Adoption of single-sided adhesive tape to improve thermal-cycling reliability in plastically-encapsulated semiconductor devices

A more advanced tape structure was designed to improve the thermal-cycling reliability of the semiconductor devices packaged using the LOC die attach technique. The thermal-cycling test indicates that the replacement of the conventional DSAT by the advanced SSAT is very effective for suppressing the propagation of the pre-existing cracks induced at the device edge prior to the reliability test. This is because the complete elimination of the lower-sided adhesive layer can reduce the thermal-cycling induced stress level on the device pattern. Herein, the removal of the lower-sided adhesive layer indicates its substitution with the base layer with many through-holes, which will be infiltrated by the single-sided adhesive material due to capillary action. Thus, if a base layer having a value of CTE close to silicon is adopted, the thermal-cycling reliability of corresponding semiconductor devices will be maximized due to much reduced thermal displacement-induced stress level. Consequently, the present work suggests that the use of a single-sided adhesive tape might offer greater reliability range for the structural modification or material selection of the active pattern in plastic packages.