X射线光刻掩模后烘过程的瞬态热分析  

Transient Thermal Analysis of X-ray Lithography Mask during Post-exposure baking

作　　者：王永坤[1] 余建祖[1] 余雷[1] 陈大鹏[2] 

机构地区：[1]北京航空航天大学,北京100083 [2]中国科学院微电子中心,北京100010

出　　处：《微细加工技术》2003年第2期34-39,共6页Microfabrication Technology

基　　金：国家自然科学基金资助项目(59976004)

摘　　要：X射线光刻掩模是下一代光刻技术(NGL)中的X射线光刻技术的关键技术难点。在电子束直写后的掩模后烘过程中,掩模表面的温度场分布及温升的均匀性是影响掩模关键尺寸(CD)控制的重要因素,如果控制不当,会造成掩模表面的光刻胶烘烤不均匀,使掩模吸收体CD分布变坏。针对电子束直写后X射线光刻掩模的后烘过程建立了热模型,并采用有限元技术进行了瞬态温度场的计算。计算结果表明:采用背面后烘方式,在达到稳态时出现高温区和低温区,最大温差为10.19℃,容易造成光刻胶局部烘烤过度,而采用正面后烘方式,掩模达到稳态的时间短,温度分布均匀,烘烤效果好。X-ray lithography, one of the next generational lithography (NGL) techniques, is of great concern, and the process of the mask is the most important part. The temperature distribution on the surface of the mask, during postexposure baking(PEB) of the X-ray mask after electron beam writing(EBW), is very important for controlling the mask CD. If the temperature isn't controlled well, it will lead to the non-uniform temperature distribution of the resist, which will induce the bad mask CD distribution. In this paper, the thermal model of the X-ray mask, during PEB process after EBW, has been set up and the transient thermal analysis has been given by using the finite element method. The numerical results indicate that if PEB is used in manner of post-baking the bottom surface, high temperature region and low temperature region appear when it gets steady and the maximum temperature difference is 10.19℃, which will quite likely make parts of the resist baked excessively. If PEB is used in manner of post-baking the top surface, it will take less time for the mask to get steady and the temperature distribution is uniform, and the baking effect is much better.

关 键 词：X射线光刻 掩模 后烘烤 有限元技术 瞬态温度场 

分 类 号：TN305.7[电子电信—物理电子学]