Die Traceability Using Backside Mask Layers

A method for making a chip device comprising:

• applying, patterning, and developing photoresist over a backside of a wafer comprising a plurality of chips to form a patterned backside photoresist mask with a plurality of unique patterned mask openings;
• using the patterned backside photoresist mask to form, on the backside of the wafer, a unique die mark identifier pattern corresponding to the plurality of unique patterned mask openings, where the unique die mark identifier pattern comprises a first unique pattern for a first set of one or more chips and a second unique pattern for a second set of one or more chips;
• removing the patterned backside photoresist mask from the backside of the wafer to leave the unique die mark identifier pattern in place;
• and
• singulating the wafer to form a plurality of chip devices.

An integrated circuit device, comprising:

• a semiconductor substrate comprising a backside surface and an opposing frontside surface on which integrated circuit device features are formed;
• and
• a patterned unique die mark identifier formed on the backside surface of the semiconductor surface;
• where the patterned unique die mark identifier comprises an alphanumeric label, bar coding label, binary pattern, or die-specific mark which is unique for the integrated circuit device and which does not include photoresist.