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1.
采用控电位沉积方式在p型Si上制备了Ni-Pd合金薄膜;考察了合金的阴极沉积和阳极溶出行为;研究了极化方式对膜组成、厚度、结构及形貌的影响.结果表明,在沉积初期,膜主要以层状方式生长,当膜增厚或阴极极化增强时,则以岛状形式生长.X射线衍射测试表明,Ni-Pd合金呈面心立方结构,其晶面间距随合金组成不同而变化.  相似文献   

2.
提出钯金属复合膜制备的一种新化学镀饰过程,由衬底活化和金属自催化沉积两个主要步骤构成.一般的化学镀饰过程用Pd(Ⅱ)/Sn(Ⅱ)溶液的氧化还原反应活化目标衬底;新的化学镀饰过程是应用溶胶-凝胶技术活化目标衬底,从而明显地简化了镀饰过程.用新的化学镀饰过程制得的钯金属复合膜避免了Sn杂质;在温度314~450℃和膜两侧的压力差002~010MPa的实验条件下,对氢的选择性(氢氮分离系数)为20~130,氢的渗透速率为005~24cm3/(cm2·s).  相似文献   

3.
提出钯金属复合膜制备的一种新化学镀饰过程,由衬底活化和金属自催化沉积两个主要步骤构成,一般的化学镀饰过程用Pd(Ⅱ)/Sn(Ⅱ)溶液的氧化还原反应活化目标衬底;新的化学镀饰是应用溶胶-凝胶技术活化目标衬底,从而明显地简化了镀饰过程,用新的化学镀饰过程制得的钯金属复合膜避免了Sn杂质;在温度314 ̄450℃和膜两侧的压力差0.02 ̄0.10MPa的实验条件下,对氢的选择性(氢氮分离系数)为20 ̄13  相似文献   

4.
用真空双源蒸镀法在NaCl和Si单晶衬底上沉积了RE-Fe(RE:Dy、Y)成分调制多层膜,借助透射电子显微镜(TEM)热台及真空退火方式研究了多层膜受热过程中的结构变化规律。受热温度≤200℃时,多层膜各单层的非晶结构不发生显著变化,且成分调制结构不被破坏,因此,可以认为非昌单支在多层膜在200℃以下的结构是稳定的。  相似文献   

5.
用低压化学气相沉积法制备TiO2薄膜。研究表明,水的分压、沉积温度、基片材料均对沉积速率有影响。在硅片上镀膜,沉积温度相同而退火温度不同,则薄膜结构亦不同。当退火温度高于85℃时,薄膜为纯金红石薄膜。  相似文献   

6.
研究应用等离子体溅射方法制备钯 银合金复合膜 ,并用电子显微镜和高温气体渗透测定来表征膜的质量 .用sol gel方法在工业微滤氧化铝陶瓷膜上沉积纳米孔γ Al2 O3 膜 ,以改善衬底表面的粗糙度 ,降低气相沉积过程中的阴影效应 .以改进钯 银合金膜的气密性为目标来优化等离子体溅射方法的沉积条件 (衬底温度及沉积压力等 ) .典型的钯 银合金复合膜具有氢渗透速率 :0 .0 36× 10 -5 ~ 1.17× 10 -5cm3 /cm2 ·s·Pa ,氢对氮的分离选择性 :5 1.5~ 10 0 0 ,测试条件 :温度为 35 0~ 45 0℃ ,膜两侧压力降为 10 4~ 10 5 Pa  相似文献   

7.
Zr(Y)O2衬底上大面积YBCO薄膜表面组织状态的研究   总被引:1,自引:0,他引:1  
使用配备有EDS和ECP附件的SEM、AEM、和STM研究在750和800℃的Zr(Y)O2衬底上磁控溅射沉积的大面积YBCO超导薄膜的表面组织。YBCO薄膜为c轴取向单晶,但衬底温度为800℃时,膜表面的突出组织多为CuO颗粒,小坑较多,表面粗糙;衬底温度为750℃时,突出组织多为棒状和多边形123结构,很少小坑,表面较平整。  相似文献   

