^7fIn this paper soft molding technology are presented for QFN. The current practice of encapsulating QFN is to use some form of film-assisted molding. However, using such adhesive tape is not cost-effective, since each piece of tape should preferably cover an entire leadframe surface, the tape cannot be re-used and furthermore it is also not environmentally friendly. In this work we are proposing molding QFN still as a map or a matrix format but without the use of polyimide tape. Instead, a coat soft polymeric/elastomeric material would be an integral on the molding tool. The function of the soft material will acts as the mechanical seal just as the polyimide tape would to prevent epoxy resin bleeding to the back of expose leads and die pad of the QFN. Result of this new packaging method moldability performance show that there are no issues with regards to MBF, delamination, lead solderability, lead protrusion and package warpage.
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