- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
NO<sub>2</sub> gas sensing performance enhancement based on reduced graphene oxide decorated V<sub>2</sub>O<sub>5</sub> thin film
摘要： Here, we demonstrate the improved NO2 gas sensing properties based on reduced graphene oxide (rGO) decorated V2O5 thin film. Excluding the DC sputtered grown V2O5 thin film, rGO was spread over V2O5 thin film by drop cast method. The formation of several p-n heterojunctions is greatly affected by the current-voltage relation of rGO decorated V2O5 thin film due to p-type and n-type nature of rGO and V2O5, respectively. Initially with rGO decoration on V2O5 thin film, current decreases in comparison to V2O5 thin film, whereas depositing rGO film on glass substrate, current increases drastically. Among all sensors, only rGO decorated V2O5 sensor revealed maximum NO2 gas sensing response for 100 ppm at 150°C, and helped achieve approximately 61% times more response than the V2O5 sensor. An elaborated mechanism for an extremely high sensing response is attributed to the formation and modulation of p-n heterojunction at the interface of rGO and V2O5. In addition, the presence of active sites like oxygenous functional groups on rGO surface also enhances the sensing response. On that account, the sensor based on rGO decorated V2O5 thin film is highly suitable for the purpose of NO2 gas sensing. This enables timely detection of the gas, further prevent the ecosystem from its harmful effects.
关键词： NO2 gas,relative response,DC sputtering,p-n heterojunction,rGO decorated V2O5 thin film
更新于2025-09-19 17:15:36
-
Growth of Atomic Layer Deposited Ruthenium and Its Optical Properties at Short Wavelengths Using Ru(EtCp)2 and Oxygen
摘要： High-density ruthenium (Ru) thin films were deposited using Ru(EtCp)2 (bis(ethylcyclopentadienyl)ruthenium) and oxygen by thermal atomic layer deposition (ALD) and compared to magnetron sputtered (MS) Ru coatings. The ALD Ru film growth and surface roughness show a significant temperature dependence. At temperatures below 200 °C, no deposition was observed on silicon and fused silica substrates. With increasing deposition temperature, the nucleation of Ru starts and leads eventually to fully closed, polycrystalline coatings. The formation of blisters starts at temperatures above 275 °C because of poor adhesion properties, which results in a high surface roughness. The optimum deposition temperature is 250 °C in our tool and leads to rather smooth film surfaces, with roughness values of approximately 3 nm. The ALD Ru thin films have similar morphology compared with MS coatings, e.g., hexagonal polycrystalline structure and high density. Discrepancies of the optical properties can be explained by the higher roughness of ALD films compared to MS coatings. To use ALD Ru for optical applications at short wavelengths (λ = 2–50 nm), further improvement of their film quality is required.
关键词： optical properties,sputtering,structural properties,XUV,ruthenium,soft X-ray,thin film,atomic layer deposition
更新于2025-09-19 17:15:36
-
Nanostructure and Optical Property Investigations of SrTiO3 Films Deposited by Magnetron Sputtering
摘要： Strontium titanate thin films were deposited on a silicon substrate by radio-frequency magnetron sputtering. The structural and optical properties of these films were characterized by X-ray diffraction, high-resolution transmission electron microscopy, X-ray photoelectron spectroscopy, and spectroscopic ellipsometry, respectively. After annealing at 600–800 °C, the as-deposited films changed from amorphous to polycrystalline. It was found that an amorphous interfacial layer appeared between the SrTiO3 layer and Si substrate in each as-deposited film, which grew thicker after annealing. The optical parameters of the SrTiO3 film samples were acquired from ellipsometry spectra by fitting with a Lorentz oscillator model. Moreover, we found that the band gap energy of the samples diminished after thermal treatment.
关键词： thermal treatment,strontium titanate film,optical properties,magnetron sputtering
更新于2025-09-19 17:15:36
-
Preparation and magnetic properties for FeSe <sub/><i>x</i> </sub> /Bi <sub/>2</sub> Se <sub/>3</sub> bilayer films on silicon substrates by RF magnetron sputtering
摘要： FeSex/Bi2Se3 bilayer thin films were grown by RF magnetron sputtering on silicon substrates with different thicknesses of Bi2Se3 and the structural, morphological and magnetic properties were investigated. FeSex/Bi2Se3 bilayer films had Bi2Se3 crystallites oriented with c-axis perpendicular to the film plane, and exhibited weak ferromagnetism at low temperature due to the ferromagnetic FeSe2. The thickness of Bi2Se3 layer affected both crystalline structure of Fe–Se layer and the magnetic property.
