Selvaraj, Manju Priya and Sen, Shrabanee (2026) RF-Sputtered AlScN Thin Films with Ti/Au Electrodes on Flexible Kapton Substrate for Damage Assessment at High Temperatures. In: International Conference on Recent Advances in Materials Processing and Characterization, 13-15 March 2026, NIT Jamshedpur. (Submitted)

Full text not available from this repository. (Request a copy)

Abstract

Conventional piezoelectric materials such as lead zirconate titanate (PZT) are limited to operating temperatures below 300°C due to thermal instability and environmental toxicity concerns associated with lead content. Aluminium nitride (AlN), while thermally stable up to ~900°C, exhibits relatively low piezoelectric coefficients (d₃₃~5pC/N), limiting sensitivity. Aluminium scandium nitride (AlScN) overcomes these limitations by combining superior thermal stability (>1000°C), an exceptionally high piezoelectric coefficient (d₃₃~20-25 pC/N) approximately five times higher than AlN). Its ultra wide band gap and compatibility with flexible substrates make it an ideal material platform for next-generation high-temperature structural health monitoring sensors. In this work, we report the synthesis and comprehensive dielectric characterization of RF-sputtered AlScN thin films. Aluminium Scandium Nitride (AlScN) thin films were deposited on flexible Kapton substrates via RF magnetron sputtering, utilizing Ti as an adhesion layer and Au as the bottom electrode. The films achieved uniform thickness (~1.5 µm) post-heat treatment, as confirmed by surface profilometry. Scanning Electron Microscopy (SEM) revealed dense, crack-free microstructures with excellent interface quality between the AlScN layer and electrodes. Cross-section SEM image revealed clear distinction between layers. Comprehensive dielectric characterization was conducted through frequency-dependent capacitance and dissipation factor measurements (100 Hz to 1 MHz) under ambient conditions using impedance spectroscopy. The AlScN based devices exhibited stable capacitance and remarkably low dielectric loss tangent values across the measured frequency range, indicating superior electrode–film interfaces and material uniformity. The enhanced dielectric properties are attributed to scandium incorporation into the AlN lattice, which increases the piezoelectric coefficient and dielectric constant compared to pure AlN. These results demonstrate that RF-sputtered AlScN on flexible substrates with optimized Ti/Au electrode configurations produces high-quality thin films suitable for future development of low-power, reliable sensing. The combination of high thermal stability, low-loss dielectric response and integration with flexible substrates make these structures as promising candidates for potential applications in structural health monitoring of engineering components under demanding conditions.

Item Type:	Conference or Workshop Item (Poster)
Subjects:	Engineering Materials
Divisions:	Sensor and Actuator
Depositing User:	Ms Upasana Sahu
Date Deposited:	12 May 2026 17:02
Last Modified:	12 May 2026 17:02
URI:	https://cgcri.csircentral.net/id/eprint/5814

Actions (login required)

View Item