Enhanced performance of Si MOS capacitors with HfTaOxNy gate dielectric by using AlOxNy or TaOxNy interlayer

Si MOS capacitors with HfTa oxide and oxynitride as gate dielectric were fabricated. Moreover, AlO_xN_y or TaO_xN_y was used as the interlayer between HfTa oxynitride and Si substrate to improve the electrical quality of the capacitors. Experimental results showed that the HfTaO_xN_y capacitor with TaO_xN_y interlayer achieved better performance with larger capacitance and smaller leakage current than its counterpart with AlO_xN_y interlayer.