DENSE-PITCH SMALL-PAD COPPER WIRE BONDED DOUBLE IC CHIP STACK PACKAGING PIECE AND PREPARATION METHOD THEREFOR

摘要

A dense-pitch small-pad copper wire bonded double IC chip stack package comprises a plastic package body, in which a lead frame carrier and a frame lead inner pin are arranged; the upper surface of the lead frame carrier is fixedly connected with a first IC chip; a second IC chip is stacked on the first IC chip; the upper surface of the first IC chip and the upper surface of the second IC chip are respectively provided with a plurality of pads which are arranged as two lines of pad groups in parallel; the two pad groups are respectively a first pad group and a second pad group; a metal ball is implanted on each pad; each metal ball is connected with a first copper bonding ball; and a third copper bonding wire is formed by looping and arching on a corresponding metal ball between the second IC chip and the first IC chip. The preparation process of the present invention comprises thinning, scribing, loading the chip, performing pressure welding, plastic packaging and post-curing, trimming, electroplating, printing, forming and separating, and packaging. The package and the preparation method of the invention avoid the hidden danger of open circuit of a plastic packaging punching wire caused by the crater on the pad, the short circuit of adjacent welding spots, and the easy damage of a previous wire.

主权项

1. A dense-pitch small-pad copper wire bonded double IC chip stack package, comprising a plastic package body, wherein a lead frame carrier and a frame lead inner pin are arranged in the plastic package body; the upper surface of the lead frame carrier is fixedly connected with a first IC chip; a second IC chip is stacked on the first IC chip, wherein the upper surface of the first IC chip and the upper surface of the second IC chip are respectively provided with a plurality of pads which are arranged as two lines of pad groups in parallel; the two pad groups are respectively a first pad group and a second pad group; a metal ball is implanted on each pad; each metal ball is connected with a first copper bonding ball; and a third copper bonding wire is formed by arching on a corresponding metal ball between the second IC chip and the first IC chip; wherein the first pad group and the second pad group are respectively welded with one metal ball on the spaced pads; the metal ball in the first pad group and the metal ball in the second pad group are alternatively arranged; a first copper bonding ball is welded on each metal ball; a second bonding ball is respectively welded on the pad not welded with the metal ball in each line of pad group; moreover, a copper bonding spot is punched on the corresponding frame lead inner pin to form a second copper bonding wire.