Significance of Nitrogen and Aluminum Depth Profile Control in HfAlON Gate Insulators

摘要

Aluminum and nitrogen depth-profile dependences of the electron mobility are examined. We show that the electron mobility for MOSFETs with HfAlON gate dielectrics in which nitrogen and aluminum depth profiles are controlled is strongly affected by the nitrogen profile rather than the aluminum one, although the nitrogen profile does not affect the V{sub}(FB) shift. These results suggest that additional scattering due to nitrogen incorporation cannot be explained by only the Coulombic components such as the fixed charges. An appropriate profile control of the nitrogen to suppress the mobility degradation is a key for obtaining high performance MOSFETs with HfAlON dielectrics.