scholarly journals Characteristics of Metal–Semiconductor–Metal Ultraviolet Photodetectors Based on Pure ZnO/Amorphous IGZO Thin-Film Structures

2021 ◽  
Vol 2021 ◽  
pp. 1-6
Author(s):  
Kin-Tak Lam ◽  
Sheng-Joue Young ◽  
Yen-Lin Chu ◽  
Chi-Nan Tsai ◽  
Tung-Te Chu ◽  
...  
Keyword(s):  
Thin Films ◽  
Zinc Oxide ◽  
Rf Magnetron Sputtering ◽  
Indium Gallium Zinc Oxide ◽  
Pure Zinc ◽  
Glass Substrates ◽  
Rejection Ratio ◽  
Light Region ◽  
Metal Semiconductor Metal ◽  
Dark Currents

In this study, metal–semiconductor–metal-structured ultraviolet (UV) photodetectors (PDs) based on pure zinc oxide (ZnO) and amorphous indium gallium zinc oxide (a-IGZO) thin films were fabricated and characterized. The ZnO seed layers were deposited on Corning glass substrates via a radio frequency (RF) magnetron sputtering technique. Results showed that under a 5 V applied bias; the dark currents of the pure ZnO and a-IGZO thin films were 0.112 pA and 2.85 nA, respectively. Meanwhile, the UV-to-visible rejection ratio of the pure ZnO and a-IGZO thin films were 14.33 and 256, respectively. Lastly, the PDs of thea-IGZO thin films had a lower leakage current and higher rejection ratio than that of the pure ZnO thin films from the UV to visible light region.

ANNEALING EFFECTS ON CONTACT PROPERTIES OF ALUMINUM DOPED ZINC OXIDE THIN FILMS

2002 ◽  
Vol 16 (01n02) ◽  
pp. 294-301
Author(s):  
KE BIN LOW ◽  
HAO GONG ◽  
ENG FONG CHOR
Keyword(s):  
Thin Films ◽  
Zinc Oxide ◽  
Structural Changes ◽  
Rf Magnetron Sputtering ◽  
Contact Resistivity ◽  
Glass Substrates ◽  
Specific Contact ◽  
Annealing Effects ◽  
Specific Contact Resistivity ◽  
Diffraction Patterns

Aluminum Zinc Oxide (AZO) thin films are grown on glass substrates by RF Magnetron Sputtering using a single target of zinc oxide (99 wt%) and aluminum oxide (1 wt%) with argon as the plasma. Photolithographic process is then performed on the films in order to obtain a Transmission Line Model structure (TLM) of the metal contact system, namely aluminum and gold. The specific contact resistivity, ρc, of these two metal-semiconductor systems, which will undergo different rapid thermal annealing (RTA) environment, are determined. X-Ray diffraction patterns for these samples are obtained to investigate phase formations or micro-structural changes so as to justify for the differences in specific contact resistivity obtained for these contact systems. The different RTA environment are simulated by purging either nitrogen or argon gas, with a pressure of 40 psi at a temperature of 400°C for 60 s; and annealing in vacuum (10-6 Torr) also at the same temperature and duration. One-dimensional TLM (1D-TLM) measurements are performed on the TLM structures to obtain the specific contact resistivity, ρc. Results show that aluminum contacts on AZO without RTA give the lowest ρc as compared to those in other environment, while gold contacts on AZO annealed in vacuum yield the lowest ρc. Adhesion of aluminum contacts on AZO is good even when subjected to ultrasonic bath test but not true for the case of gold contact, which adheres poorly on AZO films.

Micrographs and Optical Properties of Al-Doped ZnO Thin Films Deposited by Radio Frequency Magnetron Sputtering

2014 ◽  
Vol 924 ◽  
pp. 176-180
Author(s):  
Yuan Yuan Li ◽  
Zhen Chen ◽  
Shu Li Li ◽  
Xi Long Li ◽  
Geng Rong Chang ◽  
...  
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Magnetron Sputtering ◽  
Radio Frequency ◽  
Rf Magnetron Sputtering ◽  
Sem Images ◽  
Axis Orientation ◽  
Glass Substrates ◽  
Light Region ◽  
Doped Zno

The micrographs and optical properties of Al-doped ZnO (AZO) films deposited by radio frequency (RF) magnetron sputtering are presented in this paper. The AZO films termed as films I, II and III were sputtered on glass substrates heating at 300C, 400C and 500C, respectively. The micrographs, crystal structures and optical properties of AZO thin films were analyzed by using scanning electronic microscopy (SEM) images, X-ray diffraction (XRD) pattern, optical transmission and reflection spectra ranging from 350 to 1000 nm. As the substrate temperature increases to 500C, the film III exhibits a better flatness surface and a larger grain size of ~25nm with a stronger c-axis orientation. The film II has a high transmittance of greater than 92% in the visible light region. We also show that the films II and III have significant red-shift band gap ~3.00 and ~3.13eV, respectively, in comparison with that of the film I (3.31eV). This might be due to the increasing doped Al atoms which do not activate due to segregation at the grain boundaries.

