Reconfigurable Si field-effect transistors with symmetric on-states enabling adaptive complementary and combinational logic

Abstract

Reconfigurable field-effect transistors (RFETs), combining n- and p-type operation in a single device, have already shown promising simulation results for enhancing performance and functionality in conventional devices and further enabling novel adaptive computing concepts. With recent advances in the formation of high-quality monolithic and single-crystalline Al-Si Schottky contacts providing a reproducible way to fabricate RFETs with highly symmetric n-and p-type operation, we are now able to demonstrate their integration in fundamental complementary and combinational logic circuits. In this regard, we show an inverter, as well as NAND/ NOR and XOR/ XNOR gates, capable of dynamically run-time switching their operation mode, while simultaneously reducing transistor count compared to conventional circuits with static transistors. Importantly, we could demonstrate their reliable operation using only fully symmetric supply voltages while providing a full output swing. Their robust operation is verified by analyzing their noise margins, stability to input voltage variations, and transient behavior. Most notably, the presented device concept and the Al–Si material system are potentially compatible with the state-of-the-art complementary metal–oxide–semiconductor (CMOS) processing technology, paving the way for future hybrid reconfigurable-CMOS circuits with improved functional density and energy efficiency.