By changing PDC cutter diamond end face from a plane to a curved surface, the "scraping" is then changed into "ploughing". The "spinal surface" on the end face points to the rock face along its length with the flank faces on both sides leaning backward to a certain angle, like a plough surface. It helps quick displacement of rock chips and reduces cutter advancing resistance. Also, drill teeth's efficiency in rock breaking and bit's drilling speed are greatly improved. Arch-like structure notably improves cutter overall impact resistance.