APPARATUS FOR AUTOMATIC PLACEMENT AND ROUTING, METHOD FOR ITS AUTOMATIC PLACEMENT AND ROUTING, AND SEMICONDUCTOR INTEGRATED CIRCUIT FORMED BY METHOD FOR ITS AUTOMATIC PLACEMENT AND ROUTING

摘要

PROBLEM TO BE SOLVED: To prevent the residual between wirings and over etching of the wirings by arranging dummy cells without decreasing wiring characteristics and then by easily setting a wiring data rate at a proper value.;SOLUTION: In a layout design of a semiconductor integrated circuit, functional blocks (2) are arranged and wired mutually by a placement/routing means 102, the wiring data rate that shows the percentage of the area of a wiring portion is calculated by a wiring data rate calculation part 104 from the result of this placement/routing, and it is determined whether it is not less than a prescribed value by a wiring data rate determination part 105. If it is less than the value, a dummy cell (4) to be added is calculated by a dummy cell calculation part 106, the region having no wirings is detected by a space region detection part 108, and the dummy cell to be added is arranged by a dummy cell placement part 108. As a result, the wiring data rate can be set at the proper value.;COPYRIGHT: (C)2002,JPO