US Patent 7227200 Metal I/O ring structure providing on-chip decoupling capacitance

There are provided a metal I/O ring structure for a semiconductor chip and a decoupling capacitance structure using the same. In the Metal I/O ring structure, a plurality of first metal lines are formed on a first metal layer and connected with a power supply voltage, and a plurality of second metal lines are formed on the first metal layer and connected with a ground voltage. The second metal lines are arranged neighboring to the first metal lines. The second metal lines are connected with a second metal layer disposed below the first metal lines on the metal layer, and the first metal lines are connected with the second metal layer disposed below the second metal lines on the first metal layer. An insulating layer is disposed between the first metal layer and the second metal layer, thereby forming a decoupling capacitance between the first metal lines and the second metal lines.