The use of Silicone RTV Rubber for Alpha Particle Protection on Silicon Integrated Circuits

Alpha particle sensitive static RAMs have been shielded from externally emitted radiation with a coating of silicone RTV (Room Temperature Vulcanizing) rubber. This material, which was determined to have an average alpha activity of .0010 cm-2hr-1 in the 2-8 Mev range is applied to chips in a hermetic package. The RTV rubber does not affect the sealing yield or reliability of the packages. Devices with this coating were operated error-free for 106 device hours.