Characterization of silicon oxynitride thin films deposited by electron beam physical vapor deposition technique

Thin films of silicon oxynitride (SiO_xN_y) were deposited successfully on silicon wafer substrates using electron beam physical vapor deposition (EB-PVD) technique by varying the substrate temperature (T=100–450 °C) and deposition time (t=0.5–2.5 min). The films were characterized by UV–Visible and X-ray photoelectron spectroscopy (XPS), Tally step measurement and Ellipsometry. The minimum reflectivity R=1.72% is obtained for the films deposited under the conditions of T=350 °C, t=1.5 min at λ=548 nm. Further, the characterization results revealed that the refractive index (RI) of the films increases with increase in the substrate temperature due to increase in silicon nitride content. The refractive index and the thickness of the films were found to be in the range of n=1.72–1.90 and d=40–138 nm, respectively. The values n=1.88 and d=79 nm observed corresponding to the minimum reflectivity R=1.72% satisfy the condition of near quarter wavelength single layer antireflection coating. Thus, the above films might have the tremendous potential for antireflective coating applications.     

Optical properties of erbium oxide thin films deposited by electron beam evaporation

Erbium oxide thin films were deposited by electron beam evaporation on substrates heated to 300 °C. The effect of the introduction of oxygen on the structural, chemical and optical properties of the films was investigated. The films were characterized using X-ray diffraction, X-ray photoelectron spectroscopy and normal-incidence transmittance and reflectance. The films had microcrystallites embedded in an amorphous matrix, and their stoichiometry was dependent on the oxygen partial pressure. The transmittance spectra of the films revealed that they were optically inhomogeneous. A model based on an inhomogeneous layer was applied to extract the refractive index and extinction coefficient from the transmittance and reflectance spectra.     

有机玻璃基材表面电子束蒸镀铬-铝-二氧化硅薄膜及其性能研究

采用电子束蒸镀的方法,以有机玻璃为基材,在其表面蒸镀铬过渡层,再蒸镀铝,最后蒸镀保护层二氧化硅.实验结果表明:增加铬过渡层的样品,铝膜结合的非常牢固,附着力得到很大的提高.和未蒸镀二氧化硅保护层的样品进行耐腐蚀性测试对比,发现二氧化硅薄膜具有很好的保护性,铝膜在10%的碱性溶液中完好无损;而没镀二氧化硅保护层的样品,铝膜很快溶解.试验结果表明,采用电子束蒸发技术,在使用合适的工艺参数下,可以在有机玻璃表面制备附着力好、耐腐蚀的高反射铝膜.     

Dielectric properties of ytterbium oxide films deposited by electron beam evaporation

Experimental data for the dielectric properties of thin ytterbium oxide (Yb₂O₃) films deposited in MIM structures are presented. Yb₂O₃ films were obtained by reactive vacuum evaporation using an electron beam. The capacitance of the MIM structures was determined for various dielectric thicknesses (d = 30?200 nm) over the temperature range 130–600 K at a frequency of 1 kHz. The dielectric permittivity and temperature coefficient of capacitance were determined. The influence of various electrodes on the structure capacitance was examined. The breakdown field strength was determined. The results are compared with those previously obtained for Yb₂O₃.     

Properties of polycrystalline silicon grown on insulating substrates by electron beam gun evaporation

Growth of polycrystalline silicon on insulating substrates such as glass, silicon dioxide and fused quartz was studied using an electron beam gun evaporation technique. Growth characteristics were studied as a function of substrate temperature. The results of scanning electron microscopy, secondary ion mass spectrometry and X-ray diffraction studies on various films are presented. Hall mobility, resistivity and carrier concentration measurements are also presented. Growth of polycrystalline films (as determined by X-ray diffraction studies) on glass substrates at as low a temperature as 525 °C were observed. Below this substrate temperature, films became amorphous. The grain size increased with the increase in the substrate temperature. The highest value of the Hall mobility measured was about 10 cm² V⁻¹ s⁻¹. Both n-type and p-type films were obtained.     

Optical and electrical properties of TiOx thin films deposited by electron beam evaporation

The TiO_x thin films were prepared by electron beam evaporation using TiO as the starting material. The effect of the annealing temperature on the optical and electrical properties was investigated. The spectra of X-ray photoelectron spectroscopy reveal that Ti in the films mainly exist in the forms of Ti²⁺ and Ti³⁺ below 400 °C 24 h annealing. The charge transfer between different titanium ion contribute greatly to the color, absorption, and electrical resistance of the films.     

