Advancing 2D Monolayer CMOS Through Contact, Channel and Interface Engineering
K. P. O'Brien, C. J. Dorow, Ashish Verma Penumatcha, K. Maxey, S. Lee, Carl H. Naylor, Andy Hsiao, B. Holybee, Carly Rogan, Dominique Adams, Tristan A. Tronic, Shuo Ma, A. Oni, Arnab Sen Gupta, Robert Bristol, Scott B. Clendenning, M. Metz, Uygar E. Avci
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.