Ultrathin Die Pick-Up for 3D Chip Stacking

Ultrathin die pick-up is studied for 3D IC applications. Failure modes are identified as follows: 1) no pick-up due to insufficient peeling; 2) die crack created by ejector; 3) neighboring die crack due to ejector push-up. Optimal dicing tape is selected along with pick-up process tuning. By using optimal dicing tape, pick-up process window is identified for 20 and 30 mu m thickness Si die with 8x8 and 12x12 mm die size. The failure modes of "die crack created by ejector" and "neighboring die crack" occur when push height is large and/or pickp-up time is short. The failure mode of "no pick-up" occurs at insufficient push height. Finally, pick-up conditions with 100% yield are identified with <= 1 sec pick-up time.