喷淋孔结构流体动力学特性研究

Effect of Showerhead Hole Structure on Flow-Field in Large Sized Chemical Vapor Deposition Reactor

喷淋板通常用在化学气相沉积等真空腔室中,其流体动力学特性是决定真空腔室性能的关键因素之一。本文利用自主开发二维直接模拟Monte Carlo模拟程序对单个不同形状喷淋孔结构中性气体流场进行了数值仿真研究;讨论了七种不同单个喷淋孔结构的速度场、压力场和温度场分布情况。中性参考气体为氩气,固定入口压力200 Pa、温度300 K。结果表明,喷淋孔入口或出口形状影响腔室的工艺性能;而将喷淋孔入口和出口均设计成锥形,则腔室内流场分布较为理想。研究成果为喷淋板设计提供直接参考,同时对化工、热处理、光伏电池制造等领域中腔室部件的研发具有重要意义。

The flow-field,originated from the large-sized showerhead with an array of thousands of holes to supply gases for the plasma enhanced chemical vapor deposition（ PECVD） reactor dedicated to fabrication of integrated circuits on 400 - 450 mm Si wafers,was approximated,modeled and simulated with the self-developed 2-D direct simulation Monte Carlo（ DSMC） code. The influence of the gas flow conditions,including the seven-type inlet / outlet geometries of a hole,pressure at the inlet and temperature,on the distributions of the velocity,pressure and temperature in the reactor chamber,was investigated. The simulated results show that the geometries of the hole＇s inlet / outlet significantly affect the flow-field. To be specific,when it comes to satisfactory gas flow-field,the showerhead hole with inverse conical（ V-shaped） inlet and outlet outperforms all the other holes at 200 Pa and 300 K. We suggest that the simulated results be of some technological interest for design of large-sized PE CVD and CVD reactor.