关键词： magnetic phase,RF magnetron sputtering,paramagnetism,Topological insulator,bilayer films
更新于2025-09-19 17:15:36
-
Photoluminescence Properties of Yb and Ag Co-Doped Ta<sub>2</sub>O<sub>5</sub> Thin Films
摘要： We prepared ytterbium and silver co-doped tantalum-oxide (Ta2O5:Yb,Ag) thin films using a simple co-sputtering method and evaluated photoluminescence (PL) properties of the films after annealing. We found that a PL peak at a wavelength of 980 nm due to Yb3+ can be strongly enhanced by Ag doping. From X-ray diffraction measurements, we found that Ag2Ta8O21 and orthorhombic Ta2O5 crystalline phases are very important in order to enhance the 980-nm peak observed from our Ta2O5:Yb,Ag thin films. Because of the human-body transmittability of the 980-nm wavelength, such films are applicable to a novel real-time X-ray dosimeter system.
关键词： Yb,Ag,co-sputtering,Ta2O5,photoluminescence,X-ray diffraction
更新于2025-09-19 17:15:36
-
Thermal Stability of WB2 and W–B–N Films Deposited by Magnetron Sputtering
摘要： The work is mainly to study the thermal stability including the phase stability, microstructure and tribo-mechanical properties of the AlB2-type WB2 and W–B–N (5.6 at.% N) films annealed in vacuum at various temperatures, which are deposited on Si and GY8 substrates by magnetron sputtering. For the WB2 and W–B–N films deposited on Si wafers, as the annealing temperature increases from 700 to 1000 °C, a-WB (700 °C) and Mo2B5-type WB2 (1000 °C) are successively observed in the AlB2-type WB2 films, which show many cracks at the temperature ≥ 800 °C resulting in the performance failure; by contrast, only slight α-WB is observed at 1000 °C in the W–B–N films due to the stabilization effect of a-BN phase, and the hardness increases to 34.1 GPa first due to the improved crystallinity and then decreases to 31.5 GPa ascribed to the formation of α-WB. For the WB2 and the W–B–N films deposited on WC–Co substrates, both the WB2 and W–B–N films react with the YG8 (WC–Co) substrates leading to the formation of CoWB, CoW2B2 and CoW3B3 with the annealing temperature increasing to 900 °C; a large number of linear cracks occur on the surface of these two films annealed at ≥ 800 °C leading to the film failure; after vacuum annealing at 700 °C, the friction performance of the W–B–N films is higher than that of the deposited W–B–N films, while the wear resistance of the WB2 films shows a slight decrease compared with that of the deposited WB2 films.
关键词： AlB2-type WB2 films,Thermal stability,W–B–N films,Magnetron sputtering,Mechanical properties
更新于2025-09-19 17:15:36
-
Sputtered ZnSnO buffer layers for kesterite solar cells
摘要： Replacing the CdS buffer layer with a ZnSnO one in Cu2ZnSnS4-based solar cells allows both to improve the device performances and to avoid using toxic Cd. Additionally, using a sputtered buffer layer is a major asset for solar cells fabricated by physical vapor deposition processes. In this study, ZnSnO layers are deposited by sputtering of a single metal-oxide target. Structural and optical properties of the layers deposited on Si or glass are first described. The possibility of modifying the ZnSnO metallic composition by adjusting the deposition power is demonstrated. Attempts to improve the optoelectronic properties of the ZnSnO layers with Ar:O2 or Ar:SF6 reactive sputtering are shown as well. These ZnSnO buffer layers are transferred in Mo/CZTS/ZnSnO/ZnO:Al solar cells. After post-deposition thermal treatment and optimization of the deposition condition (notably with the use of Ar:O2 or Ar:SF6 reactive sputtering), a solar cells with a power conversion efficiency of 5.2% is demonstrated. It is 0.6% absolute higher than the reference solar cell with a CdS buffer layer. To avoid absorber damaging and achieve high performances, deposition power must be as low as possible. A two stages sputtering process is used to conciliate both the absorber surface preservation and a reasonable deposition time. Last, photovoltaic properties of optimized CZTS- and CZTSe-based solar cells with ZnSnO buffer layers are compared.
