Abstract：Wafer cooling/heating by gas flow along the backside of the wafer is a key part of the plasma-etching process. The rarefied gas heat transfer across the gap between the wafer and the electrostatic chuck is modeled in this article with an analytical equation developed for the entire pressure range whose predictions are verified by direct simulation Monte Carlo results. The model is then used to investigate the effects of the gas pressure, gap size, accommodation coefficient and gas temperature on the heat transfer coefficient. The gap size and gas temperature have little influence, so the etching temperature and the surface profiles like the height have little effect on the heat transfer between the wafer and the electrostatic chuck. However, the gas pressure and the accommodation coefficient significantly impact the heat transfer coefficient. Therefore, changes in the gas pressure during the etching process will significantly affect the heat transfer between the wafer and the electrostatic chuck.
孙钰淳, 程嘉, 路益嘉, 侯悦民, 季林红. 静电卡盘与晶圆之间稀薄气体传热的影响因素[J]. 清华大学学报（自然科学版）, 2015, 55(7): 756-760.
SUN Yuchun, CHENG Jia, LU Yijia, HOU Yuemin, JI Linhong. Factors influcing rarefied gas heat transfer between a wafer and an electrostatic chuck. Journal of Tsinghua University(Science and Technology), 2015, 55(7): 756-760.
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