p型导电掺In的SnO2薄膜的制备及表征

采用溶胶-凝胶提拉法成功地制备了p型导电掺In的SnO2薄膜.x射线衍射测试结果表明，掺In的SnO2薄膜保持SnO2的金红石结构.吸收谱测试结果表明，掺In的SnO2禁带宽度为3.8eV.霍尔测量结果表明，空穴浓度与热处理温度有很大的关系，525℃为最佳热处 理的温度.铟锡原子比在0.05—0.20范围内，空穴的浓度与In的含量有直接的关系，并随In含量的增加而增加. 关键词： SnO2 溶胶-凝胶法 p型导电     

Superconducting MgB2 films obtained by magnetron sputtering

Superconducting MgB₂ films with a superconducting transition temperature of 24 K were obtained by magnetron sputtering. The high homogeneity of the films was demonstrated by the magneto-optical imaging of the magnetic flux penetration.     

Surface characterization of TiO2 thin films obtained by high-energy reactive magnetron sputtering

This paper presents the results of surface characterization of TiO₂ thin films deposited on different substrates by the use of high-energy reactive magnetron sputtering. Structural investigations carried out by X-ray diffraction (XRD) and atomic force microscopy (AFM) have shown a strong influence of both the substrate type, and its placement in the deposition chamber (relative to the sputtering target), on the structural properties of the films. In all cases, there is evidence for pseudoepitaxial growth. XRD examination showed existence of TiO₂-rutile phase with preferred (1 1 0) orientation and AFM measurements revealed nanocrystalline structure directly after deposition. X-ray photoelectron spectroscopy analysis showed that the TiO₂ films have stoichiometric composition.     

Preparation and characterization of nitrogen-incorporated SnO2 films

Nitrogen-incorporated SnO₂ thin films have been grown on Si(100) and quartz substrates by reactive sputtering of a Sn target in gas mixtures of N₂–O₂. The structure of the nitrogen-incorporated SnO₂ thin films was studied by X-ray diffraction, and the changes in the chemical bonds and atomic binding states of the nitrogen-incorporated SnO₂ thin films were analyzed by X-ray photoelectron spectroscopy. It was found that the binding energy of Sn 3d and O 1s shifts 0.65 eV and 0.35 eV, respectively, toward the lower-energy side after nitrogen was incorporated into the SnO₂ thin films as a comparison with that of pure SnO₂ film. The indirect optical band gap gradually decreases from 3.42 eV to 3.23 eV, i.e. from the UV to the edge of the visible-light range, with increasing nitrogen flux content in the N₂–O₂ gas mixtures. PACS 81.15.Cd; 78.20.-e; 68.37.Xy; 81.05.Je     

Optical characterization and microstructure of BaTiO3 thin films obtained by RF-magnetron sputtering

BaTiO₃ thin films were deposited on Pt/Ti/SiO₂/Si by rf planar-magnetron sputtering. The films thickness increases with the decrease of both deposition pressure and sample-discharge centre distance. The films annealed at 900 °C, for 8 h, present direct band gap energy ranged between 3.57 and 3.59 eV. The dependence of the structure and microstructure (texture, degree of crystallinity), as well as of the optical characteristics on the deposition parameters, was analysed. Using spectroscopic ellipsometry (SE) measurements coupled with the Bruggeman Effective Medium Approximation (B-EMA), the layer structure and the surface roughness, were determined. The root mean square roughness values of the surface layer, estimated by atomic force microscopy (AFM) analyses, are ranged between 10 and 20 nm and were in good agreement with SE data.The obtained films have tetragonal unit cell and show densely packed, non-columnar morphology and hexagon-like crystallite shape.     

射频磁控溅射法制备SnO2:Sb薄膜的结构和光致发光性质研究

采用射频磁控溅射法在玻璃衬底上制备出锑掺杂的氧化锡(SnO2:Sb)薄膜.制备薄膜是具有纯氧化锡四方金红石结构的多晶膜薄,晶粒生长的择优取向为[110].室温下光致发光测量结果表明,在392 nm附近存在强的紫外-紫光发射,研究了不同氧分压对薄膜结构及发光性质的影响,并对SnO2:Sb的光致发光机制进行了探索性研究.     

