Low-temperature Crystallization and Paraelectric-ferroelectric Phase Transformation in Nanoscale ZrO2 Thin Films Induced by Atomic Layer Plasma Treatment
In recent years, Hf/ZrO2-based thin films have emerged as promising candidates for ferroelectric materials in various applications. However, achieving ferroelectricity with a low-temperature process has remained a challenging task. In this study, the atomic layer plasma treatment (ALPT) technique, where an in-situ Ar plasma treatment is introduced into each atomic layer deposition (ALD) cycle, was used to achieve crystallization and ferroelectricity in as-deposited ZrO2 thin films at a low temperature of 250°C. The ALPT treatment effectively contributes to a high-temperature annealing effect, leading to enhanced crystallization and densification of the films. In addition, the ALPT process also induces a transformation from paraelectric to ferroelectric orthorhombic phase in as-deposited ZrO2 thin films, exhibiting a high ferroelectric switching polarization of 30 μC/cm2 along with great endurance characteristics up to 108 switching cycles. This study demonstrates that ALPT is a highly effective approach to enhance and tailor the crystallization and dielectric characteristics of nanoscale thin films at a low temperature, which is highly advantageous and demanded in a variety of applications and research fields encompassing nanoelectronic, energy storage, and biomedical devices.
- This article is part of the themed collection: Journal of Materials Chemistry C HOT Papers