Enhanced Electrical Characteristics of Ge nMOSFET by Supercritical Fluid CO₂ Treatment With H₂O₂Cosolvent

Abstract

Significant improvements on Ge nMOSFET can be achieved by a novel low temperature supercritical phase fluid treatment with H <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> cosolvent. Thanks to the reduction of oxygen vacancy and unstable oxidation states, devices with the proposed treatment exhibit a low equivalent oxide thickness of 0.67 nm, 2-order reduction on gate leakage current, 7 times improvement on on-current, very low subthreshold swing of 79 mV/dev, high on/off current ratio, small hysteresis of 43.3 mV, low interface trap density, excellent uniformity and reliability characteristics.