Monolithic GaN Systems Combining Non-Volatile Memory and Analog Computing via Area-Ratio-Engineered Ferroelectric AlScN Gate Stacks

Abstract: Gallium nitride (GaN) transistors have become the platform of choice for power electronics and radio-frequency power amplifiers. To unlock capabilities beyond those of conventional GaN, integrating ferroelectric heterostructure has been considered toward memory, logic and reconfigurable systems. Here, we demonstrate ferroelectric GaN transistors employing an AlScN-based gate stack in which systematic engineering of the area-ratio (SMIS/SMFM) provides unified control over both memory and analog functionality. Precise modulation of the intermediate electrode length yields a record memory window of 27 V and a forward subthreshold swing of 27 mV/dec, driven by ferroelectric polarization reversal of a robust downward-polarization state pre-induced by two-dimensional electron gas. Low area-ratio devices (SMIS/SMFM = 1, 2) achieve 4-bit multi-level cell operation and excellent spatial uniformity across a fabricated 4 x 4 array, benchmarking favorably against established silicon and oxide ferroelectric architectures. High area-ratio devices (SMIS/SMFM = 4, 8) harness continuously tunable conductance states to demonstrate multi-state inverters and the first GaN-based ferroelectric frequency-to-voltage converter, delivering a linear frequency-voltage response across 0.5 - 500 Hz range with a conversion gain of 1.1 mV/Hz. This work establishes routes towards monolithically integrated GaN systems that combine non-volatile memory and analog signal processing on a platform inherently suited to high-power and radio-frequency applications.