As manufacturers attempt to reduce the size of electronic devices, they may find ways to combine integrated circuit dies in order to make the electronics of the device more compact. One typical way to connect multiple integrated circuit dies may be to stack the dies vertically as tiers, using vias to connect the circuitry between the tiers of dies. This may result in the heat generated by the circuitry of a lower substrate propagating upwards through the stacked dies. This may add to the heat already generated by the circuitry of the upper tiers of dies, thus decreasing the reliability of the upper tiers of dies.
Another method may locate dies side-by-side and use wire bonding to connect circuits between each. This may result in longer bond wires that may be more susceptible to breakage as well as a larger total package size.
There are general needs for combining multiple integrated circuits in a relatively small package.