Wafer chip grinding method

The present invention relates to a wafer chip grinding method and, more particularly, to the wafer chip grinding method capable of grinding each chip by using a grinding device after separating a wafer chip to reduce the thickness of the chip. The wafer chip grinding method according to the present invention comprises the steps of: 1) attaching a first back grinding tape to the opposite side of a wafer pattern and cutting the wafer and a part of the first back grinding tape; 2) vertically inverting the cut wafer and attaching a second back grinding tape and a third back grinding tape to the wafer pattern; 3) removing the first back grinding tape from the inverted wafer; 4) cutting the second back grinding tape and a part of the third back grinding tape along the cut part of the wafer and separating the chip and the second back grinding tape from the cut wafer; 5) grinding the opposite side of the pattern of the separated chip; and 6) removing the second back grinding tape from the ground chip. [Reference numerals] (AA) Come up from the previous proces;(BB) Move onto the post-process;(S310) Step of cutting wafers and a first back side tape;(S320) Step of vertically inverting the cut wafer and attaching a second back grinding tape and a third back grinding tape to the wafer pattern;(S330) Step of removing the first back grinding ta;(S340) Step of cutting the second back grinding tape and a part of the third back grinding tape and separating the chi;(S350) Step of grinding a chip;(S360) Step of removing the second back grinding tape