Ferroelectric AlScN thin films with enhanced polarization and low leakage enabled by high-power impulse magnetron sputtering


Date

2025-05

Publication Type

Journal Article

ETH Bibliography

yes

Citations

Altmetric

Data

Abstract

The demand for efficient data processing motivates a shift toward in-memory computing architectures. Ferroelectric materials, particularly AlScN, show great promise for next-generation memory devices. However, their widespread application is limited due to challenges such as high coercive fields, leakage currents, and limited stability. Our work introduces a novel synthesis approach for ferroelectric AlScN thin films using high-power impulse magnetron sputtering (HiPIMS). Through a combinatorial study, we investigate the effect of scandium content and substrate bias on the ferroelectric properties of AlScN films deposited using metal-ion synchronized (MIS) HiPIMS. Leveraging the high ionization rates of HiPIMS and optimally timed substrate bias potentials, we enhance the adatom mobility at low temperatures. Our films exhibit a high degree of texture and crystallinity as well as low roughness at temperatures as low as 250 °C. Most importantly, the films exhibit coercive fields comparable to state-of-the-art values (5 MV/cm) with significantly enhanced remanent polarization (158–172 μC/cm2). Notably, the remanent polarization remains stable across varying scandium concentrations. We further evaluate cycling stability and leakage current to assess suitability for memory applications. This study demonstrates HiPIMS as a scalable and CMOS compatible technique for synthesizing high-quality ferroelectric AlScN films, paving the way for their application in non-volatile memory applications.

Publication status

published

Editor

Book title

Journal / series

Volume

13 (5)

Pages / Article No.

51123

Publisher

American Institute of Physics

Event

Edition / version

Methods

Software

Geographic location

Date collected

Date created

Subject

Organisational unit

03918 - Fiebig, Manfred / Fiebig, Manfred check_circle

Notes

Funding

22-2 ETH-016 - Freestanding antipolar thin films for flexible oxide electronics (ETHZ)
188414 - Multifunctional oxide electronics using natural ferroelectric superlattices (SNF)
231428 - 10002402 - Optical control of ferroelectric polarization in oxide thin films (SNF)

Related publications and datasets