Abstract
Previously, Lau [W. S. Law: Jpn. J. Appl. Phys. 29 (1990) L690] has pointed out that part of the hysteresis ΔV+ in MNS (Metal-Nitride-Silicon) capacitors is correlated to the spin density measured by electron spin resonance and the other part of the hysteresis ΔV- is correlated to defects close to the nitride/silicon interface. The spin density was thought to originate from silicon dangling bonds in the silicon nitride. 254 nm ultraviolet irradiation, which was known to be capable of producing silicon dangling bonds in silicon nitride, was found to induce a large ΔV+ in nearly hysteresis free MNS (Metal-Nitride-Silicon) capacitors, thus confirming that ΔV+ is correlated to silicon dangling bonds.