Advancing 2D Monolayer CMOS Through Contact, Channel and Interface Engineering

Abstract

2D CMOS transistors fabricated with transition metal dichalcogenide (TMD) materials are a potential replacement for silicon transistors at sub-12 nm channel length [L <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">G</inf> ]. We demonstrate record NMOS contacts using a high melting point metal, down to 146 Ω-µm contact resistance (Rc). We present the best PMOS performance on a grown monolayer WSe2 film with 50 µA/µm Ion and 141 mV/dec sub-threshold swing (SS) using a Ru contact metal, showing record PMOS contact resistance, Rc = 2.7 kΩ-µm. For the first time, we present 300 mm wafer growth options of 4 different 2D TMD films: MoS <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> , WS2, WSe2, MoSe2 that were grown at BEOL compatible temperatures. On unpassivated channel devices we show two methods of channel curing. First, N2 desiccation can improve ION (~2x) and SS (~0.6×) simultaneously. Secondly, FGA annealing can improve bare channel devices by increasing their median Ion by 10× and lowering their SS by almost 50%. Finally, we benchmark our results against leading grown TMD devices, demonstrating record drive-currents among devices with good SS.