多弧离子镀TiN和(TiZrCr)N膜中宏观颗粒的SEM分析

宏观颗粒是阻碍电弧离子镀广泛应用的障碍。它们镶嵌在膜层中,或散布在膜层表面。引起薄膜微区成分和结构的突变,对于工具镀来讲不一定有害,而对于高档模具和装饰来讲无疑是有害的。由于真空电弧阴极斑点局部温度高达8000～40000K,阴极表面的微小熔池产生喷射,最终形成这些宏观颗粒。许多方法用来减少和消除真空电弧离子镀中的大颗粒。本文比较了在直流偏压、直流迭加脉冲偏压和磁场过滤电弧作用下的宏观颗粒特点。实验方法用4弧源真空电弧离子镀设备进行TiN膜的沉积,用Zr、Cr、Ti靶进行(ZrCrTi)N复合膜的共沉积。工艺条件为:电弧电流80…     

沉积温度对Ti—B—N复合薄膜微结构及力学性能的影响

采用多靶轮流溅射技术，用Ｔｉ和六方氮化硼（ｈ－ＢＮ）反应合成了Ｔｉ－Ｂ－Ｎ薄膜，采用ＸＲＤ、ＴＥＭ和显微硬度计研究了薄膜的微结构及其力学性能。结果表明，室温下沉积的Ｔｉ－Ｂ－Ｎ薄膜为非晶体的Ｔｉ（Ｎ，Ｂ）化合物，其硬度达到ＨＫ２４７０；高温下沉积的薄膜为ＴｉＮ结构类型的Ｔｉ（Ｎ，Ｂ）晶体，薄膜在晶化后硬度略有降低。     

脉冲激光沉积TiN/AlN多层膜的微结构与力学性能

采用脉冲激光沉积(LPA)法,在单晶Si表面制备了调制周期为50nm的不同调制比的TiN/AlN多层膜,并研究了调制比对多层膜微结构和力学性能的影响。扫描电镜(SEM)和原子力显微镜(AFM)显示,薄膜的调制比在1～4之间。并且小调制比下薄膜表面的岛密度小,岛面积过大,分布不均匀,相邻岛之间的起伏较大。X射线衍射(XRD)结果表明,小调制比下,AlN相为明显的(002)择优取向,TiN相主要以(200)、(220)形式存在;调制比增大后,AlN相的择优取向减弱,同时伴随着薄膜晶粒的细化及硬度增强,这一研究结果说明,调制比对多层膜的性质有一定的影响,大调制比会导致Al元素在界面处聚集,并与TiN进行合金化后的形成TiAlN结构,进而对薄膜的硬度产生影响。     

Si间隔层对Al(1wt.%Si)/Zr极紫外多层膜热稳定的作用研究

为了提升Al/Zr多层膜的热稳定性,采用直流磁控溅射方法制备了18个带有不同厚度Si间隔层的Al(1 wt.%Si)/Zr多层膜,并将这些样品分别进行了不同温度(100~500 ℃)的真空退火,退火时间为1 h.利用X射线掠入射反射(GIXR)和X射线衍射(XRD)的方法来研究Si间隔层对Al/Zr多层膜热稳定性的作用.GIXR测量结果表明:随着Si间隔层厚度的增大,Al膜层的粗糙度减小,而Zr膜层的粗糙度增大;XRD测量结果表明:Al和Zr膜层粗糙度的变化是由于退火后膜层中晶粒尺寸不同造成的.相比于没有Si间隔层的Al/Zr多层膜,引入厚度为0.6 nm的Si间隔层可以有效提升Al/Zr多层膜的热稳定性.     

