P-Type Ternary Logic MOSFET With Tunable Middle State Using Bidirectional Threshold Switching

Abstract

A p-type ternary logic MOSFET (P-TMOS), which serves as the counterpart to a previously reported n-type ternary logic MOSFET (N-TMOS) but has been missing for the construction of a complementary standard ternary inverter, is demonstrated. The P-TMOS consists of a PMOS and an n-type threshold switch (TS) connected in series. While the PMOS determines the type of the ternary logic device, the TS, despite being an n-type device, provides both n-type and p-type characteristics, making it bidirectional with a tunable middle state in ternary logic. This tunable middle state is attractive for balancing noise margin and controlling power-delay product. By leveraging mature CMOS technology capable of large-scale fabrication, the Si-based P-TMOS facilitates the practical implementation of a ternary logic system.