scholarly journals The Characteristics of Aluminum-Gallium-Zinc-Oxide Ultraviolet Phototransistors by Co-Sputtering Method

Electronics ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 631
Author(s):  
Wei-Lun Huang ◽  
Sheng-Po Chang ◽  
Cheng-Hao Li ◽  
Shoou-Jinn Chang
Keyword(s):  
Zinc Oxide ◽  
Thin Film Transistors ◽  
High Performance ◽  
Wide Bandgap ◽  
Visible Light Region ◽  
Current Ratio ◽  
Rejection Ratio ◽  
Light Region ◽  
Sputtering Power ◽  
Solar Blind

In this thesis, Aluminum-Gallium-Zinc oxide (AGZO) photo thin film transistors (PTFTs) fabricated by the co-sputtered method are investigated. The transmittance and absorption show that AGZO is highly transparent across the visible light region, and the bandgap of AGZO can be tuned by varying the co-sputtering power. The AGZO TFT demonstrates high performance with a threshold voltage (VT) of 0.96 V, on/off current ratio of 1.01 × 107, and subthreshold swing (SS) of 0.33 V/dec. Besides, AGZO has potential for solar-blind applications because of its wide bandgap. The AGZO PTFT of this research can achieve a rejection ratio of 4.31 × 104 with proper sputtering power and a rising and falling time of 35.5 s and 51.5 s.

Dependence of Film Thickness on Properties of Al Doped ZnO Thin Films

2011 ◽  
Vol 194-196 ◽  
pp. 2305-2311
Author(s):  
Ying Ge Yang ◽  
Dong Mei Zeng ◽  
Hai Zhou ◽  
Wen Ran Feng ◽  
Shan Lu ◽  
...  
Keyword(s):  
Thin Films ◽  
Film Thickness ◽  
Electrical Parameter ◽  
Substrate Surface ◽  
Rf Magnetron Sputtering ◽  
Thickness Effect ◽  
Visible Range ◽  
Glass Substrates ◽  
Doped Zno

In this study high quality of Al doped ZnO (ZAO) thin films were prepared by RF magnetron sputtering on glass substrates at room temperature in order to study the thickness effect upon their structure, electrical and optical properties. XRD results show that the films are polycrystalline and with strongly preferred (002) orientation perpendicular to substrate surface whatever the thickness is. The crystallite size was calculated by Williamson-Hall method, while it increases as the film thickness increased. The lattice stress is mainly caused by the growth process. Hall measurements revealed electrical parameter very dependent upon thickness when the thickness of ZAO film is lower than 700 nm. The resistivity decreased and the carrier concentration and Hall mobility increases as the film thickness increased. When film thickness becomes larger, only a little change in the above properties was observed. All the films have high transmittance above 90% in visible range. Red shift of the absorption edge was observed as thickness increased. The optical energy bandgap decreased from 3.41eV to 3.30 eV with the increase of film thickness.

Study on Structural Properties of Gallium and Titanium Doped Zinc Oxide Films Deposited by Magnetron Sputtering

2014 ◽  
Vol 908 ◽  
pp. 124-128 ◽  
Author(s):  
S.B. Chen ◽  
Z.Y. Zhong
Keyword(s):  
Thin Films ◽  
Zinc Oxide ◽  
Magnetron Sputtering ◽  
Crystal Structures ◽  
X Ray Diffraction ◽  
Hexagonal Crystal ◽  
Working Pressure ◽  
Sintered Ceramic ◽  
Glass Substrates ◽  
Zinc Oxide Films

Thin films of transparent conducting gallium and titanium doped zinc oxide (GTZO) were prepared on glass substrates by magnetron sputtering technique using a sintered ceramic target. The microstructural properties of the deposited thin films were characterized with X-ray diffraction (XRD). The results demonstrated that the polycrystalline GTZO thin films consist of the hexagonal crystal structures with c-axis as the preferred growth orientation normal to the substrate, and that the working pressure significantly affects the crystal structures of the thin films. The GTZO thin film deposited at the working pressure of 0.4 Pa has the best crystallinity, the largest grain size and the lowest stress.

scholarly journals Structural and Optical Properties of Cobalt-Doped Zinc Oxide Thin Films Prepared By Spray Pyrolysis Technique

2010 ◽  
Vol 7 (1) ◽  
pp. 69-75
Author(s):  
Baghdad Science Journal
Keyword(s):  
Thin Films ◽  
Zinc Oxide ◽  
Optical Properties ◽  
Spray Pyrolysis ◽  
Spray Pyrolysis Technique ◽  
Texture Coefficient ◽  
Hexagonal Structure ◽  
Structural And Optical Properties ◽  
Lattice Constants ◽  
Glass Substrates

