A Current Pulse Screening Test for Metal Step Coverage.

The project was undertaken to determine if single-shot electrical pulses of short duration ZAP Testing can be employed as an effective screening process for metallization defects which would significantly reduce current carrying capacity. The type of defect which is of primary concern at present is inadequate metal coverage over irregularities on a wafer surface - especially over a step cut into an oxide layer. Metal coverage can be defined as the ratio of the minimum metal thickness over the surface irregularity to the thickness of metal on the adjoining flat surface.