Locating the Centre Line of Paddle Vats for Cutting Wafer Images by Using Binary Segmentation

In the research of the self-aligned dicing technology, due to tens of thousands of types of wafer image samples, there are diverse types of street in wafer image. In order to properly identify the paddle vat in the street and get center line of the paddle vat for cutting by using binary segmentation, it's a crucial step for binarization of wafer images. To take into account the diversity of the wafer images, it is quite difficult to find a good threshold. In this paper, we propose a binarization approach based on the density histogram to locate the center line of paddle vat of the wafer image. The histogram of a wafer image is smoothed by using a quadratic exponential function and then an appropriate threshold is calculated. The experiments show that the new method is very effective for the wafer image processing.