Properties of Gallium Phosphide Thick Films Prepared on Zinc Sul-de Substrates by Radio-Frequency Magnetron Sputtering

Radio-frequency (RF) magnetron sputtering was employed to prepare gallium phosphide (GaP) thick films on zinc sulfide (ZnS) substrates by sputtering a single crystalline GaP target in an Ar atmosphere. The infrared (IR) transmission properties, structure, morphology, composition and hardness of the film were studied. Results show that both amorphous and zinc-blende crystalline phases existed in the GaP film in almost stoichiometric amounts. The GaP film exhibited good IR transmission properties, though the relatively rough surface and loose microstructure caused a small loss of IR transmission due to scattering. The GaP film also showed a much higher hardness than the ZnS substrate, thereby providing good protection to ZnS.     

WO3薄膜制备及其电致变色性能研究

采用直流反应磁控溅射方法在室温下制备WO3薄膜。研究溅射功率对WO3薄膜结构及电致变色性能的影响规律,考察退火后WO3薄膜的结构演变及电致变色性能变化。结果表明溅射功率为270W时薄膜表现出较好的电致变色性能,其调制幅度达78.5%,着色时间为9s,褪色时间为3.2s。将该功率下制备的WO3薄膜进行退火处理,其结构由非晶态转变为晶态,但调制幅度、响应时间特性都发生一定程度的退化。非晶态WO3薄膜相比晶态结构具有更快的响应时间和更宽的调制幅度,但晶态薄膜具有更好的循环稳定性。     

溅射气压对直流磁控溅射ZnO:Al薄膜的影响(英文)

采用直流磁控溅射法在玻璃基片上沉积ZnO:Al(AZO)薄膜,溅射气压为0.2～2.2 Pa.通过X射线衍射(XRD)、扫描电子显微镜(SEM)、四探针和紫外–可见分光光度计对AZO薄膜的相结构、微观形貌和电光学性质进行了表征.结果表明:薄膜的沉积速率随着溅射气压的增大而减小,变化曲线符合Keller-Simmons模型;薄膜均为六角纤锌矿结构,但择优取向随着溅射气压发生改变;溅射气压对薄膜的表面形貌有显著影响;当溅射气压为1.4 Pa时,薄膜有最低的电阻率(8.4×104 Ω·cm),高的透过率和最高的品质因子Q.     

Crystallization behaviour of amorphous SiC films prepared by r.f. sputtering

The crystallization behaviour of amorphous SiC (a-SiC) films prepared by r.f. diode sputtering was studied using IR measurements and transmission electron microscopy. The absorption band at around 800 cm^-1 in the IR spectrum became sharper and more intense when a sample was annealed above 1000°C, corresponding to the phase transition in the film from amorphous to polycrystalline β-SiC. From cross-sectional transmission electron microscopy observations, crystallization occured homogeneously in the film. The crystallization behaviour was independent of the film thickness and the substrate temperature during preparation. The measured overall activation energy of crystallization of a-SiC films is about 5.0 eV.     

Effect of power variation on wettability and optical properties of co-sputtered titanium and zirconium oxynitride films

The present paper deals with deposition of titanium and zirconium oxynitride films prepared from co-sputtering titanium and zirconium targets by reactive RF magnetron sputtering. The effect of power variation on various properties of the deposited films is analysed. The film gets transformed from amorphous to well crystalline oxynitride films with gradual increase of target powers as observed from XRD graphs. The films exhibit hydrophilic and hydrophobic behaviours depending upon the presence of various phases. Surface energy decreases as the film properties change from hydrophilic to hydrophobic due to greater contact angle values. The optical properties were measured by UV–Vis–NIR spectrophotometer, transmission spectra and bandgap values show variation with respect to change in elemental composition as determined from EDS analysis.     

A novel technique for processing functionally graded HA coatings

Hydroxyapatite (HA) films were deposited using dual ion beam sputtering. Deposition was carried out with an in situ heat treatment at three temperature settings during deposition. X-ray diffraction of the films at the surface revealed that the deposited film is composed of hydroxyapatite crystalline and amorphous phases. Cross-sectional transmission electron microscopy analysis displayed that the films have a graded crystal structure with the crystalline layer near the substrate and the amorphous layer at the top surface. Compositional analysis was performed using SEM-EDX at the top surface as well as STEM-EDX at the cross-section of the film. The average calcium to phosphorous ratio at the surface is 1.46, obtained by SEM-EDX. The Ca/P ratios in the crystalline and amorphous layers of the film are 1.6 to 1.7, close to the ratio of 1.67 for HA.     

Structure of nanometer-size crystalline Ti film

A special structure of nanostructured titatium (Ti) thin film prepared by ionbeam sputtering deposition technique has been found by means of X-ray diffractometry and transmission electron microscopy. The results show that the Ti film has a new f.c.c. structure with lattice parameter a = 0.402 nm, which does not exist in the bulk Ti target. The crystalline structure of the samples with grain size less than 5 nm is stable at room temperature, and the formation of this abnormal structure in nanometer-size crystalline Ti thin film is discussed.     