Fullerene films deposited by evaporation in vacuum using spot-focused annular electron beam

A rapidly focused annular electron beam can provide for the effective evaporation of a fullerene mixture in a vacuum of ～10^?2 Pa. A 1-kW beam focused into a spot within 0.1–1 s produces explosive evaporation of a fullerene target at an extremely high efficiency of heating. A comparison of the Raman and electronic absorption spectra of the initial fullerene powder and a film deposited upon its evaporation shows that C₆₀ and C₇₀ fullerenes are evaporated without rupture of C-C covalent bonds. The electron beam evaporation in vacuum has been successfully used to obtain fullerene films on substrates with an area of ～0.1 m².     

Optical properties of NiO thin films fabricated by electron beam evaporation

Nickel oxide (NiO) thin films were deposited onto quartz substrates by the electron beam deposition technique, and obtained high crystal quality after annealing at 1173 K. The structural and microstructural properties of the films were studied by X-ray diffraction (XRD) and atomic force microscope (AFM), respectively. We focus on the optical characterization of the films, indicating the enhancement of the crystal quality, which was confirmed by the photoluminescence and Raman spectrum. Furthermore, PL studies exhibited room temperature emission at 377 nm, and also shown high ultraviolet/visible rejection ratio (>100).     

An orientation competition in yttria-stabilized zirconia thin films fabricated by ion beam assisted sputtering deposition

A previously found orientation competition in ion beam sputtered yttria-stabilized zirconia thin films was studied in detail. The effects of sputtering energy and deposition angle were analyzed in ion sputtered films without assisting ions bombardment. It is found that for normally deposited films, (001) and (011) orientations are favored at low and high sputtering energy respectively. For inclined substrate deposited films, as deposition angle increases, (001), (011) and (111) orientations are advantaged in turn. The results can be attributed to the in-plane energy exchange of deposition atom and adatoms. In ion beam assisting deposited YSZ films of low assisting ions energy and current, a (001) oriented biaxial texture is gradually induced as ion energy increased. In the case of ion beam assisted inclined deposition of 45°, (001) orientation is enhanced and two preferential in-plane orientations are found coexist.     

Characterization of the silicon oxide thin films deposited on polyethylene terephthalate substrates by radio frequency reactive magnetron sputtering

Transparent silicon oxide films were deposited on polyethylene terephthalate substrates by means of reactive magnetron sputtering with a mixture of argon and oxygen gases. The influences of process parameters, including the oxygen flow ratio, work pressure, radio frequency (RF) power density and deposition time, on the film properties, such as: deposition rate, morphology, surface roughness, water vapor/oxygen transmission rate and flexibility, were investigated. The experimental results show that the SiO_x films deposited at RF power density of 4.9 W/cm², work pressure of 0.27 Pa and oxygen flow ratio of 40% have better performance in preventing the permeation of water vapor and oxygen. Cracks are produced in the SiO_x films after the flexion of more than 100 cycles. The minimum transmission rates of water vapor and oxygen were found to be 2.6 g/m² day atm and 15.4 cc/m² day atm, respectively.     

Characterization of transparent conducting oxide thin films deposited on ceramic substrates

In this work, we investigate the optical and electrical properties of various transparent conductive oxide (TCO) thin films deposited on insulating ceramics for emerging optoelectronic applications. Thin films investigated include indium tin oxide (ITO), ruthenium oxide (RuO₂), and iridium oxide (IrO₂) on Al₂O₃ ceramic substrates. The conducting films have been deposited by various techniques including RF magnetron sputtering and low-cost spray pyrolysis. The morphological characteristics of the films were carried out using high magnification optical microscopy and atomic force microscopy (AFM). Optical and electrical characterization was carried out by optical absorbance/transmittance, van der Pauw, current-voltage (I-V), and Hall effect measurements. The results are presented in this paper.     

