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多种基底上溅射沉积ZnO薄膜的结构 总被引:4,自引:0,他引:4
在玻璃基底和四种硅基底上用反应式直流磁控溅射法制备了ZnO薄膜。用AES和XRD对薄膜结构和组分进行测试,结果表明,五种基底上生长的ZnO薄膜在不同程度上都具有优良的纵均匀性、明显的c轴择优取向和较高的结晶度,而硅基底上薄膜的结构普遍优于玻璃基底上沉积的薄膜。 相似文献
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ZnO线性电阻性能研究 总被引:8,自引:3,他引:5
ZnO线性电阻是一种新型的以ZnO为主的陶瓷电阻。本文研究了降温速度和烧结温度对ZnO线性电阻性能的影响,利用SEM、EPMA和XRD等技术研究其微观结构及晶相组成,根据提出的ZnO线性电阻的导电模型,对有关现象给予解释。 相似文献
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本文采用一次烧渗法制备出掺杂V2O3系PTC陶瓷的Ag-Zn-Ti电极,测量了电极的电学性能,采用差热—失重分析、XRD分析和电子探针X射线衍射显微分析等方法研究了电极的结构,同时对电极与陶瓷基体的接触状态进行了分析。研究结果表明:在电极与陶瓷基体间获得良好的欧姆接触,Zn和Ti固溶进入Ag晶格而形成固溶体,Zn对形成欧姆接触具有重要影响。 相似文献
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高能球磨法制备纳米晶Zn铁氧体 总被引:12,自引:0,他引:12
用高能球磨法制备了纳米晶Zn铁氧体。通过样品的Moessbauer谱及XRD谱的测定,研究了纳米晶的形成过程。结果表明:球磨的3hα-Fe2O3即与ZnO发生机械化学反应生成Zn铁氧体,这种反应是通过先形成α-Fe2O3-ZnO固溶体而进行的。制得的纳米晶铁氧体有一定的晶格畸变。 相似文献
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CaO—Al2O3—SiO2系白色微晶玻璃中的晶相及其演变 总被引:9,自引:0,他引:9
应用差热分析和X射线衍射谱研究了若干以ZnS为晶核剂的R2O-CaO-Al2O3-SiO2系白色微晶玻璃。根据差热结果确定了四个不同的晶化处理温度。晶化结果表明:本系统玻璃在较低温度下即开始晶体,且均以α-硅灰石为主晶相,这可用ZnS与α-硅灰石间晶核常数的匹配来解释。 相似文献
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超细肤色ZnO制备的新工艺研究 总被引:7,自引:0,他引:7
报道了在碱式碳酸锌热解过程中添加适量碳酸氢氨制得超肤色ZnO粉末的新方法,应用化学分析,XRD,TEM等方法对产品进行分析测试,结果表明,用该法合成的ZnO呈夫色,粒径小,近似球形,适用于化妆品,医药,颜料等领域。 相似文献
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采用射频磁控溅射法制备出了适用于HVPE-GaN厚膜生长的ZnO缓冲层,利用X射线衍射(XRD)和原子力显微镜(AFM)和光致发光(PL)等分析方法表征了ZnO缓冲层以及HVPE-GaN厚膜的晶体性能。实验结果表明,采用溅射功率为60W、氩气压强为2.0Pa、蓝宝石衬底为室温条件下的溅射工艺获得了(0002)单一取向、晶界清晰、晶粒尺寸均一的ZnO薄膜,以它为缓冲层获得的GaN厚膜XRD的(0002)衍射峰半高宽(FWHM)为265secarc,室温PL谱未见明显黄光发射带。 相似文献
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Continuous crystalline films of zinc oxide (ZnO) with thicknesses of 6–10 μm were obtained by electrochemical deposition from
aqueous zinc nitrate solutions on silicon substrates with a buffer nickel layer. X-ray diffraction measurements showed that
the polycrystalline films possess a hexagonal crystal lattice with predominant (0002) orientation. The obtained ZnO films
exhibit strong photoluminescence in the visible spectral range at room temperature. 相似文献
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K. Vijayalakshmi D. Gopalakrishna 《Journal of Materials Science: Materials in Electronics》2014,25(5):2253-2260
In this work, we report the influence of pyrolytic temperature on the properties of ZnO films deposited by a novel spray pyrolysis deposition route. XRD results revealed an improvement in crystal quality of the films with increase in growth temperature. The optical measurements of the films show a maximum transmittance of ~85 % and the band gap of ~3.5 eV. Photoluminescence spectra revealed that the UV emission peaks at 385 nm is improved with increase in growth temperature upto 300 °C, which corresponds to the increase of optical quality and decrease of Zn interstitial defect in the films. Gold ohmic contacts were evaporated on the optimized ZnO film prepared at the substrate temperature of 300 °C, and response of the film to different concentrations of hydrogen (150–500 ppm) at room temperature was investigated. The ZnO sensor showed significant sensitivity to hydrogen for concentration as low as 150 ppm at room temperature, and the sensor response was observed to increase with increase in hydrogen concentration. The increased sensitivity of the film was attributed to the large roughness of the film revealed from AFM analysis. The results ensure the application of our novel sensor, to detect H2 at low concentration and at room temperature. 相似文献