8.
衬底温度对ZnO薄膜生长过程和微结构的影响   总被引:1,自引:0,他引:1  
从原子尺度上去研究薄膜生长过程中温度对薄膜取向性、缺陷结构以及薄膜完整性的影响和作用规律, 对于解释薄膜生长的物理本质、控制生长条件、提高薄膜制备的质量具有重要意义. 本文应用基于反应力场的分子动力学方法研究了ZnO薄膜(000l)表面作为衬底的薄膜沉积生长过程, 初步讨论了衬底温度(200、500和800 K)变化对沉积较薄ZnO膜质量的影响, 部分结果与实验观察相符. 结果表明, 衬底温度在500 K左右时, 沉积原子结构径向分布函数曲线特征峰尖锐、明显, 有序度较高, 注入和溅射对薄膜完整性影响较小, 沉积形成的薄膜结构稳定而又致密. 在预置衬底表面平坦的情况下薄膜呈现一种链岛状的生长模式, 每原子层均具有两种生长取向, 导致其生长前锋交汇处形成了一种新的有序缺陷.  相似文献   

9.
报道了采用双光束紫外激光辅助有机金属化学气相沉积(MOCVD)技术获得氧化锌(ZnO)薄膜(厚度50-200nm)的电镜研究结果。反射高能电子衍射(RHEED)和扫描电子显微镜(SEM)指出,采用该生长在较低生长温度下,在云母衬底上易生长出沿c轴取向的单晶膜。在云母、单晶硅和玻璃衬底上都可得到表面结构致密而均匀的微晶或晶膜。在适当条件下在玻璃衬底上还可以得到非晶膜。这些膜层均具有较好的可见光诱过率  相似文献   

10.
用射频磁控溅射法在(100)SrTio3单晶衬底上外延生长MgO导引层,光刻刻蚀去一半后沉积生长CeO2外延膜,再直流溅射外延生长YBCO超导膜,得到了45°转向结。用X射线θ-2θ扫描和φ扫描研究了各外延膜的结构和取向。  相似文献   

11.
Two-dimensional palladium (Pd) nanostructures have been fabricated by electrochemical deposition of Pd onto an indium tin oxide glass substrate modified with a thin flat film of polypyrrole or a nanofibril film of polyaniline. The experimental results demonstrated that the morphology of Pd nanoparticles strongly depended on the properties of conducting polymers and the conditions of electrochemical deposition. Two-dimensional nanostructures composed of flower-like (consisting of staggered nanosheets) or pinecone-like Pd nanoparticles were successfully synthesized. They can be used as substrates for surface-enhanced Raman scattering after partly decomposing the polymer components by heating in air, and the enhancement factor of the substrate composed of flower-like Pd nanoparticles was measured to be as high as 105 for 4-mercaptopyridine.  相似文献   

12.
淬火温度对聚偏氟乙烯形态结构的影响   总被引:8,自引:0,他引:8  
用透射电子显微镜(TEM)和傅里叶交换红外光谱(FTIR)等方法研究了结晶温度对聚偏氟乙烯(PVF2)晶相结构的影响.结果表明,从PVF2熔体高速淬火到较低温度等温结晶可直接生成β相结晶,临界淬火温度为30℃.淬火温度在40—70℃时,α和β相共存.当淬火温度较高时(80—150℃),生成α相结晶.在淬火温度高于165℃时,则得到PVF2的γ相结晶.在临界温度以下淬火的PVF2薄膜含有β相微晶,而高于临界淬火温度时则生成α相或γ相的片晶或球晶结构.  相似文献   

13.
Bi-layer nanostructures of WO3 (~100 nm and 150 nm) with a very thin film of palladium (Pd~10 nm) on the top, have been studied for hydrogen gas-sensing application at ~700C and medium hydrogen concentrations (1 – 4%) in air. The structures were obtained by vacuum deposition (first the WO3 and then the Pd film) onto a LiNbO3 Y- cut Z-propagating substrate and were tested by means of Surface Acoustic Wave method in a three channel delay line configuration. Very repeatable results have been observed for these two nanostructures with changes in frequency on the level of 500 to 1800 Hz for hydrogen concentration from 1 to 4 % in air. The absolute response value depends on the WO3 film thickness and hydrogen gas concentration and is greater for the nanostructure with a thicker WO3 film.  相似文献   

14.
The Pd/ceramic composite membrane made is reported in this paper. The thin palladium film was deposited on the surface of a porous ceramic substrate by the conventional and improved electroless plating technique, respectively. The rate of palladium deposition increases and especially the sensitization and activation steps in the conventional electroless plating process has been omitted by an improved technique.  相似文献   

