Study on electrical characteristics and reliability of fluorinated HfO2 for HKMG

The dielectric properties and reliability of fluorinated HfO2 have been studied. The fluorinated HfO2 dielectric treated by NF3 plasma showed improved dielectric characteristics but resulted in interfacial layer (IL) regrowth during the fluorine plasma treatment process, which led to an oxide capacitance reduction and poor electrical characteristics. Through the analysis of chemical composition and electrical characteristics, it has been revealed that the Hf–O bonds in HfO2 layer were converted to Hf–F bonds by the plasma treatment and then the dissociated oxygen diffused to the IL. In order to suppress the IL regrowth, newly fluorinated HfO2 has been developed. Reliability of fluorinated HfO2 dielectric was sharply improved without a decrease in the oxide capacitance at fluorine plasma treatment conditions of low power and temperature.

The fluorinated HfO2 dielectric treated by NF3 plasma showed improved dielectric characteristics but resulted in interfacial layer (IL) regrowth, which led to an oxide capacitance reduction and poor electrical characteristics. Reliability of newly fluorinated HfO2 dielectric was sharply improved without a decrease in the oxide capacitance at fluorine plasma treatment conditions of low power and temperature.Figure optionsDownload as PowerPoint slide