【摘要】 根据现有氮化镓(GaN)金属有机物化学气相淀积(Metalorganic Chemical Vapor Deposition)生长动力学理论,结合具体的MOCVD反应腔体的构造,用计算流体力学和动力学蒙特卡罗方法对GaN MOCVD生长过程中的生长速率和表面形貌演变进行了计算机模拟。结果表明,在950~1350 K的温度范围内反应气体充分热分解,是适合GaN外延生长的温度区间;温度低于950 K,反应气体未能充分地分解,导致较低的生长速率;而温度高于1350 K则Ga组分的脱附现象开始变得严重,从而抑制GaN的生长速率。另一方面,较高的V/III也会抑制GaN的生长速率。生长过程中表面形貌随时间的演变结果显示,GaN薄膜在高温下(1073~1473 K)为2D层状生长,在1373 K的温度下生长的GaN薄膜表面最为平整。更多还原

【Abstract】 With the known growth mechanism of GaN grown by metalorganic chemical vapor deposition(MOCVD),a computational study of GaN MOCVD was performed by the method of Computational Fluid Dynamics(CFD) and Kinetic Monte Carlo(KMC).The construction of 2D reactor used in the simulation was referred to the MOCVD system in the laboratory.The calculated results suggest that the gas precursors could be completely decomposed between 950 and 1350 K and the GaN should grow in this temperature range.The growth rate would decrease below 950 K owing to the partially decomposition of precursors.And the growth rate above 1350 K would do the same owing to desorption of Ga species. On the other hand,high V/III ratio could bring low growth rate.The morphological evolution during growth showed that GaN film grew in a layer-by-layer mode at 1073～1473 K and the film structure grown at 1373 K was the smoothest one.更多还原