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ZnO thin films were prepared on quartz glass, Si (100), and sapphire (001) substrates by a chemical vapour transport (CVT) technique. During the growing processes, the source and substrate temperatures were maintained at 1000 °C and 600 °C, respectively. The scanning electron microscopy (SEM) and X-ray diffraction (XRD) measurements showed that the crystalline qualities of ZnO thin films were sensitively dependent on substrates. ZnO thin film deposited on sapphire substrate exhibited the best morphology with the largest crystallite size of more than 20 μm. Meanwhile, the XRD patterns showed that ZnO thin film deposited on sapphire substrate was strongly c-axis preferred-oriented with high crystalline quality. The optical properties of ZnO thin films were investigated by photoluminescence (PL) spectroscopy at room temperature (RT). The results suggested that the optical properties of ZnO thin films were highly influenced by their crystalline qualities and surface morphologies. 相似文献
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《Journal of Experimental Nanoscience》2013,8(3):281-293
Nanocomposites of polyvinylidene fluoride (PVDF) and nano-ZnO were prepared using the solution casting method for different concentrations of nano-ZnO and were characterised by X-ray diffraction and atomic force microscopy. Optical properties of these nanocomposites were determined by using UV-Vis absorption spectroscopy and Fourier transform infrared analysis. The variation of dielectric properties such as dielectric constant, dielectric loss and electric modulus of the hybrid films based on the content of ZnO studied for various microwave frequencies at room temperature showed that the dielectric constant of PVDF–ZnO hybrid films increased with increasing ZnO content at room temperature. 相似文献
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ZhiKun Zhang Jiming Bian Jingchang Sun Xiaowen Ma Yuxin Wang Chuanhui Cheng Yingmin Luo Hongzhu Liu 《Materials Research Bulletin》2012,47(9):2685-2688
ZnO thin films were deposited on graphite substrates by ultrasonic spray pyrolysis method. The effects of substrate temperature and film thickness on the crystalline structure, morphology, and optical properties of the as-grown ZnO films were investigated systemically. Results illustrated that dense ZnO films with hexagonal wurtzite structure were uniformly distributed on the substrate. Strong near-band edge ultraviolet (UV) emission peaks were observed in room temperature photoluminescence (PL) spectra for the samples prepared under optimized parameters, yet the usually observed defect related deep level emissions were nearly undetectable, indicating high optical quality ZnO films could be achieved via this easy process under optimal conditions. The successful growth of polycrystalline ZnO films on graphite offers the significant opportunity to be readily transferred onto any rigid or flexible foreign substrates, since the graphite substrates consist of weakly bonded layer structure. 相似文献
