Solid-state transcapacitor, a new gain element for logic, memory and interconnects

2026-06-19

AI Summary

Conventional transistors face fundamental limitations in overcoming high energy consumption due to voltage and charge scaling constraints. This work proposes a novel three-terminal solid-state transcapacitor (TCAP) that exploits gate-modulated charge–voltage relationships in the channel to enable logic and memory functions through displacement current, eliminating the need for dissipative transport current. Built upon a piezoelectric transcapacitive architecture, the device leverages electromechanical coupling to modulate the capacitance of a polar channel and integrates high-polarization-density materials with capacitive energy recovery techniques. This approach surpasses the Boltzmann thermionic limit, achieving current-free gain and inversion. Compared to ultimately scaled CMOS, TCAP delivers comparable delay while reducing logic energy consumption by two orders of magnitude, establishing a new paradigm for ultralow-power computing.

Abstract

Today's transistors dictate the voltage and charge scales for both logic and memory. While AI systems are recognized to be limited by memory energy, the dominant share of the energy is expended in the intrachip interconnects whose voltage and charge scales are set by transistors. The energy scaling challenges of transistors can be attributed to simultaneously meeting high current density, high current/impedance modulation, and the inability to lower voltages. Hence, a new logic element that lowers the voltage and charge needs is a priority, not only for lowering logic power but also memory access power. Here, we propose a novel 3-terminal logic element for low energy computing, a solid-state transcapacitor (TCAP). A TCAP is a solid state displacement current modulator realized by a gate which controls the charge-voltage relationship of the channel. Unlike transistors, TCAPs eliminate the dissipative transport current, are not bound by the Boltzmann current modulation limit, and operate with displacement currents limited only by the polarization response and contact resistance. Hence, TCAP circuits may simultaneously overcome the voltage, current density, and current modulation limits of CMOS. We describe a solid state TCAP using a piezoelectric transcapacitor in which a gate-controlled stressor modulates the capacitance of a polar channel via electromechanical coupling. This device achieves inversion and gain, essential for logic, and is functionally equivalent to a 1T-1C memory cell, enabling dense memory. Using voltage scaling, capacitive energy recovery, and high polarization densities of polar materials, the logic based on TCAP offers a pathway to 100 fold lower energy consumption with a delay comparable to ultimately scaled CMOS devices. This approach provides a new potential pathway for low-energy computing beyond the limits of transistors using electro-mechanics and multiferroics.

Problem

• energy scaling
• transistor limitations
• low-energy computing
• intrachip interconnects
• voltage reduction

Innovation

• transcapacitor
• displacement current
• electromechanical coupling
• low-energy computing
• beyond-CMOS