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41.
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In this work,(-201) β-Ga_2O_3 films are grown on GaN substrate by metal organic chemical vapor deposition(MOCVD). It is revealed that the β-Ga_2O_3 film grown on GaN possesses superior crystal quality, material homogeneity and surface morphology than the results of common heteroepitaxial β-Ga_2O_3 film based on sapphire substrate. Further, the relevance between the crystal quality of epitaxial β-Ga_2O_3 film and the β-Ga_2O_3/GaN interface behavior is investigated. Transmission electron microscopy result indicates that the interface atom refactoring phenomenon is beneficial to relieve the mismatch strain and improve the crystal quality of subsequent β-Ga_2O_3 film. Moreover, the energy band structure of β-Ga_2O_3/GaN heterostructure grown by MOCVD is investigated by X-ray photoelectron spectroscopy and a large conduction band offset of 0.89 eV is obtained. The results in this work not only convincingly demonstrate the advantages of β-Ga_2O_3 films grown on GaN substrate, but also show the great application potential of MOCVD β-Ga_2O_3/GaN heterostructures in microelectronic applications. 相似文献
43.
Belyaev B. A. Tyurnev V. V. Voloshin A. S. Leksikov An. A. Galeev R. G. Shabanov V. F. 《Doklady Physics》2020,65(9):343-348
Doklady Physics - The design of a multilayer bandpass filter has been investigated, in which each of the half-wavelength resonators consists of two dielectric layers with outer strip conductor... 相似文献
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通过高温固相法制备Na2GdPO4F2:Tb3+绿色荧光粉,并利用X射线粉末衍射(XRD)和阴极射线光谱分别对其物相、阴极射线发光性能进行研究.结果表明,Tb3+作为绿色发光中心进入到Na2Gd2PO4F2的晶格中取代Gd3+的格位,在低电子束(0.5~5 kV)激发下主要表现出Tb3+的特征跃迁(5D3.4→7FJ,J=6~2),其中以5D4→7F5跃迁(546 nn)为主.样品Na2Gd0.95Tb0.05PO4F2在阴极射线激发下的色坐标为(0.240 3,0.438 6).随着电压、电流和掺杂量的增加,荧光粉的发光强度逐渐提高,其中,最佳的样品为Na2Gd0.9Tb0.1PO4F2. 相似文献
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Single crystalline GaN nanoribbons were synthesized through nitriding Ga2O3 thin films deposited on sapphire (0001) substrates by radio frequency magnetron sputtering. The component and structure of nanoribbons were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray (EDX), transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM). The flat and smooth ribbon-like nanostructures are high quality single crystalline hexagonal wurtzite GaN. The thickness and width-to-thickness ratio of the grown GaN nanoribbons are in the range of 8-15 nm and ∼5-10, respectively. 相似文献
49.
A noninterferometric optical fiber add-drop channel filter based on a mismatched twin-core photosensitive-cladding fiber and long-period fiber grating is demonstrated. With assistance from the fiber grating, co-directional spectrally selective cross coupling between the two cores can be realized with an efficiency of 90%. 相似文献
50.
Ji-Tae Hong Hyunwoong Seo Dong-Gil Lee Jin-Ju Jang Tae-Pung An Hee-Je Kim 《Journal of Electrostatics》2010,68(3):205-211
The dye coloring process on a nano-porous TiO2 thin film for DSSCs was studied using an electrostatic spraying (ESS) method. In this study, dye coating experiments were performed using homemade ESS equipment. The coating patterns on the TiO2 thin film are changed by adjusting the applied voltages of the ESS system. The geometry of the coating patterns is observed by a charge-coupled device (CCD) camera. The TiO2 thin film is fabricated by controlling the electric field which allows a uniform color distribution to be obtained with a high dyeing capacity. The colored TiO2 thin films are compared with those obtained using a conventional immersed dye solution by means of an UV–vis spectrometer. The performance of this novel coloring process was confirmed by measuring I–V curve characteristics. 相似文献