15.
汤儆  M.Petri  L.A.Kibler  D.M.Kolb 《电化学》2003,9(2):126-132
应用电化学扫描隧道显微镜(ECSTM)研究了PdSO4溶液中Au(111)电极表面Pd的电化学沉积过程.实验表明,Pd的沉积初始阶段在Au(111)电极表面依次生成两个满单层Pd膜,这一实验结果不仅与电位扫描一致,而且更进一步地证明了起初的两个Pd单层形成过程乃以层~层外延方式生长.高分辨的原子图像表明吸附的SO2-4离子在外延生长的Pd膜表面形成了有序的(3×7)R19°结构.  相似文献   

16.
In this report, the effects of conductive polymer oxidation states and structures on the design and development of ionic liquid (IL)/conductive polymer (CP) composite films for gas sensing are systematically characterized. Four different polyvinyl ferrocene (PVF) films synthesized by varying the conditioning potential (0.7 vs 0.0 V) and the electrolyte are tested for their gas-sensing properties (e.g., sensitivity, selectivity, response time, linearity, and dynamic range against various gas analytes such as dichloromethane, ethanol, natural gas, methane, formaldehyde (37%), and benzene) utilizing the quartz crystal microbalance (QCM) and ATR-FT-IR. The best available film is further studied as a substrate for the immobilization of various ILs that enhanced both the sensitivity and selectivity. Finally, two arrays, each comprising four sensors with the following scheme are developed and characterized for their ability to classify the four target analytes by using linear discriminant analysis: (1) the highest sensitivity PVF film immobilized with four different ILs and (2) the highest sensitivity IL immobilized in four different PVF films. Array 2 is proven to be much better than array 1 in discriminating the analytes, which is very significant in establishing the fact that a diverse set of PVF redox states allow the rational development of a PVF/IL composite-based sensor array in order to analyze complex mixtures utilizing structural differences and the extent of intermolecular interactions.  相似文献   

17.
研究了Pd在氢终止的p型单晶硅(100)表面的自催化化学沉积(AED). 在室温下将刻蚀过的硅片浸入常规的HF-PdCl2-HCl溶液制备了Pd膜. 将沉积了Pd的基底作为工作电极, 用循环伏安法(CV)、原子力显微镜(AFM)和X射线光电子能谱(XPS)研究了Pd膜的阳极溶出行为和形貌. 结果表明, Pd的生长遵循Volmer-Weber (VW)生长模式, Pd膜给出了很好的支持.  相似文献   

18.
Kinetic aspects of parylene N [unsubstituted poly(para-xylylene)] and Parylene C [monochlorosubstituted poly(para-xylylene)] were studied. The conversion of starting material (dimer of either p-xylylene or chloro-para-xylylene) to polymer is quantitative (ca. 100%). Consequently, the total polymer formed in a closed system is directly proportional to the amount of dimer charged. However, the percentage of the total amount of polymer formed which deposits on substrate surfaces, placed in the deposition chamber, as well as the polymer film growth rate are dependent on operational factors such as the temperature of the substrate, sublimation of dimer temperature, flow pattern of the reactive species, etc. Parylene C, being a heavier and more polar molecule, has the tendency to deposit easily in the deposition chamber compared to the deposition of Parylene N. Parylene C also has a higher ceiling temperature for deposition than Parylene N. This situation has been investigated from the viewpoint of excess thermal energy which hinders polymer formation (deposition) due to the exceedingly high entropy change necessary for polymer deposition to occur. The addition of a cool (i.e., room temperature) inert gas was shown to increase the deposition of Parylene N on substrate surfaces placed in the deposition chamber. The deposition increase and acceleration of deposition (film growth) rate were found to be related to the size and molecular weight of the inert gas pressure maintained in the system. The accelerating effect is explained by the increase in third-body collisions to dissipate the excess thermal energy of the reactive species.  相似文献   

19.
张茂峰  杨朝晖  丛海林  曹维孝 《化学学报》2004,62(21):2187-2190
组装于硅片或玻璃片基片上的重氮树脂(DR)单层膜,吸附SnCl2,Pd催化剂后,通过无电沉积的方法,在这些基片上制备了铜膜.对得到的铜膜进行了SEM,XRD表征.通过选择性无电沉积,成功地制备了铜膜图像.  相似文献   

20.
磁控溅射制备择优取向氮化铝薄膜   总被引:3,自引:0,他引:3  
AlN薄膜;磁控反应溅射;磁控溅射制备择优取向氮化铝薄膜;晶面取向;X射线衍射  相似文献   

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