Thin and large die assembly pick up process optimization by dynamic modeling

Abstract

This paper studies the traditional thin and large die pick up process by finite element simulation. A complicated transient dynamic model is developed to simulate the die pick up process by ANSYS/LS-DYNA. Multiple 3D contact pairs are set up between collet and die, die and tape, tape and die holder, tape and eject pins in simulation. The modeling of the adhesive de-bonding process is critical to the thin/large die crack. A de-bonding criterion for die surface and tape is studied to show the die separation process from tape. A transient dynamic process of die pick up from tape is simulated. Die tensile stress is recorded during the whole process. Parametric models with different die sizes, different collet dimensions, different eject pin dimensions, different tape materials are investigated. Through the simulation, we wish to understand better how the traditional die pick up process could impact the die stress and its reliability.