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不同衬底上低温生长的ZnO晶体薄膜的结构及光学性质比较 总被引:2,自引:0,他引:2
采用电子束反应蒸发方法,在单晶Si(001)及玻璃衬底上低温外延生长了沿c轴高度取向的单晶ZnO薄膜,并对沉积的ZnO晶体薄膜的结构和光学性质进行了分析比较。通过对ZnO薄膜的X射线衍射(XRD)分析及光致荧光激发谱(PLE)测量,研究了衬底材料结构特性、生长温度及反应气氛中充O 相似文献
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Jae Goo Kim Sang Mo Yang Jae Wook Lee Jung-Hoon Song Dojin Kim Hyo-Jong Lee 《Thin solid films》2010,519(1):223-227
We investigated the structural properties of Zn-polar ZnO films with low temperature (LT) ZnO and MgO buffer layers grown by plasma-assisted molecular beam epitaxy on (0001) c-Al2O3 substrates using X-ray diffraction and transmission electron microscopy (TEM). The effects of MgO buffer layer thickness and LT ZnO buffer layer thickness were also examined. The optimum thicknesses for better crystal quality were 8 and 40 nm. One-pair and two-pair LT ZnO/MgO buffer layers were employed, and the changes in the structural properties of the high-temperature (HT) ZnO films using such buffer layers were studied. Contrary to the general tendency of c-ZnO films, the HT ZnO films on the LT ZnO/MgO buffer layers showed higher full width at half maximum (FWHM) values for X-ray rocking curves (XRCs) with (0002) reflection than those with (101?1) reflection. Compared with the one-pair LT ZnO/MgO buffer layers, the FWHM values of (0002) XRCs markedly decreased, whereas those of (101?1) XRCs slightly increased due to the insertion of one more pair of LT ZnO/MgO buffer layers into the previous film with one-pair LT ZnO/MgO buffer layers. The cross-sectional TEM observations with the two-beam condition confirmed that the screw dislocation was the dominant threading dislocation type—a finding that agreed well with the XRC results. On the basis of the plan-view TEM observations, the densities of the total threading dislocations for the HT ZnO films with the one- and two-pair LT ZnO/MgO buffer layers were determined as 2.3 × 109 cm− 2 and 1.6 × 109 cm− 2, respectively. The results imply that the crystal quality of Zn-polar ZnO films can be improved by two-pair LT ZnO/MgO buffer layers, and types of threading dislocations can be modified by adjusting the buffer system. 相似文献
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本文采用直流磁控溅射法和多次沉积与掩膜技术,在n+Si(100)衬底上制备了一系列厚度不同的ZnO薄膜,表面镀Au的探针与ZnO/n+-Si构成了一系列ZnO层厚不同的Au/ZnO/n+-Si薄膜压敏电阻器.利用X射线衍射确定沉积的ZnO薄膜为高度c轴(0002)取向的晶体薄膜,利用紫外-可见透射光谱对沉积的ZnO薄膜... 相似文献
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Jun ZOU Shengming ZHOU Jun XU 《材料科学技术学报》2006,22(3):333-335
About φ45 mm LiAlO2 single crystal was grown by Czochralski (Cz) technique. However, the full-width at half-maximum (FWHM) value was high to 116.9 arcsec. After three vapor transport equilibration (VTE) processes, we can obtain high-quality LiAlO2 slice with the FWHM value of 44.2 arcsec. ZnO films were fabricated on as-grown slices and after-VTE ones by pulsed laser deposition (PLD). It was found that ZnO films on the two slices have similar crystallinity, optical transmittance and optical band gap at room temperature. These results not only show that LAO substrate is suitable for ZnO growth, but also prove that the crystal quality of LAO substrate slightly affects the structural and optical properties of ZnO film. 相似文献