首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 953 毫秒
1.
 研究了不同衬底-阴极距离、直流电压和H2流量对a-CH薄膜沉积速率的影响。结果表明:衬底-阴极距离必须大于0.5cm,随着该距离的增加,薄膜的沉积速率减少;直流电压达550V时沉积速率最大;随着H2含量的增加,CH4含量相对减少,沉积速率随之降低。用AFM观察了以该方法制得的448.4nm CH薄膜的表面形貌,表面粗糙度约为10nm。最后测出了不同条件下CH薄膜的UV-VIS谱,由此可以计算得到薄膜的禁带宽度及折射率。  相似文献   

2.
Tungsten nitride thin films were deposited on stainless steel-304 substrates by using a low energy (2 kJ) Mather type plasma focus device. X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM) and microhardness are used to study the surface of treated samples. The XRD analysis shows that the degree of crystallinity of deposited thin films strongly depends on axial and angular positions of samples. The SEM micrographs of the deposited films at different angular positions (0°, 10° and 30°) and axial position of 8 cm show that the content of WN sub-micro crystalline structures on the surface of deposited films decreased with increasing the angle with respect to anode axis. From AFM results we observe that for the sample deposited at 8 cm and 0° axial and angular positions, respectively, the most uniform surface and the most homogenous distribution of grains are obtained. Also the hardness results show that the highest mechanical hardness is obtained when the film is deposited at 8 cm and 0° axial and angular positions, respectively.  相似文献   

3.
K. Saito  K. Ichioka  S. Sugawara 《哲学杂志》2013,93(30):3629-3641
Thin films of Al–Ni–Co alloy with an average thickness of 15?nm were produced by means of conventional vacuum deposition technique on (0001) sapphire substrates heated at various test temperatures. The microstructures and textures of the films obtained were thoroughly investigated by atomic force microscopy, X-ray diffraction and transmission electron diffraction and imaging techniques. The diffraction measurements have evidenced that the vacuum deposition of Al72Ni15Co13 alloy on the substrates heated above 400°C allows a homogeneous poly-quasicrystalline film, consisting of the Ni-rich basic decagonal phase to grow. It has been further indicated by in-plane XRD analysis that the film deposited at 550°C contains a considerable amount of the decagonal grains epitaxially grown on the sapphire substrate. Possible epitaxial relations occurring between the deposit and the substrate will be detailed on the basis of results obtained from electron diffraction measurements.  相似文献   

4.
Composite films of TiN/Ni3N/a-Si3N4 were synthesized using the Mather-type plasma focus device with varying numbers of focus deposition shots (5, 15, and 25) at 0° and 10° angular positions. The composition and structural analysis of these films were analyzed by using Rutherford backscattering (RBS) and X-ray diffraction (XRD). Scanning electron microscope and atomic force microscope were used to study the surface morphology of films. XRD patterns confirm the formation of composite TiN/Ni3N/a-Si3N4 films. The crystallite size of TiN (200) plane is 11 and 22 nm, respectively, at 0° and 10° angular positions for same 25 focus deposition shots. Impurity levels and thickness were measured using RBS. Scanning electron microscopy results show the formation of net-like structures for multiple focus shots (5, 15, and 25) at angular positions of 0° and 10°. The average surface roughness of the deposited films increases with increasing focus shots. The roughness of the film decreases at higher angle 10° and the films obtained are smoother as compared with the films deposited at 0° angular positions.  相似文献   

5.
Thin Ga2O3 films were grown on Si (100) using trimethylgallium (TMG) and oxygen as the precursors through plasma-enhanced atomic layer deposition. The depositions were made over a temperature range of 80–250?°C with a growth per cycle of around 0.07 nm/cycle. Surface self-saturating growth was obtained with TMG pulse time ≥20?ms?at a temperature of 150?°C. The root mean square surface roughness of the obtained Ga2O3 films increased from 0.1?nm to 0.3?nm with increasing the growth temperature. Moreover, the x-ray photoelectron spectroscopy analysis indicated that the obtained film was Ga-rich with the chemical oxidation states Ga3+ and Ga1+, and no carbon contamination was detected in the films after Ar+ sputtering. The electron density of films measured by x-ray reflectivity varied with the growth temperature, increasing from 4.72 to 5.80?g/cm3. The transmittance of Ga2O3 film deposited on a quartz substrate was obtained through ultraviolet visible (UV–Vis) spectroscopy. An obvious absorption in the deep UV region was demonstrated with a wide band gap of 4.6–4.8?eV. The spectroscopic ellipsometry analysis indicated that the average refractive index of the Ga2O3 film was 1.91?at 632.8?nm and increased with the growth temperature due to the dense structure of the films. Finally, the I-V and C-V characteristics proved that the Ga2O3 films prepared in this work had a low leakage current of 7.2?×?10?11 A/cm2 at 1.0?MV/cm and a high permittivity of 11.9, suitable to be gate dielectric.  相似文献   

