SUBSTRATE EVALUATING DEVICE, SUBSTRATE EVALUATION METHOD, SUBSTRATE EVALUATION PROGRAM, AND RECORDING MEDIUM WITH THE SUBSTRATE EVALUATION PROGRAM STORED

PROBLEM TO BE SOLVED: To provide a substrate evaluation device for correctly calculating the return path of a signal line. SOLUTION: The substrate evaluating device 10 is provided with an input part 1, a layout preparing part 2, a storage part 3, a layout evaluating part 4, and an output part 5. The layout evaluating part 4 comprises a wiring determining part 4a for determining an evaluation wiring from among wirings included in a designed substrate; a plane-extracting part 4b for extracting a return plane having the possibility that the return path passes; a node-extracting part 4c for extracting a signal node representing the shape characteristics of an evaluation wiring; a candidate-extracting part 4d for extracting one or a plurality of return node candidates. having the possibility that the return path passes about each signal node; a path-extracting part 4e for extracting the shortest path from among the paths which connect the respective return node candidates as a return path; and a determining part 4f for determining the quality of a substrate design, on the basis of the shape of the return path and the shape of the evaluation wiring. COPYRIGHT: (C)2009,JPO&INPIT