METHOD FOR DIVIDING WAFER

摘要

PROBLEM TO BE SOLVED: To provide a method for dividing a wafer which enables the increase in the flexural strength of a chip.SOLUTION: A method for dividing a wafer comprises: a front-side V-groove formation step in which plasma etching is performed on the wafer (11), thereby forming a front-side V-groove (53) having a V-shape in section along a scheduled dividing line (17) in a front-side surface (11a) of the wafer; a backside V-groove formation step in which plasma etching is performed, thereby forming a backside V-groove(55) having a V shape in section in a region corresponding to the scheduled dividing line in a backside surface (11b) of the wafer; and a thin groove formation step in which after the execution of the front-side V-groove formation step and the backside V-groove formation step, plasma etching is performed on a bottom of the V-groove in the front-side surface, or a bottom of the V-groove in the backside surface, thereby forming a thin groove (59) which communicates the bottom of the front-side V-groove and the bottom of the backside V-groove to each other, and has a width narrower than the maximum width of the front-side V-groove and the backside V-groove.