多步退火对(Pb,La)(Zr,Ti)O_3反铁电厚膜的影响

采用溶胶-凝胶技术,在Pt(111)/Ti/SiO2/Si(100)基底上制备Pb0.97La0.02(Zr0.95Ti0.05)O3反铁电厚膜材料,研究了单步和多步退火工艺对反铁电厚膜结构及电学性能的影响。结果表明:与传统的单步退火方式相比,多步退火工艺制备的反铁电厚膜材料晶粒尺寸较大,结构致密性好,室温下反铁电态更稳定,具有良好的择优取向度(100)、较高的介电常数(达529)和饱和极化强度(达42μC/cm2)。其反铁电-铁电和铁电-反铁电的相变电场强度分别为198和89 kV/cm,反铁电-铁电相变电流密度达2×10-5 A/cm2,多次退火工艺可提高反铁电厚膜的成膜质量。     

TC4表面激光熔覆Ti-Al-(C,N)复合涂层的组织与力学性能

为了改善TC4合金的表面性能,在TC4表面预置不同成分的复合粉末,采用激光熔覆工艺制备了Ti-Al-(C, N)复合涂层。通过对涂层的物相组成及微观组织结构进行分析,揭示了复合涂层的合成机理,并结合复合涂层的组织结构特征分析了其硬度分布。结果表明:熔覆层与基体之间形成了良好的冶金结合;熔覆层主要由基体相Ti_xAl_y和树枝晶TiC_1-xN_x组成;激光快速熔凝过程中Al元素扩散进入TiC_1-xN_x相枝晶边缘形成MAX相;合适的粉末配比能使熔覆层的组织细小致密,熔覆层的最高硬度为基体的2.04倍。     

铜(钛)和铜(铬)自形成阻挡层性能表征

采用直流磁控溅射法分别将Cu (Ti)和Cu (Cr)合金层沉积在SiO2/Si衬底上,随后将制得的样品在真空(2×10-3 Pa)中退火1h,退火温度为300 ～ 700℃.对Cu (Ti)及Cu (Cr)自形成阻挡层进行对比研究,通过X射线衍射(XRD)、X射线光电子能谱(XPS)和透射电子显微镜(TEM)观察并表征样品的微观结构.通过半导体分析仪测试样品的电学性能,并分析了其热稳定性.结果表明,在Cu膜中分别加入少量的Ti或Cr可使Cu沿〈111〉晶向择优取向生长.两种样品交界面处的Cu及Si元素含量迅速下降,表明在交界面处自形成阻挡层,抑制了Cu与Si元素之间的扩散.Cu (Ti) /SiO2/Si和Cu (Cr) /SiO2/Si样品漏电流测试结果表明,Cr自形成的阻挡层具有更好的热稳定性.     

Effects of Substrate Materials on Self-Formation of Ti-Rich Interface Layers in Cu(Ti) Alloy Films

In our previous studies, thin Ti-rich layers were found to uniformly cover SiO₂/Si substrate surfaces at the interface with Cu(Ti) alloy films after annealing at elevated temperature. These Ti-rich layers were also found to prevent intermixing between the Cu(Ti) alloy films and the substrate, resulting in a simple barrier formation technique, called “self-formation of the diffusion barrier,” which is attractive for fabrication of ultra-large scale integrated (ULSI) interconnect structures. In the present study, to understand the mechanism of self-formation of the Ti-rich barrier layers on the substrate surface, the effects of SiO₂/Si, SiN/SiO₂/Si and NaCl substrate materials on the interfacial microstructure were investigated. The microstructures were analyzed by transmission electron microscopy (TEM) and secondary ion mass spectrometry (SIMS), and correlated with the electrical properties of the Cu(Ti) interconnects. It was concluded that the chemical reaction of Ti with the substrate materials was essential for the self-formation of the Ti-rich layers.     

