Work Function Effects of Nano Structured ZnO Thin Film on the Acetone Gas Sensitivity

AbstractWe deposited various nano structured ZnO thin films with plasma treatment on an alumina substrate and fabricate ZnO sensors for acetone detection. The ZnO sensors with various nano structures and the plasma treatment were deposited by radio frequency (RF) magnetron sputtering method with RuO2 micro heater and Ru electrode. In order to control a work function intentionally, the various deposition conditions and the plasma treatment were used. Sensitivities of the ZnO sensor were measured in acetone vapor and air at 250 degree C. In conclusion, we suggested that the sensitivity of ZnO sensors for acetone strongly depends on the work function of the as-deposited or plasma treated nano structured ZnO thin films.

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Enhanced UV Photon-response of Tin Nano Cluster Loaded- laser Irradiated ZnO Thin film detector

MRS Proceedings ◽

10.1557/opl.2011.206 ◽

2011 ◽

Vol 1288 ◽

Author(s):

Rashmi Menon ◽

K. Sreenivas ◽

Vinay Gupta

Keyword(s):

Thin Film ◽

Thin Films ◽

Magnetron Sputtering ◽

Surface States ◽

Response Speed ◽

Rf Magnetron Sputtering ◽

Fast Response ◽

Zno Thin Films ◽

Zno Thin Film ◽

Photo Response

ABSTRACTZinc Oxide (ZnO), II-VI compound semiconductor, is a promising material for ultraviolet (UV) photon sensor applications due to its attractive properties such as good photoconductivity, ease processing at low temperatures and excellent radiation hardness. The rf magnetron sputtering is a suitable deposition technique due to better control over stoichiometry and deposition of uniform film. Studies have shown that the presence of surface defects in ZnO and subsequently their passivation are crucial for enhanced photo-response characteristics, and to obtain the fast response speed. Worldwide efforts are continuing to develop good quality ZnO thin films with novel design structures for realization of an efficient UV photon sensor. In the present work, UV photon sensor is fabricated using a ZnO thin films deposited by rf magnetron sputtering on the corning glass substrate. Photo-response, (Ion/Ioff) of as-grown ZnO film of thickness 100 nm is found to be 3×103 with response time of 90 ms for UV intensity of 140 μW/cm2 (λ = 365 nm). With irradiation on ZnO thin film by pulsed Nd:YAG laser (forth harmonics 266 nm), the sensitivity of the UV sensor is found to enhance. The photo-response increases after laser irradiation to 4x104 with a fast response speed of 35 ms and attributed to the change in surface states and the native defects in the ZnO thin film. Further, enhancement in the ultraviolet (UV) photo-response (8×104) of detector was observed after integrating the nano-scale islands of Sn metal on the surface of laser irradiated ZnO thin film.

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Effect of Deposition Time on Properties of Nanostructured ZnO Thin Films Deposited by RF Magnetron Sputtering

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.832.460 ◽

2013 ◽

Vol 832 ◽

pp. 460-465 ◽

Cited By ~ 4

Author(s):

Nor Diyana Md Sin ◽

M.H. Mamat ◽

M. Rusop

Keyword(s):

Thin Film ◽

Thin Films ◽

Optical Properties ◽

Magnetron Sputtering ◽

Deposition Time ◽

Rf Magnetron Sputtering ◽

Zno Thin Films ◽

Zno Thin Film ◽

Time Increase ◽

Nanostructured Thin Film

The effect of deposition time on properties of ZnO nanostructured thin film was investigated. The ZnO thin films were deposited at various times from 15~75 minutes. The ZnO thin film at 60 min deposition time shows the highest current density and high conductivity with 2.15x10-2 Scm-1. The optical properties of ZnO thin films show high transmittance with >80% at 380 nm to 1200 nm. The thickness of ZnO thin film increases linearly with deposition time. The size of ZnO thin films increase as the deposition time increase. Based from fesem images, the ZnO nanocolumnar structure was formed at 15 to 60 minutes deposition time while at 75 minutes the sample formed nanoflakes structure.

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Electrical Properties Dependence on Substrate Temperature of Sputtered ZnO Nanoparticles Thin Films on Teflon Substrates

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.795.403 ◽

2013 ◽

Vol 795 ◽

pp. 403-406 ◽

Cited By ~ 2

Author(s):

Nur Sa’adah Muhamad Sauki ◽

Sukreen Hana Herman ◽

Mohd Hanafi Ani ◽

Mohamad Rusop

Keyword(s):

Thin Film ◽

Thin Films ◽

Substrate Temperature ◽

Rf Magnetron Sputtering ◽

Zno Thin Films ◽

Zno Thin Film ◽

X Ray Diffraction ◽

X Ray ◽

Current Voltage

Zinc oxide (ZnO) thin films were deposited on teflon substrates by RF magnetron sputtering at different substrate temperature. The effect of substrate temperature on ZnO thin films electrical and structural properties were examined using current-voltage (I-V) measurement, and x-ray diffraction (XRD) It was found that the electrical conductivity and resistivity of the ZnO thin film deposited at 40°C was the highest and lowest intensity accordingly. This was supported by the crystalline quality of the films from the x-ray diffraction (XRD) results. The XRD pattern showed that the ZnO thin film deposited at 40°C has the highest intensity with the narrowest full-width-at-half-maximum indicating that the film has the highest quality compared to other thin film.

