Lead frame having layered conductive planes

Abstract

A lead frame having layered conductive planes is disclosed for use in semiconductor devices. The lead frame includes a plurality of long leads each having a lead tip and a plurality of short leads. Electrically conductive layers are attached to the long leads around such that they don't cover the tips of the long leads and are radially inward of the short leads. The conductive layers are insulated from the long lead and each other by adhesive insulating layers. In a preferred embodiment, the top conductive layer has a smaller width than the bottom conducting layer and is positioned to expose an inner and outer ledge on the bottom conducting layer. The exposed outer ledge allows bonding to the shorter leads. The use of shorter leads decreases the amount of inductance in the leads. The conductive layers also may act as capacitors. In one embodiment of the present application the short leads may correspond to ground and/or power leads. The decreased inductance and increased capacitance decreases the impedance seen in the power and ground leads. This allows the semiconductor to operate at higher speeds and consume less power.