| As metal-oxide-semiconductor (MOS) device feature sizes are scaled, stringent requirements have been placed on advanced gate dielectrics, their processing and characterization. As the gate insulator thickness reduces to 3.0 nm and below, issues such as impurity penetration, dielectric reliability, mobility degradation, and leakage current become critical. In this work, the electrical and material properties of silicon oxynitride gate dielectrics formed by Rapid Thermal Chemical Vapor Deposition (RTCVD) were investigated. It will be shown that RTCVD and post-deposition annealing allows for control of both the concentration and distribution of nitrogen in ultrathin dielectrics. A comparison of material characterization methodologies for these gate dielectrics was made. Detailed analysis of the electrical characterization methodologies required for ultrathin gate dielectrics was performed. The results of this characterization indicate that RTCVD silicon oxynitride for use in ultrathin gate dielectrics and stacked dielectrics with combinations of oxides and RTCVD oxynitrides provide viable alternatives for gate dielectrics down to the 2.0 nm regime. |
