Barrel-plating quad flat no-lead (QFN) packaging structures and method for manufacturing the same

摘要

A barrel-plating quad flat no-lead (QFN) package structure and a method for manufacturing the same. The method includes: providing a metal substrate for a plurality of QFN components; forming a first photoresist film on a top surface of the substrate; forming a plating pattern in the first photoresist film; forming a first metal layer containing a plurality of inner leads; etching the substrate from the back surface of the substrate to form a plurality of I/O pads; filling sealant in the etched areas; attaching at least one die in a predetermined region on the top surface of the substrate; connecting the die and the inner leads using metal wires; sealing the die, the inner leads, and the metal wires with a molding compound; separating the resulting joint QFN components into individual QFN components; and forming a second metal layer on the back surface of the I/O pads.

主权项

1. A method for manufacturing barrel-plating quad flat no-lead (QFN) packaging structure, comprising:
providing a metal substrate for a plurality of QFN components; forming a first photoresist film on a top surface of the metal substrate; forming a plating pattern in the first photoresist film using photolithography; forming a first metal layer comprising a plurality of inner leads in each one of the plurality of QFN components by a multi-layer electrical plating process using the plating pattern in the first photoresist film as a mask, such that a lead pitch of the plurality of inner leads is significantly reduced; attaching at least one die in a predetermined region on the top surface of the metal substrate for each one of the plurality of QFN components; connecting the at least one die and the plurality of inner leads using metal wires by a wire bonding process in each one of the plurality of QFN components; sealing the at least one die, the plurality of inner leads, and the metal wires in each one of the plurality of QFN components with a molding compound; etching a back surface of the metal substrate to form a plurality of I/O pads in each one of the plurality of QFN components corresponding to the plurality of inner leads; filling a sealant in etched areas at the back surface of the metal substrate; separating the plurality of QFN components into individual QFN components by a package sawing process; and forming a second metal layer on a back surface of I/O pads in the individual QFN components by a barrel plating process.