A combinatorial approach of developing alloy thin films using co-sputtering technique for displays

In this study we have used a combinatorial approach for producing binary and ternary alloy thin film libraries using a lab-scale RF co-sputtering system. Initially we used two elemental sputtering targets, i.e. aluminum (Al) target and neodymium (Nd) target, to produce a film library of varying composition and successfully identified a suitable composition range (1.95―2.38 at% Nd) in which resistance to hillock formation and resistivity of the film spots were found to be satisfactory in annealed state (350℃, 30 min). In another case, in order to form ternary alloy composition library we have used two sputtering targets, i.e. an Al-0.5 at% Nd alloy target and an elemental Ni target. Though, co-sputtered Al-0.6 at% Nd-0.9 at% Ni alloy films showed satisfactory resistance to hillock formation and low resistivity after annealing, film deposited from a ternary alloy target with the same composition failed to show satis- factory resistance to hillock formation during annealing. In case of Al-0.6 at% Nd-0.9 at% Ni alloy target, 250 nm thick film showed poor resistance to hillock formation than the 500 nm thick film. This clearly showed thickness-dependent hillock performance of Al-0.6 at% Nd-0.9 at% Ni alloy. In this study it was found that, in addition to the process variables, metallurgical microstructure of the alloy sputtering targets had significant effect on the film properties which was not obvious from the results of films deposited using co-sputtering of the individual elemental targets.     

Composition design and properties of CoNbZr amorphous films deposited by unbalanced magnetron sputtering

Co₈₇Nb₁₀Zr₃, Co₇₆Nb₁₉Zr₅, Co₆₄Nb₂₆Zr₁₀ and Co₆₄Nb₁₆Zr₂₀ amorphous films were deposited on noncrystalline glass substrates by DC unbalanced magnetron sputtering. The compositions of amorphous films were tailored in the light of the individual deposition rate of Co, Nb and Zr. The amorphous films with the anticipated composition were prepared by means of co-sputtering Co, Nb and Zr targets simultaneously. It is indicated that there is interaction among three targets during co-sputtering. The morphology and composition of the films were observed by SEM, AFM and EDS. The structure and magnetic property were measured by XRD and physical property measurement system (PPMS). The coercivity changes with the composition, varying from 240 to 1 600 A/m. After vacuum isothermal annealing at temperatures of 475, 500, 525 and 550 °C for 15 and 30 min, respectively, it is found that high Nb content is beneficial to improving thermal stability of amorphous films. The crystallized films have the mean grain size of 2–19 nm.     

STUDY ON MAXIMUM HYDROGEN CAPACITY FOR Zr-Ni AMORPHOUS ALLOY

To design the amorphous hydrogen storage alloy efficiently, the maximum hydrogen capacities for Zr-Ni amorphous alloy were calculated. Based on the Rhomb Unit Structure Model (RUSM) for amorphous alloy and the experimental result that hydrogen atoms exist in 3Zr1Ni and 4Zr tetrahedron interstices in Zr-Ni amorphous alloy, the numbers of 3Zr-1Ni and 4Zr tetrahedron interstices in a RUSM were calculated which correspond to the hydrogen capacity. The two extremum Zr distribution states were calculated, such as highly heterogeneous Zr distribution and homogeneous Zr distribution. The calculated curves of hydrogen capacity with different Zr contents at two states indicate that the hydrogen capacity increases with increasing Zr content and reaches its raximum when Zr is 75%. The theoretical maximum hydrogen capacity for Zr-Ni amorphous alloy is 2.0 (H/M). Meanwhile, the hydrogen capacity of heterogeneous Zr distribution alloy is higher than that of homogenous one at the same Zr content. The exrperimental resu     

Ta/Al合金薄膜TCR的方差分析

在用直流共溅射法制备Ta/Al合金电阻薄膜的工艺中,研究了主要工艺参数,例如靶基距、气压、溅射电压和热处理时间等对薄膜电阻温度系数(TCR)的影响。采用方差分析和正交试验方法获取薄膜的最佳工艺条件和TCR值。结果表明只要适当选取和很好控制四种主要工艺参数就可以制出TCR性能优良的Ta/Al合金薄膜,同时证实了方差分析法行之有效。     

