论文信息 - Highly-reliable, low-resistivity bcc-Ta gate MOS technology using low-damage Xe-plasma sputtering and Si-encapsulated silicidation process

Highly-reliable, low-resistivity bcc-Ta gate MOS technology using low-damage Xe-plasma sputtering and Si-encapsulated silicidation process

We present for the first time highly reliable metal-gate MOS technology with low-resistivity bcc-Ta. Low sheet resistance of 1.7 /spl Omega//sq. has been obtained by precisely controlling the ion bombardment conditions during Ta sputtering process, and by employing Si-encapsulation technique to suppress oxidation or hydrogen-accumulation in Ta thin film. By comparing Ta-gate and poly-Si gate MOS devices, it is confirmed that Ta-gate structure does not induce significant degradation in the gate-oxide reliability by using low-damage Xe-plasma sputtering and the Si encapsulation technique. It is also demonstrated that carrier mobility/velocity in the inversion layer of Ta gate SOI MOSFET is slightly higher than that of poly-Si gate SOI MOSFET because of higher thermal-conductivity of the metal gate.

[1] Tadahiro Ohmi,et al. Tantalum-gate thin-film SOI nMOS and pMOS for low-power applications , 1997 .

[2] Tadahiro Ohmi,et al. Reliable tantalum-gate fully-depleted-SOI MOSFET technology featuring low-temperature processing , 1997 .

[3] T. Ohmi,et al. Ion energy, ion flux, and ion species effects on crystallographic and electrical properties of sputter-deposited Ta thin films , 1997 .