Improvements and alternatives for ultra fine pitch encapsulation

Wire bond plastic ball grid array encapsulation processes, namely the glob top and the transfer molding, have rapidly evolved over the last few years in ultra fine pitch packaging. This paper presents the different alternatives that were studied for both processes in order to overcome the technical challenges of the new high density type packages. A comparative study of the different available glob top valves and pumps is presented as well as new transfer molding process improvements. It is shown that even if today both encapsulation processes have their own individual advantages and product niches, there is a need and a newly developed solution to merge them for future technology applications.