By changing from a vitrified bond (VS, VS202, etc), which has been used for rough grinding on Z1-axis, to a resin bond BT100 (Photo 4), it is possible to lower damage and suppress edge chipping *1, which is a cause of wafer breakage.Furthermore, by employing aZ2-axis wheel with BK-09 bond, which supports a larger removal of Z1-axis grinding damage, it is …