ALPS2 A Standard Cell Layout System for Double-Layer Metal Technology

A layout style for double-layer metal standard cell design is described. Based on this particular style, an automatic layout system (ALPS2) is developed. It mixes state of the art placement and routing techniques in different stages of the layout process, which deviates from the traditional place-first-then-route strategy, and produces efficient results. The chip area comparisons between three single layer metal standard cell designs and those of the ALPS2 system showed up to 18% reduction by using the second layer metal.