Electrical and Reliability Characteristics of FinFETs With High-k Gate Stack and Plasma Treatments

Effectsof high-k gate stacks and plasma treatments on electrical and reliability characteristics of FinFET were comprehensively studied in this work. A higher ON-current, higher ON-/OFF-current ratio, smaller subthreshold swing (S.S.), lower gate leakage current, and better reliability characteristics in FinFETs are simultaneously achieved by a HfO2/ZrO2/HfO2 gate stack. The improvement can be attributed to its higher k-value, fewer oxide traps, and oxygen vacancy in gate stack. A higher ON-current of FinFET can be obtained with an F-based plasma treatment, which, however, also induces a larger gate leakage current. A plasma treatment with F-and N-based ambient on gate stack is shown to obtain a higher ON-current and acceptable gate leakage in FinFET. Furthermore, a larger ON-current, higher ON-/OFF-current ratio, and a smaller S.S. in FinFET can be achieved with a TiO2 stacked gate dielectric.

Automated summary

The effects of high-k gate stacks and plasma treatments on the electrical and reliability characteristics of FinFET were comprehensively studied in this work. Different gate stack materials and plasma treatments were shown to achieve higher ON-current, higher ON-/OFF-current ratio, smaller subthreshold swing, and lower gate leakage current in FinFETs, leading to significant improvements in performance and reliability.