Publications
Failure analysis for the dual input quad NAND gate CD4011 under dormant storage conditions
Several groups of plastic molded CD4011s were electrically tested as part of an Army dormant storage program. These parts had been in storage in missile containers for 4.5 years, and were electrically tested annually. Eight of the parts (out of 1200) failed the electrical tests and were subsequently analyzed to determine the cause of the failures. The root cause was found to be corrosion of the unpassivated Al bondpads. No significant attack of the passivated Al traces was found. Seven of the eight failures occurred in parts stored on a pre-position ship (the Jeb Stuart), suggesting a link between the external environment and observed corrosion.