Dynamic simulation of die pickup from wafer tape by a multi-disc ejector using peel-energy to peel-velocity coupling

Abstract

A 2D simulation of thin die peeling from wafer tape is presented for a Multi Disc ejection system. The simulation models the dynamics of peeling, and visualizes time-dependency of peel front propagation and target die stress. It is based on a series of static snapshots, stringed together like a movie. A coupling of peel energy and peel velocity is defined. This allows to calculate the geometry of the actual snapshot by the peel energy of the preceding one. As a result, experimental data of a peel process can be verified. It is shown, why an increase in disc velocity leads to a slow-down of peel front propagation, and thus to a pickup failure.