Electrophysical properties of zinc-sulfide films obtained by high-frequency magnetron sputtering

The structure and electrophysical properties of zinc-sulfide films obtained by high-frequency magnetron sputtering are investigated. It is shown that the electrical strength of the films is no less than 10⁶ V·cnr^–1, the width of the forbidden band is 3.2–3.3 eV, and the refractive index is 1.8. The films are tested as electroluminescent layers in thin-film electroluminescent emitters. Luminescence with a brightness of 150 cd/m² is obtained.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 6, pp. 29–32, June, 1990.It remains to thank A. A. Miller for perfecting the electron-microscope investigations.     

p型导电掺In的SnO_2薄膜的制备及表征

采用溶胶 凝胶提拉法成功地制备了p型导电掺In的SnO2 薄膜 .x射线衍射测试结果表明 ,掺In的SnO2 薄膜保持SnO2 的金红石结构 .吸收谱测试结果表明 ,掺In的SnO2 禁带宽度为 3 8eV .霍尔测量结果表明 ,空穴浓度与热处理温度有很大的关系 ,5 2 5℃为最佳热处理的温度 .铟锡原子比在 0 0 5— 0 2 0范围内 ,空穴的浓度与In的含量有直接的关系 ,并随In含量的增加而增加     

Epitaxial growth of Sc-doped ZnO films on Si by sol-gel route

The epitaxial growth of doped ZnO films is of great technological importance. Present paper reports a detailed investigation of Sc-doped ZnO films grown on (1 0 0) silicon p-type substrates. The films were deposited by sol-gel technique using zinc acetate dihydrate as precursor, 2-methoxyethanol as solvent and monoethanolamine (MEA) as a stabilizer. Scandium was introduced as dopant in the solution by taking 0.5 wt%¹ of scandium nitrate hexahydrate. The effect of annealing on structural and photoluminescence properties of nano-textured Sc-doped films was investigated in the temperature range of 300-550 °C. Structural investigations were carried out using X-ray diffraction, scanning electron microscopy and atomic force microscopy. X-ray diffraction study revealed that highly c-axis oriented films with full-width half maximum of 0.21° are obtained at an annealing temperature of 400 °C. The SEM images of ZnO:Sc films have revealed that coalescence of ZnO grains occurs due to annealing. Ostwald ripening was found to be the dominant mass transport mechanism in the coalescence process. A surface roughness of 4.7 nm and packing density of 0.93 were observed for the films annealed at 400 °C. Room temperature photoluminescence (PL) measurements of ZnO:Sc films annealed at 400 °C showed ultraviolet peak at about (382 nm) with FWHM of 141 meV, which are comparable to those found in high-quality ZnO films. The films annealed below or above 400 °C exhibited green emission as well. The presence of green emission has been correlated with the structural changes due to annealing. Reflection high energy electron diffraction pattern confirmed the nearly epitaxial growth of the films.     

The luminescence enhancement of Eu^3＋ ion and SnO2 nanocrystal co-doped sol-gel SiO2 films

SnO₂ nanocrystal and rare-earth Eu～（3+） ion co-doped SiO₂ thin films are prepared by sol-gel and spin coating methods.The formation of tetragonal rutile structure SnO₂ nanocrystals with a uniform distribution is confirmed by X-ray diffraction and transmission electron microscopy.Fourier transform infrared spectroscopy is used to investigate the densities of the hydroxyl groups,and it is found that the emission intensity from the 5 D 0 7 F 2 transitions of the Eu～（3+） ions is enhanced by two orders of magnitude due to energy transfer from the oxygen-vacancy-related defects of the SnO₂ nanocrystals to nearby Eu～（3+） ions.The influences of the amounts of Sn and the post-annealing temperatures are systematically evaluated to further understand the mechanism of energy transfer.The luminescence intensity ratio of Eu～（3+） ions from electric dipole transition and magnetic dipole transition indicate the different probable locations of Eu～（3+） ions in the sol-gel thin film,which are further discussed based on temperature-dependent photoluminescence measurements.     

