Negative Differential Transconductance Induced by Electrostatic Doping in Multi‐Functional Si Field‐Effect Transistors

Abstract

The implementation of adaptive multifunctional transistors is key to improving data processing capabilities and overcoming the scaling and power density limitations of conventional complementary metal-oxide-semiconductor (CMOS) technology. In this context, anti-ambipolar transistors (AATs) enabling negative differential transconductance (NDT) characteristics hold promise of enhancing the performance and functionality of computational systems by implementing multivalued logic (MVL). Here, we demonstrate a Si-based multi-functional run-time reconfigurable transistor with a distinct hysteresis-free AAT mode showing stable and reproducible NDT characteristics through precise carrier polarity control. The proposed multi-gate device exhibits a bias voltage-tunable room temperature peak-to-valley ratio (PVR) up to approximately 10⁷ and bias-independent ultra-low off-state currents below 50 fA, strongly surpassing the capabilities of state-of-the-art negative differential resistance (NDR) diodes and transistors. A detailed and systematic study of the NDT characteristic revealed stable device operation beyond 400 K. Most notably, the demonstration of NDT in a Si-based AAT FET may contribute to the co-integration of high-frequency doublers, spiking neuron circuits, and MVL alongside conventional CMOS technology.