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1.
本研究了利用YSZ(Y稳定的ZrO2)缓冲层在Si衬底上单靶偏轴溅射Bi-Sr-Ca-Cu-O高温超导薄膜的工艺条件,给出了YSZ和BSCCO薄膜的性能测试结果,并根据电镜分析结果,提出了BSCCO薄膜的螺旋柱状生长机理。  相似文献   

2.
PdCl2/SiO2 Pd—B/SiO2非晶态合金催化剂的Ramman光谱表征   总被引:1,自引:0,他引:1  
采用共焦显微Raman光谱和X-射线衍射方法表征了负载型PdCl2/SiO2和Pd-N/SiO2非晶态合金催化剂的结构。结果表明PdCl2分散在SiO2载体上后,与载体表面的相互作用使其在室温时即发生β→α构型转变。Pd-B/SiO2非晶态合金的raman光谱在300-500cm^-1区域内呈现一大的弥散峰。与无负荷Pd-B非晶态合金比较初步认定该弥散峰与Pd-B键振动有关,温度升高Pd-B/Si  相似文献   

3.
此文用从头计算法,在HF、MP2、MP3水平下,使用基组6—31G、6—31+G对SiO的等电子分子SiXm(X=Be、B、C、N、P、Ne,m=-4~+2)进行了几何优化,并计算了相应的平衡几何构型下的振动频率,对SiO分子,使用QCISD(T)方法考虑了不同水平下的电子相关效应,并考虑了不同基函数6-31+G和6-311+G的影响。计算结果表明,所有分子的势能曲线都有稳定的极小值,并且键长与频率在HF、MP2、MP3水平上都呈现出明显的规律性,通过与实验上存在的稳定分子SiO相比较,可以预言NSIi-和SiF+比其它分子有较明显的成键可能性,所以,NSi-和SiF+有可能形成稳定的分子。  相似文献   

4.
用标准固相反应法,我们制备了Bi1.6Pb0.4Sr2Ca2Cu3Oy和Bi2CaCu2Oy纯相样品,在液氮温度下测量了Cu-NQR和B-NQR静态谱,发现NQR谱都为大宽包,Cu-NQR谱线位置反映铜原子所处的氧环境,Bi2Sr2Cu2Oy的NQR谱宽反映其调制结构,Bi1.6Pb0.4Sr2Ca2Cu3OyNQR谱宽取决于其掺杂浓度。由于电场梯度弥散很大,Bi-NQR谱很难观察。  相似文献   

5.
KrFLaser-inducedDamagetoZrO_2/SiO_2Coatings¥WANGNaiyan;GAOHuailin(ChinaInstituteofAtomicEnergy,P.O.Box275-7,Bejijng102413,Chin...  相似文献   

6.
设计并用磁控溅射方法制备了非晶Si/SiO2超晶格结构,以高纯多晶Si为靶材,当以Ar+O2为溅射气氛时,得到SiO2膜,仅以Ar为气氛时,得到Si膜。重复地开和关O2气,便交替地得到SiO2和Si膜。衬底在靶前往返平移,改变平移的速度或者改变溅射的功率,可以控制膜的厚度。通过透民镜的照片可以看出SiO2和Si膜具有均匀的周期结构,用低角X-射线反射谱表征了超晶格的周期结构和各层的厚度。透射光谱表  相似文献   

7.
PdCl_2/SiO_2和Pd-B/SiO_2非晶态合金催化剂的Raman光谱表征   总被引:1,自引:0,他引:1  
采用共焦显微Raman光谱和X-射线衍射方法表征了负载型PdCl2/SiO2和Pd-B/SiO2非晶态合金催化剂的结构。结果表明PdCl2分散在SiO2载体上后,与载体表面的相互作用使其在室温时即发生β→α构型转变。Pd-B/SiO2非晶态合金的Raman光谱在300-500cm-1区域内呈现一大的弥散峰。与无负载Pd-B非晶态合金比较初步认定该弥散峰与Pd-B键振动有关,温度升高Pd-B/SiO2催化活性下降,其主要原因为Pd-B/SiO2非晶态合金在高温下逐渐晶化为Pd金属所致。PdCl2与SiO2载体表面的相互作用使其具有较高的分散性,由此还原制备的Pd-B/SiO2非晶态合金较之无负载Pd-B非晶态合金更加微细化,因而具有更大的活性比表面  相似文献   

8.
GIANTMAGNETO-IMPEDANCEINFe-BASEDSOFTFERROMAGNETICRIBBONSChenChenMeiLiangmoDepartmentofPhysics,ShandongUniversity,Jinan250100...  相似文献   

9.
此文用从头计算法,在HF,MP2,MP3水平下,使用基组6-31G,6-31+G对SiO的等电子分析SiX^m(X=Be,B,C,N,F,Ne,m=-4~+2)进行了几何优化,并计算了相应的平衡几何构型下的振动频率,对SiO分子,使用QCISD(T)方法考虑了不同水平下的电相关效应,并考虑了不同其函数6-31+G和6-311+G的影响。计算结果表明,所有分子的势能曲线都有稳定的极小值,并且键长与频  相似文献   

