Test pattern generation method for avoiding false testing in two-pattern testing for semiconductor integrated circuit

摘要

A test pattern generation method for determining if a combinational portion 17 is defective, by applying test patterns to a semiconductor integrated circuit 10 and comparing responses to the test patterns with expected responses, the method including: a first step of generating test patterns having logic bits for detecting defects and unspecified bits; a second step of selecting critical paths 19, 19a, 19b generated by the application of the test patterns; a third step of identifying critical gates on the critical paths 19, 19a, 19b; and a fourth step of determining unspecified bits so that a critical capture transition metric, which indicates the number of the critical gates whose states are changed, is reduced; wherein by reducing the critical capture transition metric, output delays from the critical paths 19, 19a, 19b are prevented, and thereby false testing can be avoided.