紫外光固化中阻蚀胶薄膜应力分析及成膜控制

Stress Analysis and Filming Control of Resist on Ultraviolet-Curable Resist

针对压印光刻工艺实现图章保真复型对阻蚀胶薄膜的均匀度和应力分布的要求,对匀胶过程中的时间、转速和加速度等参数进行了分析,并采用基片曲率法的Stoney公式及其近似计算公式,对不同参数环境下的薄膜应力及应力梯度分布作了计算分析.通过对比几组试验参数的应力分析结果,验证了薄膜应力的大小和应力梯度的分布主要与匀胶时间和速度有关,而与加速度的关系较小.因此,当选用匀胶转速为5 000 r/min、时间为30 s时,薄膜应力分布最优,成膜质量最佳,能够满足压印光刻工艺中300 nm级图型的保真复型需求.

To achieve high accuracy of pattern transferring in ultraviolet （UV）-based imprint lithography （IL）, three parameters in spin coating processes, angular velocity, angular acceleration and processing period are analyzed for the thin film uniformity and stress gradient. Stoney formula and the corresponding approximate deducing with substrate curvature method are adopted to evaluate the film stress in several processes. The results show that the stress state of UV-curable resist film mainly depends upon the period and angular velocity. And when the spin coating angular velocity is 5 000 r/min and the period is 30 s, the film stress state gets the optimum to meet the requirement of 300 nm pattern transferring in IL processes.