10.
本文应用SCC-DV-Xa方法计算了(RSi)4Se6,(RSi)2Se3和R4Si3Se4(R=CH3,C2H5,Ph)等分子簇的结合能,轨道能级,电荷分布,状态密度,分析了簇的稳定性,NMR化学位移,紫外可见吸收和催化性能等,结果与实验相符。  相似文献   

11.
衬底材料对制备立方氮化硼薄膜的影响   总被引:2,自引:0,他引:2       下载免费PDF全文
较系统地研究了不同衬底材料对制备氮化硼薄膜的影响。用热丝增强射频等离子体CVD法,以NH3,B2H6和H2为反应气体,在Si,Ni,Co和不锈钢等衬底材料上,成功生长出高质量的立方氮化硼薄膜,还用13.56MHz的射频溅射系统将c-BN薄膜沉积在Si衬底上,靶材为h-BN(纯度为99.99%),溅射气体为氩气和氮气的混合气体,所得到的氮化硼薄膜中立方相含量高于90%,用X射线衍射谱和傅里叶变换红谱对样品进行了分析表明,衬底材料与c-BN的晶格匹配情况,对于CVD生长立方氮化硼薄膜影响很大,而对溅射生长立方氮化硼薄膜影响不大。  相似文献   

12.
Molybdenum single layers were grown by ion beam sputter deposition onto [001] Si substrates. Argon or xenon was used as sputter gas. The layer growth was monitored by real-time in situ spectroscopic ellipsometry in the visible spectral region. A volume phase transition from amorphous to polycrystalline molybdenum layer growth was observed during the deposition process. The time regime of the phase transition as well as the layer thickness at which the phase transition occurs, depends on the sputter regime, especially on sputter species and deposition-pressure range. The thermodynamic approach of energy minimisation is discussed as the driving force for the Mo phase transition. A moderate backscattered particle bombardment of the growing molybdenum film provides the activation energy for the recrystallisation process. A self-diffusion-like process is made responsible for atomic rearrangement of the entire as-deposited thin-film volume. The molybdenum phase transition is connected to thin-film densification and therefore volume contraction. PACS 68.65.Ac; 81.15.Cd; 78.67.Pt  相似文献   

13.
This work describes about the control on phase formation in titanium oxide thin films deposited by reactive dc magnetron sputtering. Various phases of titanium oxide thin films were deposited by controlling the oxygen partial pressure during the sputtering process. By adding nitrogen gas to sputter gas mixture of oxygen and argon, the oxygen partial pressure was decreased further below the usual critical value, below and above which the sputtering yields metallic and oxide films, respectively. Furthermore, nitrogen addition eliminated the typical hysteretic behaviour between the flow rate and oxygen partial pressure, and significantly influenced the sputter rate. On increasing the oxygen partial pressure, the ratio between anatase and rutile fraction and grain size increases. The fracture cross-sectional scanning electron microscopy together with the complementary information from X-ray diffraction and micro-Raman investigations revealed the evolution and spatial distribution of the anatase and rutile phases. Both the energy delivered to the growing film and oxygen vacancy concentrations are correlated with the formation of various phases upon varying the oxygen partial pressure.  相似文献   

14.
Thin silver films were prepared by direct current magnetron sputtering in a single-ended in-line sputter system at various substrate temperatures and in O2 contents in sputter gas, and their electrical, optical, structural and morphological properties together with the compositional properties were investigated. When deposited at room temperature, the electrical and optical properties of Ag films deteriorated with addition of O2 to sputter gas. Deposition of Ag films in O2 added sputter gas promoted the formation of Ag crystallites with (2 0 0) plane parallel to the substrate surface. The electrical resistivity and optical reflection of Ag films deposited above 100 °C were not affected by the sputtering plasma containing oxygen. X-ray photoelectron spectroscopic analysis showed that Ag films deposited above 100 °C in O2 added sputter gas did not possess surplus oxygen in the film, and that the oxidation states of these films were almost identical to that of Ag films deposited in pure Ar gas.  相似文献   

15.
许旻  贺德衍 《光学学报》2004,24(6):43-746
V2O5薄膜具有很好的离子注入/退出可逆性,是最有潜力的锂离子储存层的候选材料之一,它的电学特性与制备方法、化学计量比、结构和取向等有直接关系,仔细控制工艺参量是制备出在锂电池上应用的V2O5薄膜关键。研究中采用脉冲磁控反应溅射方法,通过精确地控制氧分压、基底温度等关键工艺参量,在石英玻璃和硅片上制备V2O5薄膜。利用X射线衍射和X射线光电子谱,分析了薄膜的成分、相结构、结晶和价态情况,用原子力显微镜表征了薄膜的微观结构,用分光光度计测量从200—2500nm波段V2O5薄膜纯度高、相结构单一、结晶度好。高低温电阻变化2个量级,薄膜的光学能隙为2.46eV。  相似文献   