6.
Fe/Al thin film multilayers, differing in the thickness of Fe films (30÷10 Å, were electron-beam evaporated in ultra-high vacuum. Interdiffusion and reaction phenomena occurring during deposition at interfaces were studied by means of conversion electron Mössbauer spectroscopy and Auger electron spectroscopy depth-profiling. Magnetic behavior was investigated by alternating force gradient magnetometry. The formation of Fe–Al solid solution and intermetallic compound is observed. Multilayers are ferromagnetic with magnetization in the film plane for iron film thickness ?15 Å, while exhibiting a superparamagnetic behavior at 10 Å.  相似文献   

7.
Combination of pulsed laser ablation with electron cyclotron resonance microwave discharge was demonstrated for a novel method for low-temperature thin film growth. Aluminum nitride thin films were synthesized on silicon substrates at temperatures below 80 °C by means of reactive pulsed laser deposition in nitrogen plasma generated from the electron cyclotron resonance discharge. The synthesized films show a very smooth surface and were found to have a stoichiometric AlN composition. X-ray photoelectron spectroscopy analysis evidenced the formation of aluminum nitride compound. Fourier transform infrared spectroscopy revealed the characteristic phonon modes of AlN. The AlN films were observed to be highly transparent in the visible and near-IR regions and have a sharp absorption edge near 190 nm. The band gap of the synthesized AlN films was determined to be 5.7 eV. The mechanisms responsible for the low-temperature film synthesis are also discussed in the paper. The nitrogen plasma facilitates the nitride formation and enhances the film growth. Received: 17 March 2000 / Accepted: 28 March 2000 / Published online: 23 May 2001  相似文献   

8.
金刚石薄膜的红外椭圆偏振光谱研究   总被引:3,自引:0,他引:3       下载免费PDF全文
采用红外椭圆偏振光谱对微波等离子体化学气相沉积法(MPCVD)和热丝化学气相沉积法(H-FCVD)制备的金刚石薄膜在红外波长范围(2.5—12.5μm)的光学参数进行了测量.建立了不同的光学模型,且在模型中采用Bruggeman有效介质近似方法综合考虑了薄膜表面和界面的椭偏效应.结果表明,MPCVD金刚石膜的椭偏数据在模型引入了厚度为77.5nm的硅表面氧化层、HFCVD金刚石膜引入879nm粗糙层之后能得到很好的拟合.最后对两种模型下金刚石薄膜的折射率和消光系数进行了计算,表明MPCVD金刚石薄膜的红外 关键词: 金刚石薄膜 红外椭圆偏振光谱 光学参数 有效介质近似  相似文献   

9.
空心阴极辉光放电包覆铜纳米粉末   总被引:1,自引:1,他引:0       下载免费PDF全文
 简要叙述了自悬浮定向流方法制备铜纳米粉末的原理和包覆层薄膜的生长机理,采用空心阴极辉光放电对铜纳米粉末进行有机包覆,实验中CH4和H2的流量分别为6 ml/min和12 ml/min,工作电压为450 V,衬底与空心阴极的底端距离为2 cm,背景真空和工作气压分别为6 Pa和100 Pa,沉积速率为7.5 nm/min。用透射电镜(TEM)对铜纳米粉末进行了观察和分析,结果表明:铜纳米粉末呈球状,其粒径分布在10~100 nm之间, 平均粒径大小为50 nm;其包覆层的厚度大约为15 nm,而且该厚度可以通过调节空心阴极辉光放电的参数来控制。  相似文献   

