2-Step algorithm for automatic alignment in wafer dicing process

摘要

In this study, automatic alignment algorithm was developed for wafer dicing. Dual inspection method was applied for wafer alignment. The algorithm was derived from inspection data and geometric relations on machine coordinate. The algorithm calculated compensation value which minimized x, y, θ errors. Control strategy was designed according to characteristics of each axis. In experiment, standard position was defined with golden device. When working device was put on stable, it was aligned and moved by compensation value. Alignment error were inspected to check accuracy and precision of the algorithm. Average error was sub-pixel level for y axis on vision coordinate.