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Effects of Thermal Annealing on the Characteristics of High Frequency FBAR Devices

Coatings ◽

10.3390/coatings11040397 ◽

2021 ◽

Vol 11 (4) ◽

pp. 397

Author(s):

Yu-Chen Chang ◽

Ying-Chung Chen ◽

Bing-Rui Li ◽

Wei-Che Shih ◽

Jyun-Min Lin ◽

...

Keyword(s):

Thin Film ◽

Thin Films ◽

Thermal Annealing ◽

Electromechanical Coupling ◽

Zno Thin Films ◽

Electromechanical Coupling Coefficient ◽

Back Side ◽

Zno Thin Film ◽

Frequency Responses ◽

Sputtering System

In this study, piezoelectric zinc oxide (ZnO) thin film was deposited on the Pt/Ti/SiNx/Si substrate to construct the FBAR device. The Pt/Ti multilayers were deposited on SiNx/Si as the bottom electrode and the Al thin film was deposited on the ZnO piezoelectric layer as the top electrode by a DC sputtering system. The ZnO thin film was deposited onto the Pt thin film by a radio frequency (RF) magnetron sputtering system. The cavity on back side for acoustic reflection of the FBAR device was achieved by KOH solution and reactive ion etching (RIE) processes. The crystalline structures and surface morphologies of the films were analyzed by X-ray diffraction (XRD) and field emission scanning electron microscope (FE-SEM). The optimized as-deposited ZnO thin films with preferred (002)-orientation were obtained under the sputtering power of 80 W and sputtering pressure of 20 mTorr. The crystalline characteristics of ZnO thin films and the frequency responses of the FBAR devices can be improved by using the rapid thermal annealing (RTA) process. The optimized annealing temperature and annealing time are 400 °C and 10 min, respectively. Finally, the FBAR devices with structure of Al/ZnO/Pt/Ti/SiNx/Si were fabricated. The frequency responses showed that the return loss of the FBAR device with RTA annealing was improved from −24.07 to −34.66 dB, and the electromechanical coupling coefficient (kt2) was improved from 1.73% to 3.02% with the resonance frequency of around 3.4 GHz.

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Effects of the Sputtering Time of AlN Buffer Layer on the Quality of ZnO Thin Films

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.881-883.1117 ◽

2014 ◽

Vol 881-883 ◽

pp. 1117-1121 ◽

Cited By ~ 1

Author(s):

Xiang Min Zhao

Keyword(s):

Thin Films ◽

Buffer Layer ◽

Rf Magnetron Sputtering ◽

Buffer Layers ◽

Zno Thin Films ◽

Zno Films ◽

Si Substrates ◽

Atomic Force ◽

Structure Morphology ◽

Aln Buffer

ZnO thin films with different thickness (the sputtering time of AlN buffer layers was 0 min, 30 min,60 min, and 90 min, respectively) were prepared on Si substrates using radio frequency (RF) magnetron sputtering system.X-ray diffraction (XRD), atomic force microscope (AFM), Hall measurements setup (Hall) were used to analyze the structure, morphology and electrical properties of ZnO films.The results show that growth are still preferred (002) orientation of ZnO thin films with different sputtering time of AlN buffer layer,and for the better growth of ZnO films, the optimal sputtering time is 60 min.

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Plasma Pre-Treatment of Polyethylene Terephthalate Substrate Influence on the Properties of ZnO Thin Film

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.895.41 ◽

2014 ◽

Vol 895 ◽

pp. 41-44

Author(s):

Seiw Yen Tho ◽

Kamarulazizi Ibrahim

Keyword(s):

Thin Film ◽

Thin Films ◽

Polyethylene Terephthalate ◽

Contact Angle Measurement ◽

Angle Measurement ◽

Zno Thin Films ◽

Zno Thin Film ◽

Water Contact ◽

Pre Treatment ◽

Pet Substrate

In this work, the influences of plasma pre-treatment on polyethylene terephthalate (PET) substrate to the properties of ZnO thin film have been carried out. ZnO thin films were successfully grown on PET substrate by spin coating method. In order to study the effects of plasma pre-treatment, a comparison of treated and untreated condition was employed. Water contact angle measurement had been carried out for PET wettability study prior to ZnO thin film coating. Morphology study of ZnO thin film was performed by scanning probe microscope (SPM). Besides, optical study of the ZnO thin film was done by using UV-vis spectrophotometer. All the measured results show that plasma pre-treatment of PET substrate plays an important role in enhancing the wettability of PET and optical properties of the ZnO thin films. In conclusion, pre-treatment of PET surface is essential to produce higher quality ZnO thin film on this particular substrate in which would pave the way for the integration of future devices.

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