Photocatalytic Activities of Amorphous TiO2-Cr Thin Films Prepared by Magnetron Sputtering

Chrome-doped titanium oxide films were prepared by reactive magnetron sputtering method. The films deposited on glass slides at room temperature were investigated by atom force microscope, X-ray diffractometer, X-ray photoelectron spectroscopy, UV-Vis spectrophotometer,the photoluminescence (PL) and ellipse polarization apparatus. The results indicate that TiO2-Cr film exists in the form of amorphous. The prepared films possess a band gap of less than 3.20 eV, and a new absorption peak. The films, irradiated for 5 h under UV light, exhibit excellent photocatalytic activities with the optimum decomposition rate at 98.5% for methylene blue. Consequently, the thickness threshold on these films is 114 nm, at which the rate of photodegradation is 95% in 5 h. When the thickness is over 114 nm, the rate of photodegradation becomes stable. This result is completely different from that of crystalloid TiO2 thin film.     

射频溅射功率和掺杂氢对硅氢薄膜结构的影响

采用SEM和Raman谱对射频磁控溅射法制备的硅氢薄膜结构进行了研究,讨论了在100～400W范围内溅射功率和氢气分压对硅氢薄膜结构的影响。结果表明,制备的硅氢薄膜为致密的颗粒膜,添加氢气后,颗粒状的硅氢薄膜出现了粒径更为细小的纳米级小颗粒亚结构;随着氢气分压的增加,其直径先增加后减小,平均直径在氢气分压为50％时达到最大;随着溅射功率的增加,硅氢薄膜的颗粒平均直径增加,当溅射功率达到400W时,颗粒的平均直径为104nm。拉曼光谱分析结果显示硅氢薄膜为非晶态。     

Photocatalytic activities of amorphous TiO<Subscript>2</Subscript>-Cr thin films prepared by magnetron sputtering

Chrome-doped titanium oxide films were prepared by reactive magnetron sputtering method. The films deposited on glass slides at room temperature were investigated by atom force microscope, X-ray diffractometer, X-ray photoelectron spectroscopy, UV-Vis spectrophotometer, the photoluminescence （PL） and ellipse polarization apparatus. The results indicate that TiO2-Cr film exists in the form of amorphous. The prepared films possess a band gap of less than 3.20 eV, and a new absorption peak. The films, irradiated for 5 h under UV light, exhibit excellent photocatalytic activities with the optimum decomposition rate at 98.5% for methylene blue. Consequently, the thickness threshold on these films is 114 nm, at which the rate of photodegradation is 95% in 5 h. When the thickness is over 114 nm, the rate of photodegradation becomes stable. This result is completely different from that of crystalloid TiO2 thin film.     

Nano-sized Thin Films Fabricated by Ion Beam Sputtering and Its Properties

Nanoscale thick amorphous Ni-Cr alloy thin films were fabricated by low-energy ion beam sputtering technology; then the as-deposited samples experienced rapid thermal process to realize the transformation from amorphous to crystalline state. The film thickness was measured with a-stylus surface profiler, the structure and the compositions of the films were confirmed by low angle X-ray diffraction and scanning auger electron microprobe respectively, and the surface topography was characterized by scanning electron microscope and scanning probe microscope. Electrical property of the films was measured by fourpoint probe. The experimental results illustrate that the combined processes of ion beam sputtering and rajid thermal process are effective for fabrication nanoscale Ni-Cr alloy thin film with good properties.     

