This paper presents results on the interfacial properties of Si3N4on NMOSFETs and PMOSFETs. Silicon nitride, formed by remote plasma enhanced chemical vapor deposition, was found to display severely degraded interfacial properties, in which the PMOS interfaces were significantly more degraded than NMOS interfaces. This is believed to be indicative of a relatively high density of interface traps located below the Si mid-gap that inhibit hole channel formation. These traps are believed to originate from the intrinsic nature of Si- Si3N4interface. Bonding constraint theory was applied to conclude that the Si-Si3N4interface is over-constrained compared to the Si-SiO2interface and consequently results in a higher intrinsic defectivity. A systematic study of the oxygen and hydrogen content in the silicon nitride film and its effect on electrical properties is also presented. Based on the electrical results it is concluded that the presence of oxygen either as a) a monolayer at the interface or b) within the silicon nitride film can produce high quality interfaces suitable for aggressively scaled CMOS devices.