The effects of TaN thickness and strained substrate on the performance and PBTI characteristics of poly-Si/TaN/HfSiON MOSFETs

The effects of TaN metal-gate thickness on the electrical characteristics of poly-Si/metal-gate/HfSiON MOSFETs have been investigated. Too thin TaN was reactive with poly-Si gate, which led to the formation of Si-doped metal gate. As a result, the work function of the metal gate was reduced and the capacitance increased while generating traps in HfSiON films. P-MOSFET using poly-Si/TaN gate with channel engineering in strained-Si substrate showed threshold voltage of - 0.45 V at W/L= 10/1 /spl mu/m and improved MOSFET characteristics.