An integrated circuit and a method for using metal fill geometries to
reduce the voltage drop in power meshes. Metal fill geometries are
connected to the power mesh using vias or wires at multiple locations.
Metal fill geometries are connected to other floating metal fill
geometries using vias or wires at multiple locations. The circuit design
introduces maximum redundancy between metal fill geometries and power
mesh geometries, but partial redundancy between metal fill geometries and
metal fill geometries. In particular, the redundancy in connectivity
between metal fill geometries and metal fill geometries is kept minimal
to reduce the number of geometries introduced. The high redundancy
between metal fill geometries and power mesh geometries and the partial
redundancy among metal fill geometries result in a smaller IR-drop by
reducing the effective resistance on a power mesh. Hence, the invention
use redundancy carefully and advantageously to achieve simultaneous metal
density and IR-drop optimization without introducing excessive number of
metal fill geometries.