Novel test circuit structures using selectively metal-covered transistors for a laser irradiation upset analysis

A quick and easy laser experiment for photocurrent induced upset investigations has been described as a preliminary test method for SEE experiments. In order to focus a laser beam on a desired transistor in complex LSI circuits, novel test circuit structures using selectively metal-covered transistors have been proposed. Photocurrent induced upsets have been successfully observed in a target CMOS inverter with an SR-FF detector. The laser irradiation upset has also been successfully observed in a selectively metal-covered CMOS SRAM cell. SEE test results are not explicitly shown in this paper.