MOCVD生长GaN的数值模拟和喷淋式反应室结构优化

MOCVD Process Numerical Simulation of GaN and Geometrical Optimization of the Showerhead Reactor

对喷淋式MOCVD反应室内的输运过程及GaN的材料生长进行了二维数值模拟研究。在模拟计算中,分别改变反应腔体几何形状、顶盘入气小孔分布方式等条件,得到反应室内流场、热场及薄膜沉积速率的相应变化。根据对模拟结果的分析,发现基座上方没有涡旋的平直流场及较大的温度梯度有利于提高沉积速率及其均匀性,通过旋转基座可以实现上述结果;腔体内壁的圆弧化、小口径的顶盘入气孔等反应室结构优化方式有助于材料生长的均匀性。

Two-dimensional numerical study on transport phenomena and growth of GaN in the showerhead MOCVD reactor were conducted.By varying the reactor geometry and distribution mode of inlet,the corresponding flow,thermal fields and film deposition rate inside the reactor were calculated.It is found that flat flow lines without swirl and thin temperature gradient above the susceptor are crucial to improve the rate and uniformity of the film deposition by susceptor rotation.The circular geometrical reactor and small diameter inlet holes can be employed to improve the uniformity of the film growth.