Effect of balanced and unbalanced magnetron sputtering processes on the properties of SnO2 thin films

A comparative study has been carried on the role of balanced magnetron (BM) and unbalanced magnetron (UBM) sputtering processes on the properties of SnO₂ thin films. The oxygen partial pressure, substrate temperature and deposition pressure were kept 20%, 700 °C and 30 mTorr, respectively and the applied RF power varied in the range of 150–250 W. It is observed that the UBM deposition causes significant effect on the structural, electrical and optical properties of SnO₂ thin films than BM as evidenced by X-ray diffraction, C-V, Spectroscopic Ellipsometer and Photoluminescence measurements. The value of band gap (E_g) of the films deposited at 150 W in UBM is found as E_g = 3.83 eV which is much higher than the value of E_g = 3.69 eV as observed in BM sputtering indicating that UBM sputtering results in good crystalline quality. Further, the C-V measurements of SnO₂ thin films deposited using UBM at high power 250 W show hysteresis with large flat band shift indicating that these thin films can be used for the fabrication of memory device. The observed results have been attributed to different mechanisms which exist simultaneously under unbalanced magnetron sputtering due to ion bombardment of growing SnO₂ thin film by energetic Ar+ ions.     

Preparation and characterization of Mg-doped ZnO thin films by sol-gel method

Undoped and Mg-doped ZnO thin films were deposited on Si(1 0 0) and quartz substrates by the sol-gel method. The thin films were annealed at 873 K for 60 min. Microstructure, surface topography and optical properties of the thin films have been measured by X-ray diffraction (XRD), atomic force microscope (AFM), UV-vis spectrophotometer, and fluorophotometer (FL), respectively. The XRD results show that the polycrystalline with hexagonal wurtzite structure are observed for the ZnO thin film with Mg:Zn = 0.0, 0.02, and 0.04, while a secondary phase of MgO is evolved for the thin film with Mg:Zn = 0.08. The ZnO:Mg-2% thin film exhibits high c-axis preferred orientation. AFM studies reveal that rms roughness of the thin films changes from 7.89 nm to 16.9 nm with increasing Mg concentrations. PL spectra show that the UV-violet emission band around 386-402 nm and the blue emission peak about 460 nm are observed. The optical band gap calculated from absorption spectra and the resistivity of the ZnO thin films increase with increasing Mg concentration. In addition, the effects of Mg concentrations on microstructure, surface topography, PL spectra and electrical properties are discussed.     

Sb_2Te_3热电薄膜的离子束溅射制备与表征

采用离子束溅射技术交替沉积Sb-Te-Sb多层薄膜后进行高真空热处理,直接制备Sb2Te3薄膜.利用X射线衍射(XRD)仪、霍尔系数测试仪、薄膜Seebeck系数测量系统对所制备的薄膜特性进行表征.XRD测量结果显示,薄膜的主要衍射峰与Sb2Te3标准衍射峰相同,在[101]/[012]晶向取向明显,存在较多的Te杂质峰;霍尔系数测试结果表明,薄膜为p型半导体薄膜,薄膜电阻率较低,其电导率接近于金属电导率,载流子浓度量级为1023cm-3,具有良好的电学性能;Seebeck系数测量结果显示,薄膜具有良好的热电性能,在不同条件下制备的薄膜的Seebeck系数在7.8—62μV/K范围;在所制备的薄膜中,退火时间为6h、退火温度为200℃的薄膜其Seebeck系数达到最大,约为62μV/K,且电阻率最小.     

Deposition and characterization of TiZrV-Pd thin films by dc magnetron sputtering

TiZrV film is mainly applied in the ultra-high vacuum pipes of storage rings.Thin film coatings of palladium,which are added onto the TiZrV film to increase the service life of nonevaporable getters and enhance H_2pumping speed,were deposited on the inner face of stainless steel pipes by dc magnetron sputtering using argon gas as the sputtering gas.The TiZrV-Pd film properties were investigated by atomic force microscope(AFM),scanning electron microscope(SEM),X-ray photoelectron spectroscopy(XPS) and X-Ray Diffraction(XRD).The grain size of TiZrV and Pd films were about 0.42-1.3 nm and 8.5-18.25 nm respectively.It was found that the roughness of TiZrV films is small,about 2-4 nm,but for Pd film it is large,about 17-19 nm.The PP At.%of Pd in TiZrV/Pd films varied from 86.84 to 87.56 according to the XPS test results.