Rapid localization of IC open conductors using charge-induced voltage alteration (CIVA)

Charge-induced voltage alteration (CIVA) is a new scanning electron microscopy technique developed to localize open conductors, on both passivated and depassivated ICs. CIVA overcomes the limitations usually encountered in localizing open conductors. CIVA images are produced by monitoring the voltage fluctuations of a constant current power, supply as an electron beam is scanned over the IC surface. Contrast variations in the CIVA images are generated only from the electrically open portion of a conductor. Because of this high selectivity, CIVA facilitates localization of open interconnections on an entire IC in a single, unprocessed image. The equipment needed to implement CIVA and examples of applying the technique to several failed CMOS ICs are described. Possible irradiation effects and methods to minimize them are also discussed.<>