Electrical properties and detection methods for CMOS IC defects

CMOS failure modes and mechanisms and the test vector and parametric test requirements for the detection are reviewed. The CMOS stuck-open fault is discussed from a physical viewpoint, with results given from failure analysis of ICs having this failure mode. The results show that among functional, stuck-at, stuck-open, and I_DDQ test strategies, no single method guarantees detection of all types of CMOS defects. The I_DDQ test is the most sensitive and comprehensive, but can miss certain open-circuit defects and is a relatively slow measurement technique. The test-vector approach detects fewer of the CMOS defects, but can run at fast clock rates to detect certain open-circuit faults that may not be detectable by the I _DDQ test. Maximal CMOS IC defect detection involves a mixed-mode strategy of I_DDQ tests and vector stimulus/response tests