共查询到19条相似文献,搜索用时 78 毫秒
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沉积气压对磁控溅射制备ZnO薄膜的结构与光学性能影响 总被引:2,自引:0,他引:2
采用CS-400型射频磁控溅射仪在Si(111)和石英基底上成功的制备了ZnO薄膜,分别用XRD、SEM、紫外-可见光分光光度计和荧光分光光度计表征样品的结构和光学性质.实验表明,采用射频磁控溅射制备的ZnO薄膜具有六角纤锌矿结构的(002)峰和(101)峰的两种取向.在沉积气压>1.0Pa时所制备的ZnO薄膜具有(002)择优取向,并且十分稳定.SEM图表明,ZnO薄膜颗粒大小较为均匀,晶粒尺寸随着气压升高而变小,沉积气压不同时,薄膜样品的生长方式有所差异.在400~1000nm范围内,可以看出除O.5Pa下制备的ZnO薄膜外,其余ZnO薄膜在可见光区域的平均透过率超过80%,吸收边在380nm附近,所对应的光学带隙约为3.23~3.27eV,并随着沉积气压上升而变大.ZnO薄膜的PL谱上观察到了392nm的近紫外峰和419nm的蓝峰;沉积气压对Zno薄膜的发光峰位和峰强有影响. 相似文献
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采用浸渍-提拉法制备聚苯乙烯微球(PS)模板,以醋酸锌(Zn(CH3COO)2·2H2O)、二乙醇胺(NH(C2H2OH)2)、乙醇和水等配制的前驱体溶胶填充PS模板间隙,经过干燥过程原位形成凝胶,最后通过煅烧除去PS微球模板得到有序规则排列的多孔ZnO薄膜。重点讨论了模板在溶胶中的浸渍时间、溶胶的浓度对有序多孔结构形成的影响.通过TG-DTA分析、 XRD、TEM、SEM、IR反射光谱和UV-VIS光谱对结构和性能进行了表征.结果表明, 用无皂聚合制备的PS直径约为400nm,IR反射光谱布拉格反射测定PS模板为fcc结构,平行于基底的密排面为(111),ZnO由无定形向纤锌矿转变温度是460℃,多孔薄膜的孔径约为 280nm,孔壁由晶粒直径约46nm的ZnO粒子构成,.透光率为60%,禁带宽度Eg约为3.24eV. 相似文献
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利用激光分子束外延方法(LMBE)在单晶Si(100)和玻璃基片上生长了ZnO薄膜.通过XRD谱、拉曼光谱和光致发光(PL)谱研究了ZnO薄膜的结构和光学性能.结果表明,ZnO薄膜具有六方纤锌矿结构,(002)衍射峰较强,c轴择优取向良好.在可见光范围,ZnO薄膜的平均透射率>80%,而在紫外范围,平均透射率急剧降低.拟合得到ZnO薄膜的禁带宽度为3.31eV.随激发波长增加,PL谱峰位没有变化,但强度发生了变化.同时,随测量温度升高,紫外发光峰强度减弱,峰位红移,半高宽展宽.理论拟合得到ZnO薄膜的活化能为59meV,接近于ZnO体材料的激子束缚能(60meV),说明紫外发光是由自由激子辐射复合引起的. 相似文献
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采用脉冲激光,在Si(001)衬底上生长ZnO薄膜,利用X射线衍射(XRD),原子力显微镜(AFM)和光致发光光谱(PL)等测试手段研究了不同衬底温度所生长的ZnO薄膜结构特征和光学性能。研究表明:衬底温度影响ZnO薄膜结构和光学性能。在500℃~600℃沉积范围内随着温度升高,ZnO薄膜结构和光学性能提高。 相似文献
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铝掺杂氧化锌薄膜的光学性能研究 总被引:1,自引:0,他引:1
采用溶胶-凝胶法,在玻璃基底上制备了掺杂不同质量分数Al的ZnO薄膜,并采用X射线衍射(XRD)仪、扫描电子显微镜(SEM)、紫外-可见光谱仪(UV-Vis)、光致发光光谱(PL)等方法测试和分析了不同Al掺杂浓度对ZnO薄膜的形貌结构、光学性能影响。结果表明,Al的掺杂引起了晶体生长过程中择优取向的改变,掺杂ZnO薄膜的表面颗粒随Al掺杂量的增加而增大,可见光范围内的平均透射率78%,光致发光光谱分析表明,纯的ZnO薄膜有很强的紫外发光,而随Al的质量分数的增加,紫外发光强度迅速下降。 相似文献
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Cr掺杂ZnO薄膜晶体结构及光学性能的研究 总被引:1,自引:0,他引:1
采用磁控溅射法在载玻片上制备了不同Cr掺杂浓度的ZnO薄膜,并对其紫外发光性能做了初步研究.XRD结果表明,所制备的样品具有纤锌矿结构,呈c轴择优取向生长;透射谱表明,改变Cr掺杂浓度可以使ZnO薄膜的吸收边向短波方向移动,并且薄膜的禁带宽度连续可调;光致发光(PL)谱表明,所有样品的PL谱由发光中心位于370nm的紫外发光峰组成,且该峰的峰位蓝移,与吸收边缘移动的结果吻合.2.0%(原子分数,下同)的Cr掺杂可以提高ZnO的紫外发光强度,而过量的Cr掺杂反而会降低其紫外发光强度. 相似文献
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Zinc oxide is getting an enormous attention due to its potential applications in a variety of fields such as optoelectronics, spintronics and sensors. The renewed interest in this wide band gap oxide semiconductor relies on its direct high energy gap (Eg ∼ 3.437 eV at low temperatures) and large exciton binding energy. However to reach the stage of device production the difficulty to produce in a reproducible way p-type doping must be overcome.In this study we discuss the structural and optical properties of ZnO films doped with nitrogen, a potential p-type dopant. The films were deposited by magnetron sputtering using different conditions and substrates. The composition and structural properties