10.
The effect of ion bombardment on the growth of Nb films and their crystal structure is investigated. Epitaxial niobium films with the (001) orientation are grown on (01i2) Al2O3 substrates heated to 600°C and biased at ?20 V. Niobium films with pronounced axial texture in the [110] direction are grown on water-cooled Sitall (devitrified glass such as Pyroceram) substrates. In Nb films biased at ?50 V, which are in the superconducting state, the motion of individual magnetic vortices is observed with a magnetooptic indicator.  相似文献   

11.
Crystalline coiled carbon nano/micro fibers in thin film form have been synthesized via direct current plasma enhanced chemical vapor deposition (PECVD) on copper substrates with acetylene as a carbon precursor at 10 mbar pressure and 750 °C substrate temperature. The as-prepared samples were characterized by X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM) and high resolution transmission electron microscopy (HRTEM). XRD pattern as well as selected area electron diffraction (SAED) pattern showed that the samples were crystalline in nature. SEM and HRTEM studies showed that as synthesized coiled carbon fibers are having average diameter ∼100 nm and are several micrometers in length. The as-prepared samples showed moderately good electron field emission properties with a turn-on field as low as 1.96 V/μm for an inter-electrode distance 220 μm. The variation of field emission properties with inter-electrode distance has been studied in detail. The field emission properties of the coiled carbon fibrous thin films are compared with that of crystalline multiwalled carbon nanotubes and other carbon nanostructures.  相似文献   

12.
Floating potential fluctuations, plasma parameters and deposition rate have been investigated as a function of axial distance during deposition of copper in direct current (DC) magnetron sputtering system. Fluctuations were analyzed using phase space, power spectra and amplitude bifurcation plots. It has been observed that the fluctuations are modified from chaotic to ordered state with increase in the axial distance from cathode. Plasma parameters such as electron density (ne), electron temperature (Te) and deposition rate (Dr) were measured and correlated with plasma fluctuations. It was found that more the deposition rate, greater the grain size, higher the electron density, higher the electron temperature and more chaotic the oscillations near the cathode. This observation could be helpful to the thin film technology industry to optimize the required film.  相似文献   

13.
宋汝安  程先安  周忠毅 《物理学报》1990,39(10):1635-1639
在磁场辅助下电子回旋共振(ECR)效应在大的空间范围形成高密度的等离子体,为大面积金刚石薄膜的淀积提供有利条件,以CH4-H2为原料气体,在Si基片上,在比其他制备方法更低的压强(3Torr附近)下已制备出直径约为5cm的金刚石薄膜,从空间等离子体范围来看且有可能达更大的面积,在分析等离子体发射光谱的基础上,对0.5到50Torr压强的金刚石气相生长条件作了讨论。 关键词:  相似文献   

14.
韩军  张鹏  巩海波  杨晓朋  邱智文  自敏  曹丙强 《物理学报》2013,62(21):216102-216102
本文研究了脉冲激光沉积(PLD)生长过程中, 铝掺量、氧压及衬底温度等实验参数对ZnO:Al(AZO)薄膜生长的影响, 并利用扫描电子显微镜、原子力显微镜、X射线衍射、霍尔效应、光透射光谱等实验手段对其透明导电性能进行了探讨. 变温霍尔效应和光透射测量表明, 当靶材中铝掺量大于0.5 wt%时, 所制备AZO薄膜中铝施主在80 K时已完全电离, 因Bernstein-Moss (BM) 效应其带隙变大, 均为重掺杂简并半导体. 进一步系统研究了氧压和衬底温度对AZO薄膜透明导电性能的影响, 实验发现当氧压为1 Pa, 衬底温度为200 ℃时, AZO 导电性能最好, 其霍尔迁移率为28.8 cm2/V·s, 薄膜电阻率最小可达2.7×10-4 Ω·cm, 且在可见光范围内光透过率超过了85%. 氧压和温度的增加, 都会导致薄膜电阻率变大. 关键词: 脉冲激光沉积法 ZnO:Al薄膜 透光性 导电性  相似文献   

15.
两步化学沉积法制备ZnO薄膜及其场发射特性   总被引:2,自引:1,他引:1       下载免费PDF全文
在低温常压条件下,以ITO玻璃为衬底,采用电化学法与湿化学法结合的两步化学沉积法制备了团簇状ZnO薄膜。利用XRD,SEM分析了薄膜结构和表面形貌,并采用二极管结构在高真空条件下对薄膜进行了场发射性能测试。稳定发射后,开启电场为3.0 V/μm。当电场为5.8 V/μm时,电流密度为583.3 μA/cm2。研究表明:两步化学沉积法低温制备ZnO薄膜是可行的,且该薄膜具有良好的场发射性能。  相似文献   

