Single crystal silicon ingots are characterized by the orientation of their silicon crystals. Before the ingot is cut into wafers, one or two "flats" are ground into the diameter of the ingot to mark this orientation.

After characterization, the ingot is sliced  into individual wafers with a precision "ID Saw," so named because the cutting edge of the blade is on the inside. This type of saw is used because the blade has less "kerf" and produces a more precise and controllable cut and a flatter wafer.