The evaluation of the reliability of organic coatings for integrated circuits

Integrated circuits mounted on ceramic substrates must be protected from moisture and from mechanical damage by an encapsulation system which should have the same long term stability as the device itself. The procedures used for evaluating device stability - high temperature and high humidity exposure to time of median failure - have been used to evaluate the ability of coatings to protect devices and substrates from leakage currents due to water adsorption. Most of the data has been obtained on silicone resins and rubbers that were selected as the best materials for humidity protection after an initial evaluation of a number of coatings.