16.
Gang Qi 《Applied Surface Science》2010,256(10):3249-3252
Formation of cubic boron nitride by r.f. magnetron sputtering has been studied with O2 addition to the common working gas Ar/N2. The chemical and the phase composition were determined with Auger electron spectroscopy sputter depth profiling and Fourier transform infrared spectroscopy. The result shows that oxygen hinders the formation of cBN in sufficient nitrogen-supply, but facilitates the growth of cBN in insufficient nitrogen-supply. With insufficient nitrogen-supply, there exists an optimal oxygen-supply in the working gas that promoted the establishment of the stoichiometric condition in the growing film. O-concentration in the film increases with oxygen-supply in the working gas. cBN forms only when the oxygen concentration is below 5% and cN/cB (ratio of concentration of nitrogen atoms and boron atoms) is 1 in the film.  相似文献   

17.
This study employs RF magnetron sputter technique to deposit high C-axis preferred orientation ZnO thin film on silicon substrate, which is then used as the piezoelectric thin film for a thin film bulk acoustic resonator (FBAR). Electrical properties of the FBAR component were investigated by sputtering a ZnO thin film on various bottom electrode materials, as well as varying sputter power, sputter pressure, substrate temperature, argon and oxygen flow rate ratio, so that structural parameters of each layer were changed. The experimental results show that when sputter power is 200 W, sputter pressure is 10 mTorr, substrate temperature is 300 °C, and argon to oxygen ratio is 4:6, the ZnO thin film has high C-axis preferred orientation. The FBAR component made in this experiment show that different bottom electrode materials have great impact on components. In the experiment, the Pt bottom electrode resonant frequency was clearly lower than the Mo bottom electrode resonant frequency, because Pt has higher mass density and lower acoustic wave rate. The component resonant frequency will decrease as ZnO thin film thickness increases; when top electrode thickness is higher, its resonant frequency also drops, due to top electrode mass loading effect and increased acoustic wave path. Therefore, ZnO thin film and top/bottom electrode thickness can be fine-tuned according to the required resonant frequency.  相似文献   

18.
The detection of Na in insulating samples by means of time of flight-secondary ion mass spectrometry (ToF-SIMS) depth profiling has always been a challenge. In particular the use of O2+ as sputter species causes a severe artifact in the Na depth distribution due to Na migration under the influence of an internal electrical filed. In this paper we address the influence of the sample temperature on this artifact. It is shown that the transport of Na is a dynamic process in concordance with the proceeding sputter front. Low temperatures mitigated the migration process by reducing the Na mobility in the target. In the course of this work two sample types have been investigated: (i) A Na doped PMMA layer, deposited on a thin SiO2 film. Here, the incorporation behavior of Na into SiO2 during depth profiling is demonstrated. (ii) Na implanted into a thin SiO2 film. By this sample type the migration behavior could be examined when defects, originating from the implantation process, are present in the SiO2 target. In addition, we propose an approach for the evaluation of an implanted Na profile, which is unaffected by the migration process.  相似文献   

19.
For photocatalytic thin film applications TiO2 is one of the most important materials. The most studied TiO2 crystal phase is anatase, though also rutile and brookite show good photoactivity. Usually anatase or a mixture of rutile and anatase is applied for powder or thin film catalysts. It has been claimed that amorphous films do not exhibit any or only a very low photocatalytic activity.We have deposited amorphous thin films by dc magnetron sputtering from sub-stoichiometric TiO2−x targets. The coatings are transparent and show a photocatalytic activity half of that of a thin layer of spin-coated reference photocatalyst powder. Annealing the thin films to yield anatase crystallization more than doubles their photocatalytic activity. At the same film thickness these thin films show the same activity as a commercially available photocatalytic coating.The dependence of the photocatalytic activity on deposition parameters like gas pressure and sputter power is discussed. A decrease in film density, as deduced from the refractive index and the microstructure, resulted in an increase in photocatalytic activity. Film thickness has a marked influence on the photocatalytic activity, showing a strong increase up to 300-400 nm, followed by a much shallower slope.  相似文献   

20.
用一种新型磁控溅射气体凝聚团簇源产生Cu-n(n是团簇原子个数)团簇束 ,当团簇束分别在偏压为:0,1,3,5,10 kV的电场中加速后,在真空中,沉积在室温下的 P型Si(111)衬底上,获得Cu/P-Si(111)薄膜样品.用X射线光电子能谱(XPS)分析薄膜,结果表明:薄膜本身不含C和O等杂质;当Cu/P-Si(111)样品暴露在空气中时,样品表面会氧化和碳污染,铜的特征电子峰几乎被湮没.用能量3 keV流强为4~6 μA/cm2*!Ar+束, 预溅射处理样品表面后,用XPS分析,常规磁控溅射室温下得到的Cu/P-Si(111)样品和铜团簇束沉积,偏压分别为0,1,3,5,10 kV的样品XPS谱和块状Cu标样谱基本一样,Cu2P1、Cu2P3、 CuLMM特征峰位没有移动,反映不出原子结合能差异.  相似文献   

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