RESUMO
Mo-doped zinc oxide (ZnOâ¶Mo) films were deposited with direct current magnetron sputtering on quartz substrates at room temperature. The effects of Mo doping content on the crystal structure, surface microstructureï¼optical properties and plasmon characteristics of the ZnO films were investigated with X-ray diffraction(XRD),atomic force microscopy (AFM),Spectrophotometer and Raman spectrometer. The XRD pattern reveals that pure ZnO film exhibits good crystallization and c-axis oriented while heavy doping leads to increasing film defects. That results decline the film crystalline quality. When Mo doping content exceeds 3.93 Wt%, the ZnO films transform c-axis oriented into amorphous. The AFM pattern indicates that the surface of amorphous MZO film is extraordinarily flat. The Rq is 498 pm. The transmittance spectra reveal that all samples have an average transmittance of 80% in the visible light range. The optical band gap energy (Eg) increases from 3.28 to 3.60 eV as the Mo doping content increase. The absorbance spectrum indicates that ZnO surface plasmon resonance absorbance perk moves to short-wavelength as the Mo doping content increase. The Raman spectrum suggests that heavy Mo doping make the Raman scattering intensity decrease significantly. This paper obtains amorphous ZnO thin film by Mo doping. That broadens the application field of ZnO thin film materials. Meanwhile, we study the effect of Mo doping concentration on ZnO thin films surface plasmon, which provides important reference value for the preparation of oxidized zinc base photonic devices.
RESUMO
Surface-enhanced Raman Spectroscopy (SERS) was a rapid non-destructive testing. It was based on detecting molecule vibrational spectrum which was adsorbed on the metallic surface. Now it was widely used in surface adsorption, electrochemical catalysis, sensors, bio-medical testing, trace amount analysis and other fields. In our experiment, copper metallic films were deposited 50 nm on BK7 glass substrates by direct current magnetron sputtering. And then the films were employed for the Ar ion beam etching modification. The structure, morphology and optical properties was characterized by X-ray diffraction (XRD), Atomic Force Microscope (AFM), spectrophotometer and Raman spectroscopy. In the XRD graph, the peak value of modify copper film were the same with the untreated film. So the structure of copper film was not change. With increasing the power of Ar ion, the surface roughness was changed, and scattered spectrum intensity was increased by surface roughness added. With Rhodamine B (Rh B) as a probe molecule, Raman scattered spectrum was detected on modify copper film. Compared with the different samples, we can find the Raman signal was enhanced by surface roughness added. It will have some value on study the principles of SERS.
RESUMO
A low cost and less complicated expansion approach of wavelength responses with a Lumogen phosphor coating was adopted, as they increased the quantum efficiency of CCD and CMOS detectors in ultra-violet by absorbing UV light and then re emitting visible light. In this paper, the sensitivity enhancement of fluorescence coatings was studied by adding an anti-reflection film or barrier film to reduce the loss of the scattering and reflection on the incident interface. The Lumogen and MgF2/Lumogen film were deposited on quartz glasses by physical vacuum deposition. The surface morphology, transmittance spectrum, reflectance spectrum and fluorescence emission spectrum were obtained by atomic force microscope (AFM), spectrophotometer and fluorescence spectrometer, respectively. The results indicated that MgF2 film had obvious positive effect on reducing scattering and reflection loss in 500-700 nm, and enhancing the absorption of Lumogen coating in ultraviolet spectrum. Meanwhile, the fluorescent emission intensity had a substantial increase by smoothing the film surface and thus reducing the light scattering. At the same time, the MgF2 layer could protect Lumogen coating from damaging and contamination, which give a prolong lifetime of the UV-responsive CCD sensors with fluorescent coatings.
RESUMO
In the present paper, the methods of spin-coating and physical vapor deposition (PVD) were researched to prepare the coronene film for UV-CCD, and their properties were characterized and compared with each other. The results of the experiment show that the process of spin-coating is relatively simple, which takes advantage of materials and retains the inherent crystal structure of coronene. However, the roughness of the film is a little more than that of PVD method; the film prepared by PVD method can absorb ultraviolet more effectively and then emits fluorescence with more intensity. Compared with the method of spin-coating, the surface of PVD film is more smoothly, and the process of thermal evaporation changes the crystal structure of coronene and forms another new crystalline state according to the XRD graph. While the whole process of PVD is morecomplex and it needs larger cost of production than spin-coating method. Besides, the comparison research work provided theoretical direction for preparing the photoluminescence down-conversion film under different requirements, such as fluorescence intensity, surface roughness and cost of production.
