Application of Non-contact Corona-Kelvin metrology for Characterization of Plasma Nitrided SiO2

In this paper we demonstrate an application of the micro corona-Kelvin metrology to monitoring of the electrical properties of silicon oxynitrides prepared with a plasma nitridation process currently used for advanced gate dielectrics. Key measurement parameters to be discussed are: dielectric capacitance equivalent thickness (CET), dielectric voltage in valence band tunneling range (VB), interface trapped charge (Qit) and flatband voltage. Negative polarity tunneling conditions are used as a measure of dielectric valence band. Taking advantage of the large valence band offset difference between Si3N4 and SiO2, we employ these tunneling measurements for very sensitive probing of the nitrogen content in SiON dielectrics.