Silicone wafers are unbelievably fragile(I've worked with them alot) - think the ruggedness of thin dry leaves in the fall. The slightest scratch is huge problem, as the dopant can be quite shallow on one side. A process which can remove integrated components from them without breaking them is actually quite impressive from that regard - although it probably is just a buffing machine of some sort, it would need to be very delicate.