Primary flat is perpendicular to X' axis with accuracy +/-15 min Yxlt/48.5°/26.6°
No chipping inside the working area and on the primary flat. Chipping can be accepted outside the working area if the width is less than 0.5 mm, and the cumulative length is less than 5 mm.
No dimples, cracks, unpolished areas, ontaminants in working area under x50 magnification. Scratches visible at x50 magnification are allowed in working area if their quantity is lower than 3 on one wafer and less than 20 in a lot of one hundred wafers.