Performance Improvement Of Mosfet With Hfo2-Al2o3 Laminate Gate Dielectric And Cvd-Tan Metal Gate Deposited By Taimata

For the first time, we integrated HfO2-Al2O3 laminate gate dielectric with CVD-TaN metal gate deposited by TAIMATA (tertiaryamylimidotris dimethylamidotantalum) in n/pMOSFETs. It was found that TaN films with low impurity contents were required for optimized capacitance. Together with a slight improvement of the transconductance and a substantial gain in inversion EOT with HfAlO/TaN, improved current drivability was observed in comparison to nitrided-SiO2/poly-Si and HfAlON/poly-Si with similar EOTs. In addition, CVD-TaN resulted in improved J(g) characteristics showing F-N tunneling behavior with an effective barrier height of 1.1eV in nMOS in the inversion region. Theses results suggest that CVD-TaN metal gate is necessary for the implementation and scaling of high-k gate dielectrics.