Matrix form of automatic alignment algorithm in 2D space

Automatic alignment techniques in wafer processing have been developed on the basis of experiment. They were derived from case-by-case idea, so they were not easy to be applied to other cases. This fact came from the lack of generality of the related researches. This paper proposed a key to make a general model for automatic alignment in 2D space. The algorithm was developed under assumption of precise positioning system with vision inspection. To describe motion of machine, modified rigid body transformation was proposed. It contained x, y, /spl theta/ alignment in 2D space. The suggested formula had a simple matrix form, which could be connected to state-space equation. Current alignment models could be built with this form. Final equation also solved direction changes in the system. Experiment was done on the dicing machine, and alignment values were obtained with rule-based algorithm. The result from matrix form was compared and verified with this experiment.