扩散炉管气体流动分析和流量计算数学模型

Diffusion Furnace Gas Flow Analysis and Mathematics Model

环境温度气体通过进气管进入高温扩散炉管后迅速膨胀,气体流量和流速均数倍增加;气体射流在炉尾形成的紊流区延伸到工艺恒温区范围,导致靠近炉尾恒温区的气体流动不稳定。通过放置挡板或挡片的方式可以减轻炉尾紊流区对恒温区Si片工艺的影响。根据扩散炉管内气体的流动状态和气体动力学有关参数和计算方法,推导出计算气体流量的数学模型公式,只需利用扩散炉管的基本参数就可以计算出需要通入炉管的环境温度气体流量,减少凭经验判定气体流量参数的盲目性,减少不必要的气体材料消耗。

Ambient temperature gas passing into high temperature diffusion furnace through inlet pipe expant rapidly,and gas flow and flow rate are increased many times.The turbulent flow formed by gas jet-flow is extended to constant-temperature area,leading to gas flow instability in a constant-temperature area near the furnace end.Influence of turbulent flow to wafer process in constant-temperature area was decreased by placing a buffer or baffling wafers near the furnace end.Based on parameters and calculation methods of diffusion furnace gas fluid and gas dynamics,mathematics model formula was derived to calculate gas flow.Ambient temperature gas flow passing into the furnace can be calculated using basic parameters of diffusion furnace.Thus,blind judgment of gas flow and unnecessary gas consumption are avoided.