关键词： Cu2ZnSnS4,ZnSnO buffer layer,Cd-free devices,sputtering,reactive sputtering,Kesterite solar cells
更新于2025-09-19 17:13:59
-
Spark plasma sintering of Sb2Se3 sputtering target towards highly efficient thin film solar cells
摘要： Antimony selenide (Sb2Se3) is a potential absorber material for environment-friendly and cost-efficiently photovoltaics due to its material advantages and superior optoelectronic properties. In this work, we proposed a facile and versatile method of ball milling followed with spark plasma sintering (SPS) to prepare high-quality Sb2Se3 sputtering target. Then the highly crystalline Sb2Se3 thin film consisted of large crystal grains can be prepared by using radio frequency (RF) magnetron sputtering with an additional post-selenization heat treatment. An efficient substrate structured Sb2Se3 thin film solar cell with configuration of Mo/Sb2Se3/CdS/ITO/Ag was fabricated and a champion device with highly interesting power conversion efficiency (PCE) of 5.08% has been achieved. Superior device performances are closely related to the Sb2Se3 absorber layer with benign growth orientation and the Sb2Se3/CdS heterojunction interface with smooth contact, which induced less recombination loss. The combined features of homemade sputtering target and advantageous thin film preparation technology further demonstrated its attractive application potential in thin film photovoltaic scenarios.
关键词： Sb2Se3,Post-selenization,Sputtering target,Magnetron sputtering,Spark plasma sintering,Thin film solar cells
更新于2025-09-19 17:13:59
-
Investigation of structural and optoelectronic properties of n-MoS2/p-Si sandwiched heterojunction photodetector
摘要： Molybdenum disulphide (MoS2), a member of the transition metal dichalcogenides family has shown excellent optoelectronic properties with direct or indirect bandgaps in visible range as well as good absorption in its 2-dimensional (2D) form. In this work, a polycrystalline MoS2 thin film is fabricated by radio frequency magnetron sputtering. X-ray diffraction (XRD) analysis of the fabricated sample reveals two hexagonal structured peaks along the (100) and (110) planes, while energy-dispersive X-ray (EDX) spectroscopy confirms a non-stoichiometric MoS2 film with a thickness of 300 nm. Raman shifts are observed at the E1 2g and A1g phonon modes, located at 374.37 cm?1 and 407.75 cm?1 respectively. A sandwiched heterojunction photodetector with a SLG/n-MoS2/p-Si structure is fabricated and illuminated with violet light at 441 nm. The device exhibits significant optoelectronic properties at various laser powers at a 10 V bias voltage. The maximum value of the photocurrent is calculated as 0.79 μA, with the responsivity as 10.4 mAW?1 and detectivity of 6.74 × 109 Jones at an intensity of 0.004 mW/cm2. These results highlight the adaptability of the current technique that will help realize large-scale production as well as allow for the development of advanced optoelectronic devices.
关键词： Photodetectors,Thin films,RF sputtering,MoS2,Raman
更新于2025-09-19 17:13:59
-
All-sputtered CdTe solar cell activated with a novel method
摘要： CdTe thin film solar cells are usually fabricated depositing the absorber layer by Close Space Sublimation (CSS) and Vapor Transport Deposition (VTD), mainly due to the high deposition rate allowed by these techniques. However, most of the solar cell films can be deposited by sputtering, making to deposit also the CdTe by this technique attractive. Indeed, an all-sputtered solar cell could be deposited in one sequential chamber at a relatively low temperature and without breaking the vacuum, resulting in a sensible decrease in the production cost at the industrial level. Usually, treatments based on CdCl2, also known as activations, are applied to the CdTe solar cells to achieve high power conversion efficiency (PCE). However, it was observed that the usual activation methods could be aggressive for all-sputtered CdTe solar cells, damaging the films and resulting in low performance. In this work, we propose a novel activation method based on Nitrogen/Oxygen/CHCIF2 gas mixture, which is more suitable for this kind of device. Morphological, structural, optical and electrical properties were analyzed and compared to our CSS-CdCl2 baseline. A PCE of 12% was achieved for all-sputtered CdTe solar cells.
关键词： Sputtering,CdTe,Solar cells,Activation
更新于2025-09-19 17:13:59