封闭式电子回旋共振等离子体低温沉积SrTiO3膜

在室温条件下，用封闭式电子回旋共振(MCECR)等离子体溅射方法沉积了SrTiO3(STO)膜．用Ar等离子体在Si基片上溅射的STO膜是非晶的，然而用Ar／O2等离子体在Pt／Ti／SiO2／Si上溅射的是充分结晶的STO膜．为了使非晶薄膜结晶，用电炉加热或28GHz微波辐射对非晶STO膜进行退火处理．采用微波辐射，使基片温度为573K时，在Si上的STO膜退火后的介电常数大约为260，这值近似等于块状STO材料的介电常数．由于微波辐射能够降低薄膜的退火温度和提高薄膜的电特性，因而被认为是非常有用的．     

金属Y和Cr共掺杂W2N薄膜的力学及摩擦学性能研究

采用磁控溅射法,通过改变氩氮比率,在Si(100)衬底上成功制备了W₂N薄膜,当氩氮比率为20:6时薄膜的结晶性最好.为了改善W₂N薄膜的力学和摩擦学性能,采用射频和直流磁控共溅射方法分别在Si(100)和A304不锈钢衬底上制备了软质金属Y和硬质金属Cr共掺杂的W₂N(Y-Cr:W₂N)薄膜.在掺杂功率20～50 W范围内,当掺杂功率为30 W时,薄膜具有最大硬度,为23.71 GPa,此时样品的弹性模量为256.34 GPa; 当掺杂功率为20 W时,薄膜的平均磨擦系数最小,为0.37.这表明,金属Y和Cr的掺入使W₂N薄膜的力学和摩擦学性能有了很大的改善.     

工艺参数对Ta/Al合金电阻薄膜性能的影响

Al原子含量约为50%的Ta/Al合金薄膜具有优良的电阻性能。使用直流共溅射的方法制作这种薄膜,靶极采用了Al面积为45%的Ta/Al复合靶。研究了工艺参数如溅射气压、溅射电压以及热处理条件等因素对该薄膜的性能影响。结果表明,这种Ta/Al合金薄膜能用于制作功率稳定的电阻器或电阻网络。     

Microstructure and Oxidation Resistance of V Thin Films Deposited by Magnetron Sputtering at Room Temperature

Vanadium films were deposited on Si(100) substrates at room temperature by direct current (DC) magnetron sputtering.The microstructure and surface morphology were studied using scanning electron microscopy (SEM) and atomic force microscope (AFM).The oxidation resistance of films in air was studied using X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM).The results showed that the amorphous vanadium film with a flatter surface had higher oxidation resistance than the crystalline film when exposed to atmosphere.The rapid formation of the thin oxide layer of amorphous vanadium film could protect the film from sustained oxidation,and the relative reasons were discussed.     

类金刚石薄膜的离子注氮研究

以25～35kV的高能离子束将离子化的双原子分子N+2注入非晶态碳膜,硬度可提高10GPa量级.分析研究表明:离子注氮并没有改变碳膜的非晶态结构,但所有拉曼结构参数发生变化,且碳、氮结合能峰位发生化学位移;显然注入的氮和碳形成化学键,并可能形成新相. 结论:类金刚石薄膜离子注氮可合成氮化的类金刚石,改变化学结构,提高机械性能.     

偏压对磁控溅射Cr-N薄膜组织及性能影响

采用磁控溅射离子镀制备Cr-N薄膜,研究基体偏压对Cr-N薄膜组织结构和性能的影响。分别用辉光放电光电子谱(GDOES)、场发射扫描电镜(FESEM)和X射线衍射(XRD)分析薄膜成分和组织结构,显微硬度计测量薄膜硬度。结果表明,薄膜为非化学计量比的Cr-N薄膜,N/Cr原子比均小于0.25,薄膜主要以Cr的衍射峰为主。在偏压达到60 V后薄膜显示了较高的硬度(25 GPa),其归因于离子轰击导致的薄膜的致密度的提高。偏压超过60 V后,致密度达到饱和,硬度增加不明显。     

Li0.33La0.56TiO3薄膜电解质的结构和光电性能

采用射频磁控溅射法,自制Li0.33La0.56TiO3陶瓷靶材,在不同基片温度下沉积了Li0.33La0.56TiO3薄膜。利用X射线衍射仪、原子力学显微镜、电化学工作站、紫外-可见分光光度计等现代测试手段,研究了基片温度对薄膜的结构、形貌、光学和电学性能的影响。结果表明:所制备的Li0.33La0.56TiO3薄膜为非晶态结构,在可见光波段具有较高的透过率;随着基片温度从50℃升高到300℃,薄膜表面更为平整致密,离子电导率逐渐增加。     

