Dual gate synthetic WS<sub>2</sub> MOSFETs with 120μS/μm Gm 2.7μF/cm<sup>2</sup> capacitance and ambipolar channel
Dennis Lin, Xiangyu Wu, Daire Cott, Devin Verreck, Benjamin Groven, Stephanie Sergeant, Quentin Smets, Surajit Sutar, Inge Asselberghs, Iuliana Radu
Abstract
We have engineered dual gate WS2 transistors with scaled top and back gate stacks based on a surface physisorption ALD approach for advanced logic applications. Connected dual gate MOSFET operation with a 2ML WS2 channel reaches 210μA/um drain current and 2.7μF/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> capacitance (>3.4×10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">13</sup> /cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> sheet charge density) at 3V gate bias, with >10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">8</sup> on-off ratio, 120μS/um max. transconductance and 109mV/dec sub-threshold swing at 100nm Lch. This dual gate design enables us to explore EOT scaling, ambipolar I-V and C-V(capacitance-voltage) response on CVD WS <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> channel.