16.
氮化铝单晶薄膜的ECR PEMOCVD低温生长研究   总被引:10,自引:0,他引:10       下载免费PDF全文
秦福文  顾彪  徐茵  杨大智 《物理学报》2003,52(5):1240-1244
采用电子回旋共振等离子体增强金属有机物化学气相沉积(ECR-PEMOCVD)技术,在c轴取向的蓝宝石即α Al2O3(0001)衬底上,以氮化镓(GaN)缓冲层和外延层作为初始层,分别以高纯氮气(N2)和三甲基铝(TMAl)为氮源和铝源低温生长氮化铝(AlN)薄膜.并利用反射高能电子衍射(RHEED)、原子力显微镜(AFM)和x射线衍射(XRD)等测量结果,研究了氢等离子体清洗、氮化和GaN初始层对六方AlN外延层质量的影响,从而获得解理性与α Al2O3衬底一致的六方相AlN单晶薄膜,其XRD半高宽为1 关键词: AlN 氢等离子体清洗 氮化 GaN  相似文献   

17.
XeCl(308nm)脉冲准分子激光淀积类金刚石薄膜   总被引:9,自引:1,他引:8  
利用XeCl(308nm)脉冲准分子激光淀积技术在功率密度5×108W/cm2、室温、真空度10-3Pa的条件下,制备出不含氢成分的类金刚石薄膜,研究了类金刚石薄膜的特性及其随制备工艺条件的变化规律。研究了激光诱导的碳等离子体发射光谱,探讨了类金刚石薄膜的形成机理。  相似文献   

18.
In order to gain an insight into the processes in an RF styrene plasma, gas phase plasmas were investigated by emission spectroscopy. The plasma reactor was a bell-jar-type chamber with two parallel plate electrodes. The measurement of plasma emission spectra was made with axial resolution. The correlations among the emission intensities of CH and C4H2+ species, the polymer deposition rate and the polymeric structure of the deposited films were studied. The proposed analysis showed that the gas flow pattern in the plasma reactor, and the difference in collisions between styrene monomer molecules and energetic free electrons occurring in the plasma region and RF sheath, made the fragments and ions produced change in the different regions, resulting in a change in polymeric structure and deposition rate of the polymer films. With increasing distance between the substrate position and the lower electrode, the deposition rate and the concentration of phenyl groups both at the polymer surface and in the bulk decreased  相似文献   

19.
The paper presents the influence of pulsed laser deposition (PLD) parameters on the structural and optical properties of PZT thin films grown on platinum substrate. X-ray diffraction (XRD), spectroscopic ellipsometry (SE) and X-ray photoelectron spectroscopy (XPS) are used to determine the thin film properties. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) are employed to get additional information. By changing the distance between target and substrate, different crystalline orientations of PZT are obtained. The thin film thickness and its roughness, as well as the refractive index are also influenced by the chosen distance.  相似文献   

20.
Cu2S thin films deposited on glass substrate by chemical bath deposition were studied at different deposition temperatures and times. The results of X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive X-ray analysis (EDX), the Hall Effect measurement system and UV-Vis absorption spectroscopy indicate that both deposition temperature and time are important to obtain polycrystalline thin films. XRD showed that the polycrystalline Cu2S thin films have monoclinic structure. Meanwhile, the structural variations were analyzed using SEM. EDX analysis results of the thin film showed that the atomic ratio of Cu/S was close to 2:1. It was found from the Hall Effect measurement that the resistivity varied from 4.59?×?10?3 to 13.8?×?10?3 (Ω?cm). The mobility values of the Cu2S thin films having p-type conductivity varied from 15.16 to 134.6?cm2/V.s. The dark electrical resistivity measurements were studied at temperatures in the range 303–423?K. The electrical activation energies of Cu2S thin films were calculated by using Arrhenius plots, from which two different activation energy values are estimated for each thin film. Using UV-Vis absorption spectroscopy (Ultraviolet/visible), the direct and indirect allowed optical band gap values were determined to lie between 2.16 and 2.37?eV and 1.79 and 1.99?eV, respectively. In addition, the values of the refractive index (n) and the extinction coefficient (k) were determined.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号