Performance Improvement of Monolithic CFET by Backside Enhanced Contact with C-type Source/Drain Contact Technology

In this paper, to optimized source/drain (S/D) contact in monolithic CFET, the backside enhanced contact (BSEC) technology is proposed and investigated by TCAD simulation, which can be used to form C-type S/D contact. Compared with the conventional L-type contact of common drain in monolithic CFET, the on-current (I<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">on</inf>) of bottom PFET with C-type S/D contact shows a 25.4% increase as the contact resistivity is 3e-9 Ω•cm<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup>, and the I<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">on</inf> of top NFET has little affects. Furthermore, the C-type S/D contact based on BSEC technology is conducive to further improving bottom PFET’s driving performance, relieving the I<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">on</inf> mismatch between PFET and NFET for monolithic CFET, and optimizing the transient characteristics of CFET inverter.