Understanding the use of silicone gels for non-hermetic plastic packaging

High-performance silicone gel has been shown to possess excellent electrical and physical properties for VLSI packaging. With their intrinsic low modulus and soft gel-like nature, silicone gels have become very effective encapsulants for larger, high-I/O, wire-bonded VLSI chips. Recent studies indicate that adequate IC chip surface protection with high-performance silicon gels in plastic packaging could possibly replace conventional ceramic hermetic packaging. Some potential IC encapsulants are reviewed, focusing on the silicone gel, its chemistry, and its use as a VLSI device encapsulant for single- and multichip application. Testing of the gel is discussed, and temperature-humidity-bias test results are reported. Military applications of the gel are considered