Compatibility of HfxTayN metal gate electrode with HfOxNy gate dielectric for advanced CMOS technology

Compatibility and thermal stability of the metal-oxide-semiconductor (MOS) device with HfOxNy gate dielectric and HfxTayN metal gate electrode were investigated. MOS device formed by HfxTayN metal gate and HfOxNy gate dielectric shows excellent thermal stability. Compared to the TaN metal gate, HfxTayN metal gate shows an enhancement in thermal stability and electrical characteristics, such as equivalent oxide thickness (EOT), hysteresis, interface trap density, stress-induced leakage current and stress-induced flatband voltage shift. With an increase in post metallization annealing (PMA) temperature, the electrical characteristics remain almost unchanged, which, in turn, demonstrate the excellent thermal stability and electrical reliabilities of the MOS device with HfOxNy gate dielectric and HfxTayN metal gate.