Fabrication of Co2Fe(Al,Si) and Co2Fe(Al,Si)/MgO on Ge(111) Substrate and Its Magnetic Properties

We investigated the interfacial effects on magnetic properties in Co₂Fe(Al,Si)/Ge (CFAS/Ge) and CFAS/MgO/Ge systems to demonstrate the effects of the interface structure on magnetic properties. CFAS and CFAS/MgO were deposited on the i-Ge(111) substrate. In-situ reflection high energy electron diffraction (RHEED) patterns showed epitaxially grown CFAS and MgO on Ge(111). According to the X-ray diffraction (XRD) ϕ-scan of CFAS(220), we determined that the crystallographic orientation relationships were CFAS(111)<–110>// Ge(111)<–110> and CFAS(111)<–110>//MgO(111)<–110>Ge(111)<–110>. The magnetic properties were measured by the vibrating sample magnetometer (VSM) and the saturation magnetization M_s value of CFAS with 2-nm thick MgO reached the value of L2₁ ordered one. A uniaxial magnetic anisotropy behavior was observed both in CFAS/Ge and CFAS/MgO/Ge structures after annealing. We confirmed the behavior did not only originate from the CFAS/Ge interface but also CFAS/MgO and the ordering structure.     

退火处理对离子束溅射WO3-x薄膜结构和特性的影响

利用离子束溅射结合后退火处理的方法制备了WO_3-x(0≤x≤1)薄膜,系统研究了不同退火气氛、退火温度和退火时间等条件对WO_3-x薄膜的晶体结构以及电学、光学和电致变色特性的影响。研究发现,当退火温度超过WO3结晶温度后,特别是在湿氧气氛下,退火温度越高、退火时间越长,WO_3-x薄膜的结晶度越好,除WO3主晶相显著增强以外,还会陆续出现O29W10、O49W18和WO₂等缺氧相;在干氧条件下,更高的退火温度和更长的退火时间都有助于降低WO_3-x薄膜的电阻值,也都有助于WO_3-x薄膜可见光透过率的提升;WO_3-x薄膜电致变色器件在632.8 nm波长处的光学调制值达到了70%左右,表现出良好的电致变色特性。     

Fabrication of Microcantilever Sensors Actuated by Piezoelectric Pb(Zr0.52Ti0.48)O3 Thick Films and Determination of Their Electromechanical Characteristics

The integration and the device realization of Pb(Zr, Ti)O₃ (PZT) thick films on Si substrates are known to be extremely difficult because the processing temperature of the PZT thick film is close to the melting point of Si. However, PZT thick‐film devices on Si warrant attention as they are appropriate for biological transducers; they generate large actuating forces and have a relatively high sensitivity for mass detection, especially in liquids. In this study, Pb(Zr_0.52Ti_0.48)O₃ thick‐film cantilever devices are successfully fabricated on a Pt/TiO₂/SiN_x/Si substrate using a screen‐printing method and microelectromechanical systems (MEMS) process. Elastic and electromechanical properties such as the Young's modulus and transverse piezoelectric coefficient are determined from microstructural and electrical analyses for further mechanical study. The calculated Young's modulus of the thick film, 53.9 ± 3.85 GPa, corresponds to the resonant frequency obtained from the measured harmonic oscillation response. The transverse piezoelectric constant, d₃₁, of –20.7 to –18.8 pC N^–1 is comparable to that of a dense thin film. These values promise the possibility of determining the resonance properties of a thick‐film cantilever by designing its structure and then simulating the harmonic oscillation response. Using the PZT thick‐film cantilever, a strong harmonic oscillation with a quality (Q) factor of about 23 is demonstrated in water. The observation of strong harmonic oscillation in liquid implies the feasibility of precise real‐time recognition of biomolecules using PZT thick‐film cantilevers.     

sol-gel法制备的ZnO:(Al,La)透明导电膜光电性能

通过X射线衍射、紫外–可见分光光度计、扫描电镜和四探针仪分析等手段,考察了退火温度对ZnO:(Al,La)薄膜微观结构、光学和电学性能的影响,Al掺杂浓度对电阻率的影响。结果表明:随退火温度的升高,薄膜(002)晶面择优取向生长增强,平均晶粒尺寸增大,电阻率降低,透光率上升。在x(Al)为1%,退火温度550℃时,薄膜最低电阻率为1.78×10–3?·cm,平均透光率超过85%。     