Undoped and Co-doped zinc oxide (CZO) thin films have been prepared by spray pyrolysis technique using solution of zinc acetate and cobalt chloride. The effect of Co dopants on structural and optical properties has been investigated. The films were found to exhibit maximum transmittance (~90%) and low absorbance. The structural properties of the deposited films were examined by x-ray diffraction (XRD). These films, deposited on glass substrates at (400? C), have a polycrystalline texture with a wurtzite hexagonal structure, and the grain size was decreased with increasing Co concentration, and no change was observed in lattice constants while the optical band gap decreased from (3.18-3.02) eV for direct allowed transition. Other parameters such as Texture Coefficient (Tc), dislocation density (?) and number of crystals (M) were also calculated .

scholarly journals Residual Oxygen Effects on the Properties of MoS2 Thin Films Deposited at Different Temperatures by Magnetron Sputtering

Crystals ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1183
Author(s):  
Peiyu Wang ◽  
Xin Wang ◽  
Fengyin Tan ◽  
Ronghua Zhang
Keyword(s):  
Thin Films ◽  
Electrical Properties ◽  
Magnetron Sputtering ◽  
Deposition Rate ◽  
Deposition Temperature ◽  
Energy Dispersive Spectrometer ◽  
Rf Magnetron Sputtering ◽  
Glass Substrates ◽  
Different Temperatures ◽  
Oxygen Atoms

Molybdenum disulfide (MoS2) thin films were deposited at different temperatures (150 °C, 225 °C, 300 °C, 375 °C, and 450 °C) on quartz glass substrates and silicon substrates using the RF magnetron sputtering method. The influence of deposition temperature on the structural, optical, electrical properties and deposition rate of the obtained thin films was investigated by X-ray diffraction (XRD), Energy Dispersive Spectrometer (EDS), Raman, absorption and transmission spectroscopies, a resistivity-measuring instrument with the four-probe method, and a step profiler. It was found that the MoS2 thin films deposited at the temperatures of 150 °C, 225 °C, and 300 °C were of polycrystalline with a (101) preferred orientation. With increasing deposition temperatures from 150 °C to 300 °C, the crystallization quality of the MoS2 thin films was improved, the Raman vibrational modes were strengthened, the deposition rate decreased, and the optical transmission and bandgap increased. When the deposition temperature increased to above 375 °C, the molecular atoms were partially combined with oxygen atoms to form MoO3 thin film, which caused significant changes in the structural, optical, and electrical properties of the obtained thin films. Therefore, it was necessary to control the deposition temperature and reduce the contamination of oxygen atoms throughout the magnetron sputtering process.

scholarly journals Optical Properties of Sn Doped ZnO Thin Film Prepared Using Sol-Gel Method for Optical Limiting Application

2021 ◽  
Vol 24 (3) ◽  
pp. 38-42
Author(s):  
Marwa Mudfer Alqaisi ◽  
◽  
Alla J. Ghazai ◽  
Keyword(s):  
Thin Films ◽  
Zinc Oxide ◽  
Optical Properties ◽  
Sol Gel ◽  
Visible Region ◽  
Optical Limiting ◽  
Pure Zinc ◽  
Gel Method ◽  
Sol Gel Method ◽  
Doped Zno

In this work, pure Zinc oxide and tin doped Zinc oxide thin films nanoparticles with various volume concentrations of 2, 4, 6, and 8V/V% were prepared by using the sol-gel method. The optical properties were investigated by using UV-Visible spectroscope, and the value exhibits the direct allowed transition. The average of transmittance was around ~(17-23) %in visible region. The optical energy band gap was calculated with wavelength (300-900) nm for pure ZnO and Sn doped ZnO thin films which decreases with increasing concentration from 3.4 eV to 3.1 eV respectively and red shift. The real dielectric(εr) and the imaginary dielectric εiare the same behavior of the refractive index(n) the extinction coefficient (k) respectively. The optical limiting properties were studied by using an SDL laser with a wavelength of 235 nm. ZnO and doping thin films an found efficient as optic limiting and depend on the concentration of the all samples.

Zinc Oxide Thin Films Grown on Nanostructured Al Thin Layer/Glass Substrate by RF Magnetron Sputtering

2011 ◽  
Vol 239-242 ◽  
pp. 777-780
Author(s):  
Ting Zhi Liu ◽  
Shu Wang Duo ◽  
C Y Hu ◽  
C B Li
Keyword(s):  
Thin Films ◽  
Zinc Oxide ◽  
Magnetron Sputtering ◽  
Thin Layer ◽  
Glass Substrate ◽  
Rf Magnetron Sputtering ◽  
Zno Films ◽  
Zno Film ◽  
Substrate Roughness ◽  
Axis Orientation

ZnO films were deposited on nanostructured Al (n-Al) /glass substrate by RF magnetron sputtering. The results shows that the relation (I (002) /I (100) ≈ I annealed (002)/I annealed (100) ≈1.1) shows the rough n-Al surface is suitable for the growth of a-axis orientation. Meanwhile, the influences of substrate roughness, crystallinity and (101) plane of ZnO film deposited on n-Al layer have been discussed. XPS implies more oxygen atoms are bound to Aluminum atoms, which result in the increase of high metallic Zn in the film.

Sign in / Sign up

Export Citation Format

Share Document