The use of test structures to identify leakage failure mechanisms in CMOS inputs

Abstract

An input structure is dissected into simple components and into combinations of components, and is processed so that the device performance under stress can be clearly understood. The study of leakage currents in these structures is then used to identify the location and cause of leakage in a complete device. The failure mechanism is shown to be caused by inversion at the edge of the n/sup +/V/sub dd/ connection of the thick oxide protection diode.<>