Interaction of surface acoustic waves and ultraviolet light in ZnO films

2003 ◽  
Vol 18 (3) ◽  
pp. 545-548 ◽  
Author(s):  
Parmanand Sharma ◽  
Sanjeev Kumar ◽  
K. Sreenivas
Keyword(s):  
Acoustic Waves ◽  
Delay Line ◽  
Uv Light ◽  
Surface Acoustic Waves ◽  
Zno Films ◽  
Zno Thin Film ◽  
Linear Change ◽  
Sensor Applications ◽  
Upper Surface Layer ◽  
Ultraviolet Sensor

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.

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

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.

Characteristics of surface acoustic waves excited by (1120) zno films deposited on R-sapphire substrates

2013 ◽  
Vol 60 (6) ◽  
pp. 1213-1218 ◽  
Author(s):  
Yan Wang ◽  
Shu-yi Zhang ◽  
Li Fan ◽  
Xiu-ji Shui ◽  
Zhong-ning Zhang ◽  
...  
Keyword(s):  
Acoustic Waves ◽  
Surface Acoustic Waves ◽  
Zno Films ◽  
Sapphire Substrates

Surface acoustic waves in c-axis inclined ZnO films

2002 ◽  
Author(s):  
G. Carlotti ◽  
D. Fioretto ◽  
G. Socino ◽  
L. Palmieri ◽  
A. Petri ◽  
...  
Keyword(s):  
Acoustic Waves ◽  
Surface Acoustic Waves ◽  
Zno Films

Harmonic Excitation of Surface Acoustic Waves on Gallium Nitride Thin Films for Biological and Chemical Sensor Applications

2012 ◽  
Vol 1415 ◽  
Author(s):  
J. Justice ◽  
L. E. Rodak ◽  
K. Lee ◽  
L. A. Hornak ◽  
D. Korakakis
Keyword(s):  
Thin Films ◽  
Gallium Nitride ◽  
Acoustic Waves ◽  
Chemical Sensor ◽  
Surface Acoustic Waves ◽  
Cost Effective ◽  
Harmonic Excitation ◽  
Higher Harmonics ◽  
Sensor Applications ◽  
Saw Devices

ABSTRACTGallium nitride (GaN) is a robust piezoelectric semiconductor with excellent thermal and chemical stability, making it an attractive material for surface acoustic wave (SAW) sensors operating in high temperature and harsh environments. The sensitivity of SAW devices is proportional to the square of the operating frequency. Therefore, high operating frequencies into the GHz regime are desirable for SAW sensors. For GaN, this requires sub-micron interdigital transducers (IDTs) when devices are designed to operate at the fundamental Rayleigh mode frequency. The necessity for sub-micron IDTs can increase fabrication costs and complexity. By designing SAW devices to operate at harmonic frequencies, GHz operation can be realized with relatively large IDTs, resulting in simpler and more cost effective solutions for GaN based SAW sensors. Devices have previously been designed to operate at the 5th and higher harmonics on lithium niobate, but there are no reports of using this technique on GaN in the literature. In this study, GaN thin films have been grown via metal organic vapor phase epitaxy on sapphire substrates. SAW devices designed to operate at the fundamental frequency and higher harmonics have been fabricated and measured. Operating frequencies greater than 2 GHz have been achieved using IDTs with 5 μm fingers. In addition, reduction of electromagnetic feedthrough around the 5th and 7th harmonic is demonstrated through varying ground electrode geometries.

Effect of Oxygen Flow Rate on the Properties of Nanocolumnar ZnO Thin Films Prepared Using Radio Frequency Magnetron Sputtering System for Ultraviolet Sensor Applications

2011 ◽  
Vol 364 ◽  
pp. 1-6 ◽  
Author(s):  
Mohamad Hafiz Mamat ◽  
Syafinaz Wan Anwar Wan ◽  
Mohamed Zahidi Musa ◽  
Zuraida Khusaimi ◽  
Mohd Firdaus Malek ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Oxygen Flow Rate ◽  
Oxygen Flow ◽  
Zno Thin Films ◽  
Zno Thin Film ◽  
Flow Rates ◽  
Sensor Applications ◽  
Ultraviolet Sensor ◽  
Sputtering System

Nanostructured zinc oxide (ZnO) thin films were deposited on glass substrates using radio frequency (RF) magnetron sputtering system at different oxygen flow rates ranges between 0 to 40 sccm. Field emission scanning electron microscopy (FESEM) images was revealed that nanocolumnar ZnO structure thin films are produced on the substrates using high purity ZnO as the target at RF power of 250 W in the argon and oxygen gas mixture ambient. The XRD spectra reveal that the deposited films are preferentially grown along the c-axis indicating high ZnO crystallinity. The ultraviolet-visible (UV-Vis) spectra show that all samples are very transparent in the visible region (400 – 800 nm) with average transparency above 80 %. The photocurrent properties indicate that ZnO thin film prepared at oxygen flow rate of 20 sccm has the optimum characteristic for ultraviolet sensor applications. This finding suggested that the oxygen flow rates play important role and has critical value for semiconducting nanocolumnar ZnO growth in the sputtering system, which can produce ZnO thin film with high sensitivity of ultraviolet detection.

scholarly journals The Application of the Theory of Synthesis of a Delay Line with a Surface Acoustic Wave for a Single-Mode Oscillator of Electric Signals in Some Sensors of Non-Electrical Quantities

2017 ◽  
Vol 24 (3) ◽  
pp. 563-576
Author(s):  
Milan Šimko ◽  
Miroslav Gutten ◽  
Milan Chupáč ◽  
Daniel Korenčiak
Keyword(s):  
Theoretical Analysis ◽  
Acoustic Wave ◽  
Surface Acoustic Wave ◽  
Acoustic Waves ◽  
Delay Line ◽  
Surface Acoustic Waves ◽  
Single Mode ◽  
Delay Lines ◽  
Electronic Components ◽  
Electric Signals

AbstractThe paper deals with the issue of constructing delay lines on the basis of surface acoustic waves and their application to single-mode oscillators. As a result of a theoretical analysis concrete delay lines are proposed.In the contribution, there is presented a theory of designing a symmetrical mismatched and matched delay line for a single-mode oscillator of electrical signals on the basis of which there were designed and fabricated acoustic-electronic components for sensors of non-electrical quantities.From the experimental results it can be stated that all of six designed and fabricated delay lines can be effectively used in the construction of single-mode oscillators.

An ultraviolet sensor using spin–coated ZnO nanoparticles based on surface acoustic waves

2013 ◽  
Vol 111 ◽  
pp. 105-109 ◽  
Author(s):  
Ki Jung Lee ◽  
Haekwan Oh ◽  
Minuk Jo ◽  
Keekeun Lee ◽  
Sang Sik Yang
Keyword(s):  
Zno Nanoparticles ◽  
Acoustic Waves ◽  
Surface Acoustic Waves ◽  
Ultraviolet Sensor
Sign in / Sign up

Export Citation Format

Share Document