High-Performance SAW-Based Microfluidic Actuators Composed of Sputtered Al–Cu IDT Electrodes
Year: 2024
Type: article
Abstract: sFor the realization of highly sensitive SAW devices, Al-Cu thin films without novel metal were developed by combinatorial sputtering system. The Al-Cu sample library was grown with various chemical compositions and electrical resistivity, which provides important information for selecting the most suitable materials for SAW devices. From the viewpoint that the acoustic wave generated from the piezoelectric material is considerably affected by the resistivity and density of the IDT electrode, the Al-Cu film with Al content of 65 at% was finally selected as the IDT electrode material. The resistivity and density of the Al-Cu film, which can be applied as the IDT material for the SAW-based microfluidic actuator, are 6.0 x 10-5 Ω-cm and 4.4 g/cm3, respectively. The SAW device composed of Al-Cu IDT resonated at exactly 143 MHz without frequency shift and showed significantly improved acoustic performance with the insertion loss of -13.68 dB and FWHM of 0.41 dB. On the other hand, the SAW device composed of Au electrodes showed significantly degraded acoustic characteristics compared to the Al-Cu electrodes. The SAW-based microfluidic module fabricated with the optimized Al-Cu IDT electrode completely separated 5 μm PS particles even at high flow rates compared to that of Au IDT electrodes. This suggests that the lightweight and highly conductive Al-Cu IDT electrodes improved the resonance characteristics of the SAW device, which ultimately enhanced the acoustic radiation force transmitted to the PS particles in the microfluidic.
Source: Coatings
Authors: Hwansun Kim, Youngjin Lee, Peddathimula Puneetha, Sung Jin An, Jae-Cheol Park, Siva Pratap Reddy Mallem
Language: English
Subfield: Biomedical Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $2,955
OpenAlex ID: W4404186870