- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Detection of NH<SUB>3</SUB> Using ZnO Thin Film Sensor Deposited on Si/SiO<SUB>2</SUB> Substrate Derived by RF Magnetron Sputtering
摘要： This paper reports the research results of Zinc Oxide (ZnO) thin film gas sensor which is able to detect low concentration of ammonia gas (NH3). Pure ZnO layer is deposited on Si/SiO2 substrate at room temperature by RF magnetron sputtering technique. Pt micro-heater, platinum resistance thermometer (PRT) and gold electrodes are also fabricated along with ZnO thin film to make a complete NH3 sensor device and the fabrication process is discussed in detail in this manuscript. The deposited ZnO thin film is annealed at different temperatures and the effect of annealing temperature on the properties of ZnO thin film is analyzed by using various characterization techniques such as surface profilometer, XRD, SEM, EDX, etc. A measurement set-up is established for the measurements of various sensor parameters. An operating temperature is optimized for the NH3 gas sensor to enhance the sensitivity of the device. The optimized operating temperature is achieved and measured by Pt heater and PRT, respectively. The measurements are also performed for Pt micro-heater and PRT to calibrate the temperature with respect to heater current. Finally, the gas sensing measurements are performed in the range of small NH3 concentration (below 10 ppm) and the results confirm very good sensitivity even in very small NH3 concentration.
关键词： NH3 Gas,Thin Film,Pt Microheater,NH3 Gas Sensor,RF Sputtering,ZnO
更新于2025-09-23 15:22:29
-
The Size Effect of Exfoliated MoS <sub/>2</sub> Based Thin Film Humidity Sensor
摘要： Layered two-dimensional nanomaterials such as MoS2 show great potential for sensor application owing to their distinct nature that most atoms are surface atoms. The difficult in mass production of exfoliated MoS2 hinders its practical application. In this study, we investigate the ultrasound assisted liquid method to efficiently exfoliate MoS2 into nanosheets and nanoparticles. The dependence of ultrasonic dosing, e.g., ultrasonic time, on the morphology and yield of final products are studied. The exfoliated MoS2 nanomaterials are fabricated into thin film sensors and examined with humidity gas. The sensors exhibit excellent and quick response toward humidity gas. We find the sensor prepared with longer ultrasonic treatment presents higher response owing to that the longer ultrasonic irradiation exposes more active edge sites.
关键词： Exfoliation,Humidity Sensor,MoS2,Size Effect,Thin Film
更新于2025-09-23 15:22:29
-
Non-Evaporable Getter (NEG) Coating Using Titanium and Palladium Vacuum Sublimation
摘要： We have developed a new non-evaporable getter (NEG) coating using titanium and palladium vacuum sublimation. The inner wall of the test chamber was coated with a 1-μm Ti thin film using the Ti sublimation pumps under a vacuum of 6.5×10?? Pa (Ti-coated chamber). This chamber was then coated with a 10-nm Pd thin film using the Pd sublimation filament under a vacuum of 2.4×10?? Pa (Pd/Ti-coated chamber). The uncoated, Ti-coated, and Pd/Ti-coated chambers were baked for 6 h at a maximum temperature of 185°C. Five hours after closing the valve, the pressures in the Pd/Ti-coated chamber were about 1.4×10?? Pa even after six heating–venting cycles. The relatively low activation temperature was attributed to the low concentration of oxygen in the Pd/Ti thin films. The Pd/Ti coating can be used for vacuum systems that are frequently vented.
关键词： non-evaporable getter,titanium,thin film,palladium,vacuum
更新于2025-09-23 15:22:29
-
44.2: <i>Invited Paper:</i> Printed Polymer TFTs Towards Low-Cost Backplane Production
摘要： We present Merck’s new formulation and material developments enabling high-volume and high-throughput printing techniques to be used for cost-effective electronic circuitry and backplane production. Performance at TFT array level in excess of 2 cm2/Vs, comparable to spin coating is demonstrated at Gen1 scale and 50 ppi resolution, using a hybrid combination of conventional lithographic steps and direct gravure printing.
关键词： active-matrix backplane,Organic semiconductors,gravure,printed thin-film transistors
更新于2025-09-23 15:22:29
-
Effects of yttrium doping on the electrical performances and stability of ZnO thin-film transistors
摘要： In this paper, we have investigated the effects of yttrium (Y) doping on the electrical performance and stability of ZnO thin film transistors (TFTs). Here, Y-doped ZnO TFTs were fabricated by using radio frequency magnetron sputtering at 150 °C. As a result, the 1% Y-doped ZnO TFT exhibits a small threshold voltage shifts of 2.5 V under positive bias stress and ?2.8 V under negative bias stress as well as desirable device performance with field effect mobility of 9.8 cm2/V s, a subthreshold swing of 320 mV/decade and on/off current ratio of 107, respectively. Based on the XPS analysis and electrical characterizations, the improvement in stability and electrical properties of ZnO TFTs were attributed to the appropriate Y doping concentration, which not only could control the carrier concentration and broaden the band gap of ZnO film, but also suppress the oxygen vacancy defects and passivate the trap density at the SiO2/ZnO interfaces. Consequently, the high stability and excellent electrical performances of Y-doped ZnO TFTs show great potential for use in flat panel displays.