Influence of substrates on the structural and morphological properties of RF sputtered ITO thin films for photovoltaic application

Polycrystalline ITO films were deposited by RF sputtering on three different substrates of glass, p-type (100) and multicrystalline textured silicon wafers. Properties of ITO films were analyzed by XRD, SEM, four point probe system and UV/VIS/IR spectrometer. The ITO film on mono and multi-Si crystallizes in a three-dimensional manner, and a granular crystalline structure is formed with a (222) XRD peak, while the ITO film on glass shows strong XRD (400) peak and grows in two dimensions and a domain structure is formed. Resistivity measurements reveal that resistivity of ITO on glass is minimum due to higher concentration of carriers.     

Effect of reactive gas mass flow on the composition and structure of AIN films deposited by reactive sputtering

The mass flow of the reactive gas during sputtering of AIN has been studied in order to control film stoichiometry as well as film structure and morphology. It has been observed that the film composition and sputtering rate depend strongly on the deposition conditions and, in particular, on the mass flow and the sputtering pressure. It has been possible to deposit transparent, almost stoichiometric as well as non-transparent, metal-rich AIN films. The metal-rich films had a sputtering rate which was a factor of six higher than that for the stoichiometric films. The crystalline texture and the morphology have been studied as a function of the total sputtering pressure for both film types. For the transparent films, this novel deposition procedure may be applied in surface acoustic wave devices. The non-transparent AIN films exhibit some similarities to films obtained by ion vapour deposition or ion-beam-enhanced deposition methods, and the films exhibit interesting tribological properties.     

N掺杂Cu2O薄膜的低温沉积及快速热退火研究

采用氧化亚铜(Cu_2O)陶瓷靶,利用射频磁控溅射沉积法在氮气和氩气的混合气氛下制备了N掺杂Cu_2O(Cu_2O∶N)薄膜,并在N_2气氛下对薄膜进行了快速热退火处理,研究了N_2流量和退火温度对Cu_2O∶N薄膜的生长行为、物相结构、表面形貌及光电性能的影响。结果显示,在衬底温度300℃、N_2流量12sccm条件下生长的薄膜为纯相Cu_2O薄膜;在N_2气氛下对预沉积薄膜进行快速热退火处理不影响薄膜的物相结构,薄膜的结晶质量随退火温度(450℃)的升高而显著改善;快速热退火处理能改善薄膜的结晶质量和缺陷,降低光生载流子的散射,增强载流子的传输,预沉积Cu_2O∶N薄膜经400℃退火处理后展示出较好的电性能,薄膜的霍尔迁移率(μ)为27.8cm~2·V~(-1)·s~(-1)、电阻率(ρ)为2.47×10~3Ω·cm。研究表明低温溅射沉积和快速热退火处理能有效改善Cu_2O∶N薄膜的光电性能。     

Structural and electrochemical properties of vanadium oxide thin films grown by d.c. and r.f. reactive sputtering at room temperature

Vanadium oxide thin films were grown at room temperature by direct current and radio-frequency reactive sputtering systems to compare the structural and electrochemical properties. Rutherford backscattering spectrometry and Fourier transform infrared measurements reveal that the composition of the as-deposited films consists of the V₂O₅ phase regardless of the deposition methods. Wide-angle X-ray diffraction measurements show that the crystallinity of the as-deposited V₂O₅ films is different depending on the deposition method. Films deposited by direct current reactive sputtering were amorphous, whereas films deposited by radio-frequency reactive sputtering were crystalline. Scanning electron microscopy measurements show that the V₂O₅ films grown by radio-frequency reactive sputtering had a large grain size but the films grown by direct current reactive sputtering were amorphous. Charge–discharge measurements taken at room temperature with a constant current clearly indicate that the films grown by direct current sputtering demonstrated typical amorphous behavior, whereas the V₂O₅ films grown by radio-frequency sputtering demonstrated the discharge behavior of crystalline V₂O₅. The origin of the structural and electrochemical properties of film grown by radio-frequency reactive sputtering is a self-bias effect. The self-bias effect induces ion bombardment during the growth of vanadium oxide thin film. These results suggest that direct current reactive sputtering is more desirable for growing amorphous V₂O₅ thin film than radio-frequency reactive sputtering.     

The structural state of epitaxial GaP films of different polarities grown on misoriented Si(001) substrates

The structure of GaP films grown by molecular-beam epitaxy on vicinal Si(1113) substrates has been studied by X-ray diffraction. It is established that the crystalline lattice of a pseudomorphic film rotates about the <110> axis toward increasing deviation from the singular orientation, while the subsequent relaxation leads to rotation in the opposite direction. This is valid for the films of both (001) and (001̄) polarities. Differences between the surface morphologies of relaxed and pseudomorphic GaP films are revealed.