Crystallization and conductivity mechanism of ITO films on different substrates deposited with different substrate temperatures

ITO thin films were grown on PC(polycarbonate), PMMA(polymethyl methacrylate) and glass substrates by r.f. magnetron sputtering. The electrical, structural and chemical characteristics of ITO films were analyzed by the Hall Technique, X-ray diffraction, and X-ray photoelectron spectroscopy. XPS studies suggest that all the ITO films consist of crystalline and amorphous phases. The degree of crystallinity increases from less than 45% to more than 90% when the substrate temperature increases from 80 to 300 ℃. The In and Sn exist in the chemical state of In3+ and Sn4+, respectively, independent of substrate type and temperature. The enrichment of Sn on surface and In in body of ITO films are also revealed. And, the oxygen deficient regions exist both in surface layer and film body. For ITO films deposited under 180 ℃ , the carrier concentration are mainly provided by oxygen vacancies, and the dominant electron carrier scattering mechanism is grain boundary scattering between the crystal and the amorphous grain. For ITO films deposited over 180 ℃, the carrier concentration are provided by tin doping, and the dominant scattering mechanism transforms from grain boundary scattering between the crystal grains to ionized impurity scattering with increasing deposition temperature.     

改变过渡层碳靶功率在铜上沉积类金刚石膜的研究

类金刚石膜具有硬度高、 摩擦系数低、 耐腐性强、 稳定性高等优点, 是提高铜耐腐性的理想材料, 但铜 与类金刚石膜之间的结合力差。通过制备T i xC y 过渡层, 采用磁控溅射物理气相沉积与化学气相沉积法, 通过改变 过渡层碳靶功率成功在铜基体上沉积类金刚石膜。并对金刚石膜进行拉曼光谱测试、 划痕实验和电化学实验分析。 结果表明, 所制备碳膜具有典型的类金刚石结构, 膜与基体之间的结合强度大, 过渡层碳靶溅射功率为2 0 0W 时所 制备的类金刚石膜对铜基体的保护作用最好。     

Al掺杂对ZnO薄膜结构和光学性能的影响

研究了Al掺杂对采用直流磁控溅射方法制备的ZnO薄膜结构及光学性能的影响。X射线衍射结果揭示薄膜具有良好的C轴择优取向生长特性,同时,衬底温度对它们的透射谱和荧光谱有着明显影响,所有薄膜都有大于86%的可见光透过率和陡峭的本征吸收边,但ZAO薄膜的光学透过率略低。Al掺杂导致了更宽的光学带隙,光致发光光谱显示ZnO具有较强的近带本征吸收峰和深能级发射峰,但Al掺杂使得深能级发射峰降低。随着衬底温度的升高,近带边吸收峰蓝移,与光学带隙Eg变化趋势一致。     

Impacts of hydrogen dilution on growth and optical properties of a-SiC:H films

Hydrogenatedamorphoussiliconcarbon(a-SiC:H)filmshavefoundagreatdealofusesinsolarcells[1],thinfilmtransistors[2],lightemittingdiodes[3],ultravioletimagesensors[4],microfluidiccoatings[5]andprotectivebarrierforcorrosionorthermaloxidation[6,7],becauseofitsuniquepropertiessuchaswideopticalbandgap,highmechanicalhardnessandchemicalstability.However,astheCcontentincreases,theelectronicandstructuralpropertiesofthefilmstendtobeinferior[8].Althoughinrecentyearsmuchworkhasbeendevotedtoexploringthedeposi…     

W掺杂量对非晶态Ti02：W薄膜光学带隙的影响

在不同的W靶溅射功率下，用反应磁控溅射法在载玻片上制备了TiO2：W薄膜，并对样品进行了XRD，STS和UV-Vis分析，结果表明试样为非晶态；w靶溅射功率为30w时，带隙为2．75eV；W靶溅射功率为100W时，带隙为3．02eV；W靶溅射功率为150W时，带隙能为2．92eV．STS分析结果表明，在样品的禁带中产生了新的能级，能级宽度为0．83eV．