关键词： Doping,Zinc oxide (ZnO),Thin film transistors (TFTs),Bias stress stability
更新于2025-09-23 15:22:29
-
Quantifying Double-Layer Potentials at Liquid–Gas Interfaces from Vibrational Sum-Frequency Generation
摘要： Vibrational sum-frequency generation (SFG) spectroscopy is demonstrated as a fast method to quantify variations of the electric double-layer potential ?0 at liquid?gas interfaces. For this, mixed solutions of nonionic tetraethyleneglycol-monodecylether (C10E4) and cationic hexadecyltrimethylammonium bromide (C16TAB) surfactants were investigated using SFG spectroscopy and a thin-film pressure balance (TFPB). Derjaguin?Landau?Verwey?Overbeek analysis of disjoining pressure isotherms obtained with the TFPB technique provides complementary information on ?0, which we apply to validate the results from SFG spectroscopy. By using a single ?0 value, we can disentangle χ(2) and χ(3) contributions to the O?H stretching modes of interfacial water molecules in the SFG spectra. Having established the latter, we show that unknown double-layer potentials at the liquid?gas interface from solutions with different C16TAB/C10E4 mixing ratios can be obtained from an analysis of SFG spectra and are in excellent agreement with the complementary results from the TFPB technique.
关键词： disjoining pressure,Vibrational sum-frequency generation,electric double-layer potential,thin-film pressure balance,liquid?gas interfaces,surfactants
更新于2025-09-23 15:22:29
-
Bendable Single Crystal Silicon Nanomembrane Thin Film Transistors with Improved Low-Temperature Processed Metal/n-Si Ohmic Contact by Inserting TiO2 Interlayer
摘要： Bendable single crystal silicon nanomembrane thin film transistors (SiNMs TFTs), employing a simple method which can improve the metal/n-Silicon (Si) contact characteristics by inserting the titanium dioxide (TiO2) interlayer deposited by atomic layer deposition (ALD) at a low temperature (90 °C), are fabricated on ITO/PET flexible substrates. Current-voltage characteristics of titanium (Ti)/insertion layer (IL)/n-Si structures demonstrates that they are typically ohmic contacts. X-ray photoelectron spectroscopy (XPS) results determines that TiO2 is oxygen-vacancies rich, which may dope TiO2 and contribute to a lower resistance. By inserting TiO2 between Ti and n-Si, Ids of bendable single crystal SiNMs TFTs increases 3–10 times than those without the TiO2 insertion layer. The fabricated bendable devices show superior flexible properties. The TFTs, whose electrical properties keeps almost unchanged in 800 cycles bending with a bending radius of 0.75 cm, obtains the durability in bending test. All of the results confirm that it is a promising method to insert the TiO2 interlayer for improving the Metal/n-Si ohmic contact in fabrication of bendable single crystal SiNMs TFTs.
关键词： ohmic contact,thin film transistor,single-crystal Si nanomembrane (Si NMs),TiO2 insertion layer
更新于2025-09-23 15:22:29
-
[IEEE 2018 IEEE International Conference on Semiconductor Electronics (ICSE) - Kuala Lumpur (2018.8.15-2018.8.17)] 2018 IEEE International Conference on Semiconductor Electronics (ICSE) - Effect of Different Metal Contact Distance and Light on Electrical Properties of Calcium Carbonate Thin Film
摘要： CaCO3 is an inorganic substance with low toxicity. Electrical properties of CaCO3 is rarely reported although it has promising potential as biosensor. Therefore it is our aim to provide information on CaCO3 electrical properties. This work described the effect of different distance of metal contact pad and also the effect of light to the electrical conductivity of CaCO3. CaCO3 thin film was prepared at 1.0M by gas diffusion method. From the results, the value of current is not affected by different distance of metal contact pad. Results showed conductivity of CaCO3 thin films were not affected by the presence of light. Therefore CaCO3 thin film conductivity is stable and suitable for wide application and further study such as for biosensor.
关键词： CaCO3 Thin Film,Concentration,CaCO3 Electrical Properties,Gas Diffusion,Metal Pad Distance
更新于2025-09-23 15:22:29
-
Optical response of heterogeneous polymer layers containing silver nanostructures
摘要： This work is focused on the study of the optical properties of silver nanostructures embedded in a polymer host matrix. The introduction of silver nanostructures in polymer thin films is assumed to result in layers having adaptable optical properties. Thin film layers with inclusions of differently shaped nanoparticles, such as nanospheres and nanoprisms, and of different sizes, are optically characterized. The nanoparticles are produced by a simple chemical synthesis at room temperature in water. The plasmonic resonance peaks of the different colloidal solutions range from 390 to 1300 nm. The non-absorbing, transparent polymer matrix poly(vinylpyrrolidone) (PVP) was chosen because of its suitable optical and chemical properties. The optical studies of the layers include spectrophotometry and spectroscopic ellipsometry measurements, which provide information about the reflection, transmission, absorption of the material as well as the complex optical indices, n and k. Finite difference time domain simulations of nanoparticles in thin film layers allow the visualization of the nanoparticle interactions or the electric field enhancement on and around the nanoparticles to complete the optical characterization. A simple analysis method is proposed to obtain the complex refractive index of nanospheres and nanoprisms in a polymer matrix.
关键词： nanospheres,thin film layers,plasmonic nanoparticles,nanoprisms,spectroscopic ellipsometry
更新于2025-09-23 15:22:29
-
Effect of substrate temperature on structural and thermoelectric properties of RF-magnetron sputtered SnSe thin film
摘要： SnSe is a potential thermoelectric material, but there are few reports about the thermoelectric properties of the film. In this work, SnSe thin films were deposited on glass substrates by RF magnetron sputtering from SnSe alloy target. The effect of substrate temperature on the structural and thermoelectric properties was investigated. It was found that the columnar grains and the surface roughness of the films increase with increasing the substrate temperature. The film deposited at 558 K exhibited a high crystalline quality and stoichiometric composition, which has a maximum power factor of 1.4 uWcm-1K-2 at 575 K. The results of this work demonstrate the importance of high substrate temperature to obtain high thermoelectric performance SnSe films.
关键词： SnSe thin film,sputtering,thermoelectric properties
更新于2025-09-23 15:22:29