PVT) method is commercially used. The sublimation is used to sublimate the aluminum nitride powder into aluminum gas and nitrogen, and then it is transported by the difference of saturated vapor pressure. In order to achieve the quality required by the industry, the high-quality structure of aluminum nitride is crucial, and the most important factor affecting the quality is the growth temperature distribution.
The experiment is widely used in the previous researches, but the numerical simulation rarely used. Therefore, the crystal growth furnace including the insulation layer thickness, crucible lid thickness, and coil position, etc., is modified to study the influence of these factors on the growth temperature distribution.
The results show that when the crucible lid is thicker and the top space of the air inlet is maintained, the temperature gradient of seed becomes more uniform and difficult to dissipate because of the increased thermal resistance. When the insulation layer is thicker and high resistance, it will lead the temperature more uniform and high degree. When changing the position of the coil, the high magnetic flux position will lead a high heat source, and the center of the coil is the largest part. We can control the temperature field in the certain area of the crucible by this way. | en_US |