Surface acoustic waves in c-axis inclined ZnO films

The frequency response of a 37 MHz bulk LiNbO3 surface acoustic wave (SAW) filter with a 200-nm-thick ZnO overlayer exhibited a downshift in the frequency with ultraviolet (UV) light due to acoustoelectric interactions between the photo-generated carriers in the semiconducting ZnO and the surface acoustic waves. In contrast, a 36 MHz ZnO thin film SAW delay-line with insulating ZnO films exhibited an upshift in the frequency. The response was more pronounced at higher harmonics (130–315 MHz) and was attributed to changes in the elastic/dielectric properties in the upper surface layer of ZnO. A linear change in the frequency with UV intensity shows immense applicability for wireless ultraviolet sensor applications.

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ZnO Based SAW Delay Line: Thin Film Characteristics and IDT Fabrication

MRS Proceedings ◽

10.1557/proc-785-d4.4 ◽

2003 ◽

Vol 785 ◽

Author(s):

Farid Hassani ◽

Shahrokh Ahmadi ◽

Can E. Korman ◽

Mona Zaghloul ◽

Shiva Hullavarad ◽

...

Keyword(s):

Acoustic Waves ◽

Delay Line ◽

Surface Acoustic Waves ◽

Rf Sputtering ◽

Device Fabrication ◽

Zno Films ◽

X Ray Diffraction ◽

Force Microscopy ◽

Atomic Force ◽

Interdigital Electrodes

AbstractZnO, a well-known piezoelectric material, is used to develop micro-scale Surface Acoustic Wave (SAW) delay line sensor. In this work, SAW delay line Devices are fabricated employing ZnO films that are deposited by RF sputtering technique. Films are characterized prior to device fabrication by X-Ray Diffraction (XRD) for film crystalline quality, UV-visible transmission spectroscopy for optical characteristics, and Atomic Force Microscopy (AFM) for surface morphology. Interdigital electrodes producing surface acoustic waves in the hundreds of MHz are developed by photolithography and metalization techniques. SAW delay line device testing, measurement and characteristics on RF sputtered ZnO films are presented and compared.

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High Velocity and High Coupling Surface Acoustic Waves Using ZnO Films on Ceramic Substrates with High Acoustic Velocity

Japanese Journal of Applied Physics ◽

10.7567/jjaps.24s1.124 ◽

1985 ◽

Vol 24 (S1) ◽

pp. 124 ◽

Cited By ~ 1

Author(s):

Fumio Takeda ◽

Tadashi Shiosaki ◽

Akira Kawabata

Keyword(s):

High Velocity ◽

Acoustic Waves ◽

Surface Acoustic Waves ◽

Acoustic Velocity ◽

Zno Films ◽

Ceramic Substrates

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Characterization of RF Sputtered ZnO Piezoelectric Films Using Transmission Electron Microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100114050 ◽

1975 ◽

Vol 33 ◽

pp. 86-87

Author(s):

Kemining W. Yeh ◽

Richard S. Muller ◽

Wei-Kuo Wu ◽

Jack Washburn

Keyword(s):

Integrated Circuit ◽

Acoustic Waves ◽

New Technology ◽

Surface Acoustic Waves ◽

Electromechanical Properties ◽

Leading Role ◽

Saw Devices ◽

Transmission Electron ◽

High Degree

Considerable and continuing interest has been shown in the thin film transducer fabrication for surface acoustic waves (SAW) in the past few years. Due to the high degree of miniaturization, compatibility with silicon integrated circuit technology, simplicity and ease of design, this new technology has played an important role in the design of new devices for communications and signal processing. Among the commonly used piezoelectric thin films, ZnO generally yields superior electromechanical properties and is expected to play a leading role in the development of SAW devices.

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