Design of the Interconnected Mesh Power System (IMPS) MCM Topology

A significant decrease in MCM substrate production cost can be achieved by reducing the number of substrate layers from the conventional four or five (power, ground, X signal, Y signal, pad) to two or three. Besides reducing direct processing steps, yield will also increase as defect producing operations are eliminated. This paper describes the Interconnected Mesh Power System (IMPS), a new interconnection topology which leverages the production technologies of fine line lithography and batch via generation to allow planar power and ground distribution, and dense signal interconnection, on only two metal layers. Several possible implementations of the topology in MOM-D and MCM-L are described. The approach to incorporating IMPS in a standard commercial MCM design system is presented. The impact of a preferential routing scheme and a standardized pad structure is described. The design of a test vehicle which characterizes both the signal transmission and power distribution properties of the IMPS topology is discussed. Preliminary results of electrical characterization are described.