Low Equivalent Oxide Thickness and Leakage Current of pGe MOS Device by Removing Low Oxidation State in GeO<sub>x</sub> With H<sub>2</sub> Plasma Treatment
Dun‐Bao Ruan, Kuei‐Shu Chang‐Liao, Shih-Han Yi, Hsin-I Yeh, Guanting Liu
Abstract
A low equivalent-oxide-thickness of 0.58 nm and a low gate leakage current density of ~2×10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-5</sup> A/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> at V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">G</sub> = V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">FB</sub> - 1 V in p-substrate Ge (pGe) MOS device can be simultaneously achieved by a hydrogen plasma (H*) treatment on GeO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> interfacial layer (IL). It is found that the removal of GeO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</sub> with low oxidation state in GeO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> IL play crucial roles on electrical characteristics of pGe MOS device. Through a H* treatment, the electrical and reliability characteristics are improved by a GeO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> IL with high oxidation state. Therefore, a GeO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> IL with H* treatment is promising for high performance pGe MOS devices.