of the films were studied combining X-ray diffraction (XRD), Rutherford backscattering (RBS), and heavy ion elastic recoil detection analysis (HI-ERDA). The results show an improvement of the quality of the films deposited on sapphire with increasing radio-frequency (RF) power with a preferentially growth along the c-axis. The ERDA analysis reveals the presence of H in the films and a homogeneous composition over the entire thickness. The photoluminescence of annealed samples evidences an improvement on the optical quality as identified by the well structured near band edge recombination. 相似文献
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以无水乙醇、乙二醇甲醚、乙二醇甲醚/乙醇混合溶液(1∶1)为溶剂体系,采用溶胶-凝胶法制备了ZnO透明薄膜,并利用场发射扫描电镜、X射线衍射和反射光谱仪等研究了溶剂体系对薄膜组成、结构和光学性能的影响。结果表明,3种溶剂所制备的ZnO薄膜均为六方纤锌矿型结构,具有c轴择优取向;以乙二醇单甲醚/乙醇混合溶液(1∶1)为溶剂制备的ZnO薄膜平整、致密,在可见光区域透光率达到90%左右,禁带宽度为3.25eV,具备制作薄膜太阳能电池透明导电电极材料的应用价值。 相似文献
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Zinc oxide (ZnO) thin films were deposited on Si substrates using various working pressures by magnetron sputter. The resistivity of the deposited ZnO films decreases with working pressure, and the resistivity of 4.3 × 10−3 Ω cm can be obtained without post annealing. According to the optical transmittance measurements, the optical transmittance above 90% in the wavelength longer than 430 nm and about 80% in the wavelength of 380 nm can be found. Using time-resolved photoluminescence measurement, the carrier lifetime increases with working pressure due to the reduction of nonradiative recombination rate. The reduction of nonradiative recombination rate is originated from the decrease of oxygen vacancies in the ZnO films deposited at a higher working pressure. This result is verified by the photoluminescence measurements. Besides, by increasing the working pressure, the absorption coefficient was decreased and the associated optical energy gap of ZnO thin films was increased. 相似文献
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Diluted magnetic semiconductor epitaxial thin films of Zn1 − xMnxO have been grown on c-sapphire by the MOCVD technique. Variations of a and c lattice parameters follow Vegard's law and attest to the incorporation of substitutional Mn2+ ions. Carrier concentration (n-type) and electron mobility were studied versus temperature for different concentrations of manganese. Incorporation of manganese leads to the opening of the band gap, observed as a blue shift in energy regarding pure ZnO. 相似文献
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使用Zn(CH3COO)2·2H2O和PVA水溶液混合的办法在Si衬底上生长了微孔结构的ZnO薄膜。样品的晶体结构、形貌及光致发光性使用XRD、SEM及PL谱进行表征。结果表明所制备的ZnO为六方纤锌矿型晶体结构,微孔的孔壁是由纳米颗粒聚集而成,颗粒尺寸大约为20nm,关于这种结构的形成,我们推测PVA在微孔结构的形成过程中起到了模板作用。 相似文献
