Patent ID: 8415232

Claim:
A wafer dividing method for dividing a wafer into a plurality of individual devices along a plurality of division lines formed on the front side of said wafer, wherein said devices are respectively formed in a plurality of regions partitioned by said division lines, said wafer dividing method comprising: a protective member providing step of providing a protective member on the front side of said wafer; a back grinding step of grinding the back side of said wafer to reduce the thickness of said wafer to a predetermined thickness; a modified layer forming step of applying a laser beam having a transmission wavelength to said wafer from the back side of said wafer along said division lines in the condition where the focal point of said laser beam is set inside said wafer at a position corresponding to each division line, thereby forming a plurality of modified layers inside said wafer along said division lines at such a depth not reaching a finished thickness of each device; a wafer dividing step of dividing said wafer along said modified layers into said individual devices; a modified layer removing step of grinding the back side of said wafer divided into said individual devices to thereby remove said modified layers and reduce the thickness of each device to said finished thickness; a frame providing step of preparing an annular frame having a circular opening, attaching a dicing tape at its outer circumferential portion to said annular frame so as to close said circular opening, attaching a die bonding film to said dicing tape in said circular opening of said annular frame, and attaching the back side of said wafer to said die bonding film; a protective member removing step of removing said protective member from the front side of said wafer; and a die bonding film dividing step of expanding said dicing tape to increase the spacing between any adjacent ones of said individual devices, thereby dividing said die bonding film along the boundaries of said individual devices.