An Improved Fault Transfer Table Based Fault Modeling Method in Etch Process of Semiconductor Wafer Manufacturing System

Fault model and detection in etch process is one of the key point problem in Semiconductor Wafer Fabrication System. A well developed fault modeling and detecting method in this process contributes greatly to the yield and Overall Equipment Effectiveness. The etch process has its unique characteristics like abundant variables, huge collections of data and nonlinearity in most batch processes; hence it poses difficulties to traditional modeling methods. In order to demonstrate the detail characteristic of faults in etch process, an improved fault transfer table based fault modeling method is proposed in this paper. The main idea of this method is to illustrate the indications, faults and their relationships in logical equations. The experimental results of an industrial example show that it has advantages such as simple expression and high capacity of information, and therefore is especially useful for the fault detection and diagnosis of semiconductor manufacturing.