硒化温度对Cu(In, Al)Se2薄膜结构和光学性质的影响

采用了磁控溅射制备Cu-In-Al金属前驱体薄膜,后硒化快速退火得到铜铟铝硒(Cu(In,Al)Se2,CIAS)薄膜.研究了硒化温度对CIAS薄膜晶体结构和光学性质的影响.研究发现CIAS薄膜的晶体结构依赖于硒化温度,其禁带宽度随硒化温度升高发生红移.研究结果表明,CIAS薄膜的最佳硒化温度为540℃,其晶体结构为纯黄铜矿结构,禁带宽度为.34 eV,对应太阳电池理论最大效率的吸收层材料禁带宽度     

Growth of In-Rich In x Al1−x N Films on (0001) Sapphire by RF-MBE and their Properties

In-rich In _x Al_1−x N films (0.47 ≤ x ≤ 1) were grown directly on nitridated (0001) sapphire substrates without employing a buffer layer by radiofrequency molecular-beam epitaxy. Both photoluminescence peak energy and optical absorption-edge energy of the In _x Al_1−x N films decreased monotonically with increasing In composition, which was consistent with the recently reported InN bandgap energies of ∼0.7 eV. The bowing parameter of this alloy was estimated to lie between 2.9 eV and 6.2 eV. Substrate nitridation with lower temperature and longer period conditions not only reduced misoriented In _x Al_1−x N phases remarkably but also produced narrower tilt distribution in the c-axis-oriented In _x Al_1−x N matrix.     

The relative stabilities of tungsten hexacarbonyl,silver neodecanoate some metal acetyl- and hexafluoroacetylacetonates and the thermal properties of the palladium(II) acetonates

The relative stabilities of silver neodecanoate, tungsten hexacarbonyl, and a seriesof metal acetyl- and hexafluoroacetyl- acetonates, were determined using differential ther-mal analysis (DTA) and weight loss analysis. In general, the acetylacetonates decom-pose in the solid state at relatively low temperatures (100-200° C), with several of them exhibiting appreciable vapor pressures at temperatures below which their decomposi-tion rate is significant. Hexaf luoro derivatives of these compounds are, in general, more volatile and decompose at higher temperatures. The thermal decomposition behavior of palladium(II) acetylacetonate and palladium(II) hexafluoroacetylacetonate were each investigated using DTA at atmospheric pressure and under each compound’s equilib-rium or decomposition product(s) vapor pressure in conjunction with weight loss and residue composition analysis. At the heating rates employed, ≤2° C/min, palladium(II) acetylacetonate tends to decompose upon heating in either an inert or oxidizing atmo-sphere before significant quantities volatilize. On the other hand, palladium(II) hex-afluoroacetylacetonate tends to volatilize completely before any signs of decomposition are observed under the same conditions. Heating palladium(II) acetylacetonate in ar-gon, at ≤2° C/min, shows the onset of an endotherm at approximately 196° C, at the conclusion of which a product containing 75% palladium was found, the remainder com-prised of carbon, hydrogen and oxygen. In an oxidizing atmosphere at the above men-tioned heating rate, Palladium(II) acetylacetonate decomposes exothermically at 180° C yielding essentially pure palladium. Continued heating in oxygen, to 800° C results in pure PdO. At 900° C, the PdO decomposes yielding pure palladium. Depending upon the heating rates applied, one or two endotherms may be observed during the heating of palladium(II) hexafluoroacetylacetonate. Heating at 2° C/min in either an argon or ox-ygen atmosphere, results in an endothermic transition due to fusion at 105° C in argon (101° C in oxygen), followed by a second endothermic transition at 231° C in argon (223° C in oxygen), due to the normal boiling point being achieved. If heating rates are slow enough,e.g. 0.1° C/min, complete volatilization may occur before the normal boiling point is reached.