This paper reports on the use of an emerging process technique for curing of polymer encapsulants as used in the electronic packaging industry. Previous work performed in the area of materials processing has demonstrated the usefulness of sweeping operating frequencies in order to achieve high levels of electric field uniformity and process control. The use of controlled variable frequency microwave energy has been evaluated as a process technique compatible with electronic packaging requirements. The heating of a series of integrated circuits (ICs) and their subsequent characterization was performed. IC integrity was investigated using X‐Ray, Acoustic Microscopy, Decapsulation and Bond Pull. Processing of liquid encapsulants, underfills and glob‐tops, used in Flip Chip and Chip On Board (COB) applications, was performed. Differential Scanning Calorimetry was used to study cure extent. Further studies show that variable frequency microwave processing leads to fast curing of encapsulants. A reduction in cycle times from 15 to 20 times over conventional curing has been observed. Also, results have showed a reduction in the stresses induced by mismatches in coefficient of thermal expansion.
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