Methods of forming semiconductor dies with perimeter profiles for stacked die packages

A method of forming semiconductor dies with rabbeted regions, the method comprising:

• forming a first channel along a street from a backside of the wafer to an intermediate depth between the backside of the wafer and a front side of the wafer, wherein the first channel has a first sloped sidewall and a second sloped sidewall that converge toward each other from the backside toward the intermediate depth;
• and
• forming a second channel by laser cutting from the intermediate depth in the wafer toward the front side of the wafer along an interface region where the first and second sidewalls of the first channel meet thereby separating a set of first semiconductor dies along the first sidewall from a set of second semiconductor dies along the second sidewall, wherein the first sloped sidewall defines a rabbeted region at a side of the first semiconductor dies and the second sloped sidewall defines a rabbeted region at a side of the second semiconductor dies.