Semiconductor device having test element and method of testing using same

Abstract

A CMOS transmission gate (9) serving as a test element is connected to an input of a semiconductor element to be tested through an interconnect line (13), and an input signal is applied to the semiconductor element through the CMOS transmission gate (9). The application of the input signal causes a potential change to occur at PN junction surfaces between source/drain regions (7a, 7b, 8a, 8b) of N-channel and P-channel MOS transistors (NT1, PT1) constituting the CMOS transmission gate (9) and wells (1, 2). An LVP (Laser Voltage Probe) technique is used to direct a near infrared laser beam (10) onto the PN junction surfaces through the backside of a semiconductor substrate (15), and to measure the intensity of a reflected beam from the PN junction surfaces, thereby detecting the potential change at the PN junction surfaces.

Dependencies are inferred from the claim text.