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Porous, transparent and controllable ZnO nanoparticulate films were fabricated by self-hydrolysis of zinc salts in its crystalline water without any additions at 65 °C by an evaporating acetone solvent. The crystallite size of ZnO nanoparticles was about 30 nm, and the thickness of the nanoparticle film was controllable by simply changing the coating times. ZnO nanoparticulate films in thickness of 500 nm showed a high transmittance (>90%) in the visible range and widen bandgap (3.35 eV). The c-axis oriented ZnO nanoarray film was fabricated by a subsequent heterogeneous nucleation and growth in an aqueous solution. As-grown ZnO hybrid films showed a good transmittance (>85%) in the visible range. 相似文献
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Uniform and transparent thin films of Zn1 − xCoxO (0 ≤ x ≤ 0.10) were fabricated by sol-gel spin coating technique. Co addition up to x = 0.075, led to refinement in structure and improvement in film quality together with average grain size reduction from 17 nm in undoped ZnO to 15 nm with x = 0.05 and 12 nm with x = 0.10 Co additions. For x ≥ 0.035, CoO (cubic) was detected as the secondary phase. Influence of Co addition on the volume fraction of grain boundaries has been interpreted. Increase in Co content in the range 0 ≤ x ≤ 0.10 led to quenching of near-band edge and blue emissions, decrease in band gap energy (Eg) from 3.36 eV to 3.26 eV, decrease in film thickness and refractive index and an increase in extinction coefficient of Zn1 − xCoxO thin films. The change in nature of stress from compressive to tensile with lower to higher doping of Co is corroborative with the angular peak shift of (002) plane of ZnO lattice. An overall increase in microhardness of Zn1 − xCoxO thin films up to x = 0.05 is attributed to change in microstructure and evolution of secondary phase and as the secondary phase separates out the overall stress is released leading to lowering of hardness after this concentration. Hall-Petch behavior is also studied and found to obey until x = 0.05, however, considerable deviation after this dopant concentration is attributed to the increase in the volume fraction of grain boundaries, which results from the secondary phase separation from this dopant concentration. 相似文献
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Ge doped ZnO films were deposited on Si substrates by sputtering technique. With the increasing annealing temperature, the crystal quality of samples becomes gradually better and the phase transition can be observed at annealing temperature of 600°C. X-ray photoelectron spectroscopy results show the incorporation of Ge into the ZnO films with 14·81 at-%Ge content. Fourier transform infrared spectroscopy absorption spectra of samples annealed at above 600°C display vibration mode of ν (ZnO4) and ν (GeO4) in Zn2GeO4. The enhancement of ultraviolet emission intensity should be attributed to the yielded mass holes caused by Ge doping and the rising crystal quality. The sample annealed at 800°C displays the strongest blue emission due to the native defects in Zn2GeO4 films or/and surface defects. 相似文献