Flexible surface acoustic wave resonators built on disposable plastic film for electronics and lab-on-a-chip applications

Abstract

Flexible electronics are a very promising technology for various applications. Several types of flexible devices have been developed, but there has been limited research on flexible electromechanical systems (MEMS). Surface acoustic wave (SAW) devices are not only an essential electronic device, but also are the building blocks for sensors and MEMS. Here we report a method of making flexible SAW devices using ZnO nanocrystals deposited on a cheap and bendable plastic film. The flexible SAW devices exhibit two wave modes - the Rayleigh and Lamb waves with resonant frequencies of 198.1 MHz and 447.0 MHz respectively, and signal amplitudes of 18 dB. The flexible devices have a high temperature coefficient of frequency, and are thus useful as sensitive temperature sensors. Moreover, strong acoustic streaming with a velocity of 3.4 cm/s and particle concentration using the SAW have been achieved, demonstrating the great potential for applications in electronics and MEMS.

NH3 sensing property and mechanisms of quartz surface acoustic wave sensors deposited with SiO2, TiO2, and SiO2-TiO2 composite films

“…To achieve this goal, various types of ammonia sensors, such as metal oxide semiconductor sensors, electrochemical sensors and surface acoustic wave (SAW) sensors were developed, [13][14][15][16][17]. Benefiting from the significant development of RF and crystal technologies, surface acoustic wave techniques (SAWTs) are playing important roles in our daily life [18][19][20][21].…”

Shapeable magnetoelectronics

“…MI/GMI sensors could be utilized in a wireless fashion, e.g., through integration with surface acoustic wave devices 121 on flexible substrates to obtain passive and wireless magnetic sensing devices. 122 For wireless applications, magnetic sensors working in the high frequency region (GHz) are favorable as the device and antenna size are inversely proportional to the operating frequency.…”

AlScN thin film based surface acoustic wave devices with enhanced microfluidic performance

“…silicon, glass, metal, or polymer). 7,[10][11][12][13] Currently, piezoelectric thin films such as ZnO have been extensively explored for SAW based sensors and microfluidics. 6,7,14 AlN, another extensively used piezoelectric film materials in microelectro mechanical system (MEMS), has great advantages such as high acoustic velocity, outstanding stability at high temperatures, excellent chemical inertness and good compatibility with CMOS process.…”