As we all know, in the same area, the circular and square product area with the same diameter or side length can be placed is different, and the general square can be put more, in other words, the square has a higher utilization rate of the effective space. So why wafer instead of crystal square? The square DIE, in a circular WAFER always produces a certain amount of space waste, so in the pursuit of the most profitable and efficient modern, such a configuration can continue to use the reason, the circle can stand out in various shapes, It’s worth thinking about.
First of all, because of the production process of silicon wafer, the silicon wafer is purified and then melted by single crystal direct drawing method and then cut into pieces. The pull method used in the single crystal direct drawing process is rotary pull. This pull method determines the cylindrical shape of the ingot, thus determining that the wafer is round
But if you look closely, you will find that the wafer is not a standard circle,there are flat grooves or V grooves, this step can help the subsequent process to determine the location of the WAFER, but also marked the single crystal growth metallography, convenient for the subsequent cutting and testing procedures. And the basic cutting is in the edge position, is a certain sense of resource reuse.