This paper presents a technique that transforms large and complex RC networks into much smaller, physically realizable RC networks. These models reflect the transmission behavior of the initial network accurately for frequencies up to a user-defined maximal signal frequency. This technique has been incorporated in a layout-to-circuit extractor, using a scan-line approach. The method guarantees numerical stability and performs excellently in modeling RC interconnects. 1 Introduction This paper presents a solution to the major problem how to obtain a simple, passive and physically realizable RC network that matches the transmission behavior of a given very large and complex RC network up to a predefined maximal signal frequency. This problem is particularly acute in (3-D) layout-to-circuitextraction, where appropriate models for the IC interconnections in VLSI designs have to be generated. In most VLSI circuits, the IC interconnections and their parasitics play an essential role in th...