低能电子束制备硅基纳米薄膜微结构研究

本文提出了一种新颖的结合自组装技术和电子束直写曝光以及选择性化学沉积制备图案化薄膜方法。利用X-射线光电子能谱（XPS），扫描电子显微镜（SEM），透射电子显微镜（TEM）紫外可见光谱仪（Analytic Jena AG）进行了表征。结果表明该方法取得了选择性较好的图案化金薄膜微结构图形。文中对胶体金纳米颗粒尺寸的选择以及金薄膜图案的粘附性能也进行了探讨。该方法有望应用于微／纳电子工业中。     

Low-temperature epitaxy of silicon by electron beam evaporation

In this paper we report on homoepitaxial growth of thin Si films at substrate temperatures T_s = 500-650 °C under non-ultra-high vacuum conditions by using electron beam evaporation. Si films were grown at high deposition rates on monocrystalline Si wafers with (100), (110) and (111) orientations. The ultra-violet visible reflectance spectra of the films show a dependence on T_s and on the substrate orientation. To determine the structural quality of the films in more detail Secco etch experiments were carried out. No etch pits were found on the films grown on (100) oriented wafers. However, on films grown on (110) and (111) oriented wafers different types of etch pits could be detected. Films were also grown on polycrystalline silicon (poly-Si) seed layers prepared by an Aluminum-Induced Crystallisation (AIC) process on glass substrates. Electron Backscattering Diffraction (EBSD) shows that the film growth proceeds epitaxially on the grains of the seed layer. But a considerably higher density of extended defects is revealed by Secco etch experiments.     

电子束蒸发制备纳米硅锥及其场发射性能研究

应用超高真空电子束蒸发方法，以铁作为催化剂，在硅和多孔硅衬底上生长纳米Si锥阵列。采用原子力显微镜表征生长在不同衬底上纳米硅的形貌特征，测试和比较了不同衬底上纳米硅的电子场发射性能。实验结果表明用这种方法形成了高度为10—35nm的锥状纳米结构，并且这些纳米硅锥阵列的场发射性能良好。比较生长不同衬底上的纳米锥形貌与场发射性能，发现多孔硅衬底上更适合生长这种纳米硅锥。     

Chemical vapor deposition of electrolyte thin films based on yttria-stabilized zirconia

Gas-tight electrolyte films are obtained by chemical vapor deposition for solid oxide fuel cells from yttria-stabilized zirconia (YSZ) with a thickness of 4–15 μm on supporting porous ceramic anodes (YSZ/NiO). Volatile metal complexes with dipivaloylmethane Zr(dpm)₄ and Y(dpm)₃ are used as precursors. On the basis of an analysis of thermal properties of the starting compounds, parameter ranges in deposition processes are determined. Dependences of the structure, composition, and electrical characteristics on deposition conditions are found for YSZ electrolyte films. Electrochemical solid oxide fuel cells that operate at low temperatures with an open circuit voltage of 0.98–1.08 V and specific power up to 440 mW/cm² at 1073 K and 1200 mW/cm² at 1173 K are constructed.     

Thermoelectric properties of Sb2Te3 thin films by electron beam evaporation

This study applies the thermoelectric grains of Sb2Te3 on conductive glass to evaporate Sb2Te3 thin films by the electron beam evaporation method. Through experimental tests with different evaporation process parameters and film annealing conditions, thin films with better Seebeck coefficient, resistivity (p) and power fact (PF) can be obtained. Experimental results show that when thin films are annealed, their defects can be decreased accordingly, and carrier mobility can be enhanced to further elevate the conductivity of thin films. When the substrate temperature is set at 200 degrees C to fabricate Sb2Te3 thin films by the evaporation process and by annealing at 220 degrees C for 60 minutes, the Seebeck coefficient of Sb2Te3 thin films increase from 87.6 microV/K to 177.7 microV/K; resistivity falls from 6.21 m ohms-cm to 2.53 m ohms-cm and PF can achieve the maximum value of 1.24 10(-3) W/K2 m. Finally, this study attempts to add indium (In) to Sb2Te3 thin films. Indium has been successfully fabricated In3SbTe, thin films. This study also analyzes the effects of In on the thermoelectric properties of In3SbTe2 thin films.     

Agglomeration phenomena of high temperature coefficient of resistance platinum films deposited by electron beam evaporation

Abstracts are not published in this journal This revised version was published online in November 2006 with corrections to the Cover Date.     

不同氧分压下电子束蒸发氧化锆薄膜的特性

在不同的氧分压下用电子束热蒸发的方法制备了氧化锆薄膜。用扫描探针显微镜、X射线衍射仪和分光光度计分别对薄膜的表面粗糙度、微结构和透射谱等特性进行了表征。实验发现,薄膜沉积中氧分压与薄膜性质及微结构有密切的关系。当氧分压由3.0×10-3Pa升高到11×10-3Pa,薄膜的表面粗糙度由3.012nm降低到1.562nm,而薄膜的折射率由2.06降低到2.01。此外,X射线的衍射还发现,薄膜是以四方相为主多相共存的,随着氧分压的增加,特征衍射峰强度逐渐减弱,最后完全变成非晶。