Characteristics of fluorine implantation for HfO₂ gate dielectrics with high-temperature postdeposition annealing

In this work, we describe the characteristics of silicon surface fluorine implantation (SSFI) for HfO₂ films with high-temperature postdeposition annealing. The thermal stability of HfO₂ gate dielectrics is much improved owing to the incorporation of fluorine into HfO₂ thin films. The gate leakage current of the SSFI HfO₂ films is about three orders less than that of samples without any fluorine implantation. In addition, improvements in stress-induced leakage current (SILC) and charge trapping characteristics are realized in the HfO₂ films with the SSFI. The incorporation of fluorine atoms into the HfO₂ films reduces not only interface dangling bonds but also bulk traps, which is responsible for the improvements in properties.