A method of forming stacked die devices includes attaching first semiconductor die onto a wafer to form a reconstituted wafer, and then bonding second semiconductor die onto the first semiconductor die to form a plurality of singulated stacked die devices on the wafer. A support tape is attached to a bottomside of the second semiconductor die. A dicing tape is attached to the wafer. The wafer is laser irradiated before or after attachment of the dicing tape at intended dicing lanes that align with gaps between the first semiconductor die to mechanically weaken the wafer at the intended dicing lanes, but not cut through the wafer. The dicing tape is pulled to cleave the wafer into a plurality of singulated portions to form a plurality of singulated stacked die devices attached to the singulated wafer portions by the dicing tape. The support tape is removed prior to cleaving.