Virtual Metrology Algorithm for TFT-LCD Manufacturing Process
In TFT-LCD manufacturing process, virtual metrology (VM) model is often employed to predict products quality variables using sensor variables. However, modern industrial processes are usually equipped with a large number of sensors that provide process variables data such as pressure, temperature, spectroscopic signals, heat or power supplied, etc. So, how to design a validated VM model is the key problem. In this paper, a novel approach is presented to overcome the problem of high dimensionality and collinearity in the process variables data. Firstly, canonical correlation analysis is used to overcome the collinearity of the variables measured or quality variables. Moving time window is also considered to resolve the process uncertainty. For the purpose of reducing computation cost, a reliance index is developed to determine the frequency of models parameters updating. Superiority of the proposed model is also presented when it applied to an industrial sputtering process.
virtual metrology canonical correlation analysis moving time window reliance index
Bi-Qi Sheng Tian-Hong Pan
School of Electrical and Information Engineering, Jiangsu University, Zhenjiang 212013, China
国际会议
上海
英文
2196-2199
2011-07-26（万方平台首次上网日期，不代表论文的发表时间）