光学 精密工程, 2013, 21 (11): 2829, 网络出版: 2014-01-09
热扰动条件下投影物镜温度响应的高精度建模
High accuracy temperature response modeling of projection lens under thermal disturbance
投影物镜 热扰动 伪随机信号 系统辨识 温度控制 projection lens thermed disturbance pseudo-random signal system identification temperature control
摘要
针对投影物镜温度控制系统具有多重扰、多时滞和时间常数较大等问题, 搭建了投影物镜温控实验平台; 研究了实验平台的结构、激励信号设计、数据预处理方法和建模算法, 建立了超高精度温度响应模型。首先, 考虑光刻机对震动和洁净度的严格要求, 设计了远距离串级水冷控制系统; 进行了物镜温度的阶跃响应实验, 采用两点法建立了物镜的温度响应传递函数(粗建模)。然后, 根据获得的物镜阶跃响应传递函数, 设计二位式伪随机辨识输入信号的参数, 并采用分段线性化方法对输入输出数据进行预处理。最后, 设计迭代最小二乘算法,辨识得到物镜的ARMAX温度响应模型(精建模)。基于该模型的物镜温控实验结果表明:在环境温度波动幅值达0.6 ℃并加入3 W的热扰动条件下, 物镜温度稳态误差控制在±0.001 ℃以内, 满足光刻机对投影物镜的超高精度温度控制要求。
Abstract
In consideration of the repetitive disturbance, time lag and a larger time constant in a temperature control system for the projection lens, a temperature control experimental platform of projection lens was built. The structures, data preprocessing method and modeling algorithm for the experimental platform were researched, and a high precision temperature response model was established. Firstly, Taking into account the request of a lithographic machine for stringent vibration and cleanliness, the long-distance range cascade water cooling control system was designed. Then, the step response experiment of projection lens on the temperature was carried on, and the temperature response transfer function of projection lens was established with the two-point method(coarse model). Furthermore, pseudo random input signal was designed on the basis of the transfer function, and the input and output data were preprocessed by using the piecewise linear method. Finally, the iteration least square algorithm was designed to obtain the ARMAX temperature response model of projection lens. The temperature control experiment based on the model show that the temperature stability of the projection lens achieves ±0.001 ℃ in environment temperature with a fluctuation amplitudes up to 0.6 ℃ and thermal disturbance of 3 W, which meets the requirements of projection lens of lithography for ultra-high-precision temperature control.
秦硕, 巩岩, 于新峰, 袁文全, 彭海峰, 杨怀江. 热扰动条件下投影物镜温度响应的高精度建模[J]. 光学 精密工程, 2013, 21(11): 2829. QIN Shuo, GONG Yan, YU Xin-feng, YUAN Wen-quan, PENG Hai-feng, YANG Huai-jiang. High accuracy temperature response modeling of projection lens under thermal disturbance[J]. Optics and Precision Engineering, 2013, 21(11): 2829.