     

A comparison of TiN films produced by reactive d.c. sputtering and ion-assisted deposition

The properties of TiN films produced by reactive d.c. sputtering have been compared with those formed by deposition during irradiation by 10 keV nitrogen ions. Films were deposited on aluminium, nickel, molybdenum, silicon and titanium substrates which were chosen because they have a range of mechanical properties. The composition of the films has been studied by Rutherford backscattering, nuclear reaction analysis and transmission electron microscopy and data concerning their hardness and adhesion are also presented. It was found that the films produced by ion-assisted deposition (IAD) were nearly stoichiometric TiN with a predominant (100) orientation while the reactively sputtered films were less crystalline and contained a significant amount of oxygen and carbon throughout the film. There was also considerable improvement in the adhesion of the IAD films but their hardness was only marginally improved.     

Enhancement of the crystalline quality of reactively sputtered yttria-stabilized zirconia by oxidation of the metallic target surface

Yttria-stabilized zirconia (YSZ) thin films were fabricated on glass substrates by direct current magnetron reactive sputtering. We found out that the crystalline quality of the YSZ film was improved by an oxidation process of the metallic target surface prior to the sputtering deposition process. It is speculated that, at the initial stage of the sputtering, the sputtered particles from the oxidized target surface form a layer with higher degree of crystallization on the substrate, compared with those particles from the metallic target surface. This crystallized layer can enhance the crystallization of the film deposited subsequently. Other sputtering conditions such as sputtering pressure, oxygen flow rate, substrate temperature, and Y₂O₃ content in the film were investigated, for optimization of the crystalline quality of the deposited YSZ film.     

直流反应磁控溅射法注积ZrN薄膜

采用直流反应磁控溅射法淀积ZrN薄膜发现在（100）晶向硅片上ZrN薄膜按（111）晶向生长，控制生长工艺可以获得ZrN（111）晶向的外延生长膜．     

Structures and properties of the Al-doped ZnO thin films prepared by radio frequency magnetron sputtering

Al-doped ZnO thin films were deposited by radio frequency magnetron sputtering using a ZnO target with 2 wt.% Al₂O₃. The structures and properties of the films were characterized by the thin film X-ray diffraction, high resolution transmission electron microscopy, Hall system and ultraviolet/visible/near-infrared spectrophotometer. The Al-doped ZnO film with high crystalline quality and good properties was obtained at the sputtering power of 100 W, working pressure of 0.3 Pa and substrate temperature of 250 °C. The results of further structure analysis show that the interplanar spacings d are enlarged in other directions besides the direction perpendicular to the substrate. Apart from the film stress, the doping concentration and the doping site of Al play an important role in the variation of lattice parameters. When the doping concentration of Al is more than 1.5 wt.%, part of Al atoms are incorporated in the interstitial site, which leads to the increase of lattice parameters. This viewpoint is also proved by the first principle calculations.     

电子透射膜的生成及其对微通道板性能的影响

研究采用有机衬底掩膜技术和冷基底直流溅射在多孔微通道板输入面制备非晶态Al2O3电子透射膜的可行性,讨论在微通道板输入面形成连续电子透射膜与气体辉光放电的关系,测量带膜微通道板的电特性。结果表明,微通道板带膜后电子增益下降、体电阻增加、暗电流降低。     

Properties of Resistivity, Reflection and Absorption Related to Structure of ITO Films

Indium tin oxide (ITO) films were fabricated on polyethylene terephthalate (PET) substrate at room tem- perature using dc magnetron sputtering technique with different sputtering powers. The structural, electrical and optical properties were investigated by X-ray diffraction (XRD), Hall effect, reflection and transmission, respectively. XRD patterns show gradual enhancement of crystalline quality with increasing sputtering power. Significant improvement of Hall mobility due to the reduction of defects was observed though the carrier density varied slightly. Simultaneously, the mean transmission in visible light range decreased severely with increasing sputtering power. Slight move toward shorter-wavelength side of absorption peak was due to the variation of plasma wavelength. The reflection increase of near-infrared light originated from the decrease of resistivity. Finally, band gap was obtained using Tauc s relation and it was consistent with Burstein-Moss shift.     

氧化钒薄膜制备与特性研究

用磁控反应溅射法制备出具有红外敏感特性的氧化钒薄膜,进行了薄膜光电特性的测试.通过AFM和XRD对薄膜的结构和特性进行分析研究,并给出了沉积参数对薄膜性能的影响.     

采用MCECR等离子体溅射方法制备硬碳膜

采用封闭式电子回旋共振(MCECR)等离子体溅射的方法在硅(100)基片上沉积了高质量的硬碳纳米微晶薄膜,膜层厚度约40 nm,采用氩等离子体溅射碳靶.薄膜的键结构采用X射线光电子能谱仪(XPS)分析,纳米结构采用高分辨率透射电子显微镜(HRTEM)分析.本文研究了基片偏压对薄膜的纳米结构、摩擦特性(摩擦系数及磨损率)以及薄膜的纳米硬度的影响.摩擦特性采用POD摩擦磨损仪测试,纳米硬度采用纳米压入仪测试.