Electrical Characteristics and Thermal Stability of $ \hbox{Hf}_{x}\hbox{Ta}_{y}\hbox{Si}_{z}\hbox{N}$ Metal Gate Electrode for Advanced MOS Devices

To continuously improve device performance with the shrinkage of device dimension, some novel devices like fully depleted silicon-on-insulator and symmetric double-gate transistor have been proposed. Various Hf
_x
Ta
_y
Si
_z
N metal gate electrodes were developed in this paper to achieve work function near the midgap and excellent thermal stability. Furthermore, this paper also demonstrated a good metal gate candidate, Hf
_0.19
Ta
_0.41
Si
_0.26
N
_0.14
, possessing excellent electrical performances in hysteresis effect, interface trap density, stress-induced leakage current, and excellent thermal stability as well.