3d chip assemblies using stacked leadframes

Abstract

A stacked-chip assembly including a plurality of IC chips or die that are stacked, and a plurality of stacked leads. Leads from separate leadframes may be bonded together so as to tie corresponding metal features of the various chips to a same ground, signal, or power rail. Each leadframe may include a center paddle, which is disposed between two chips in the stack. The center paddle may function as one or more of a thermal conduit and common electrical rail (e.g., ground). The leadframes may be employed without the use of any bond wires with leads bonded directly to bond pads of the chips. A first IC chip may be mounted to a base leadframe and subsequent die-attach leadframes and IC chips are stacked upon the first IC chip and base leadframe. The die-attach leadframes may be iteratively bonded to an underlying leadframe and the bonded stacked leads stamped out of their respective leadframe sheets.