磁控溅射制备镍薄膜热阻温度传感器工艺研究

利用镍薄膜的温度电阻特性以及磁控溅射镀膜技术设计并制备了薄膜热阻型温度传感器，为了达到较好的工作稳定性，设计了多层的复合膜系。文中分析了沉积薄膜的工作压力、电源功率、靶基距、退火温度、退火时间等制备工艺参数对热阻薄膜特性的影响，以及工艺参数对所沉积的镍薄膜的膜厚均匀度和温度电阻曲线，温度电阻系数等传感特性的影响。通过调整实验的工艺参数，最终得到电阻温度性能较好的镍薄膜温度传感器。测试结果表明薄膜传感器在0-250℃之间温度电阻曲线有较好的线性度和稳定性。     

真空淀积速率对镍铬硅薄膜电阻电性能的影响

镍铬合金是制造薄膜电阻的常用材料。这种电阻材料虽然电阻率高、高温性能稳定,但正温度系数较大(约2×10~(-4)/℃),不能用作温度系数低的精密电阻。如果在镍铬材料中加入4～10％(重量比)的硅,采用真空蒸发可以制成电阻温度系数很小的镍铬硅系薄膜电阻器。在同一蒸发温度下,镍铬硅这三种成分的蒸汽压相差较大易出现分馏现象,影响到膜层的均匀性以及电阻性能,所以真空淀积条件要严加控制。通常在1600℃蒸发时组元的     

VO2薄膜制备及电学性能

用溶胶-凝胶法制备VO2薄膜.通过熔融、涂膜、烘干和热处理等工艺实验,在非晶玻璃上得到电阻变化2～～3个量级的VO2薄膜.对烘干温度、熔融温度、膜厚和热处理温度对薄膜电学性能的影响进行了初步研究.通过XRD和XPS对薄膜的特性和价态进行了分析.     

Ni－Mo系50℃自补偿应变电阻合金性能研究

对Ｎｉ－Ｍｏ系应变电阻合金成份、加工工艺、合金性能进行了研究。特别对典型合金的Φ０．０３ｍｍ细丝应变电阻性能及制片性能进行了详细地研究。本研究最终为５００℃自补偿应变测量，提供了良好的合金。     

红外微测辐射热计用纳米氧化钒薄膜的制备和性能研究

具有优异热敏性能的氧化钒薄膜材料是红外测辐射热计的首选热敏电阻材料，合适的薄膜电阻及高温度电阻系数的氧化钒薄膜的制备是实现高探测率红外测辐射热计的保证．利用新型对靶反应磁控溅射工艺制备了具有纳米颗粒的氧化钒薄膜材料，确定了最佳工艺参数．对其组成、结构和性能进行了分析，原子力显微镜AFM形貌分析表明薄膜具有均匀致密的表面，X射线光电子能谱分析XPS确定了其组成成分主要为V2O5,VO2和少量的V2O3.在常用作微测辐射热计结构层材料的氮化硅基底上，该薄膜材料在室温附近具有合适的薄膜电阻（大约为每方14kΩ）以及高的温度电阻系数（-3．17％／℃），有望适用于非致冷红外测辐射热计探测器．     

磁控共溅射Ni3 Al合金薄膜的微观结构及电阻特性

研究了室温下采用直流磁控共溅射法在抛光玻璃和Si基底上沉积Ni3Al合金薄膜的制备工艺、微观结构和电阻特性.采用SEM、EDX、AFM、TEM等测试分析了不同基底、溅射功率、工作气压等因素对薄膜微观结构、成分比和电阻特性的影响.结果表明:采用大功率混合溅射可以得到多晶态Ni3Al纳米合金薄膜,且呈多层岛状生长.所得薄膜具有良好的导电性,与玻璃相比,在Si基底上的薄膜表面光滑平整,晶粒更小,电阻率略大.然而随着厚度的减小,薄膜的电阻率增加迅速,发生金属向绝缘体过渡的相变,而厚度较大时这种现象不明显,这表明Ni3Al薄膜相变与厚度及晶格中氧含量有关.     

脉冲激光沉积磷掺杂多晶硅薄膜的压阻性能

采用脉冲激光沉积法(PLD)制备磷掺杂多晶硅薄膜,研究磷掺杂分数对多晶硅薄膜压阻性能的影响。结果表明,随着磷掺杂分数增大,多晶硅薄膜的应变系数先增大后减小。在磷掺杂分数为0.3%(质量分数)时,电阻横向应变系数的绝对值达到最大,为24.3,电阻纵向应变系数的绝对值达到最大,为12.6。横向电阻应变的非线性在1%~2.5%之间,电阻的温度系数为0.05%/℃,应变系数的温度系数为-0.06%/℃。     

γ—FeMnAlCr反铁磁合金电阻应变性能的探索

研究了γＦｅＭｎＡｌＣｒ合金的电阻应变性能。实验结果说明，γＦｅＭｎＡｌＣｒ合金丝的室温电阻应变灵敏系数为４．０～４．２，制成的应变片灵敏系数平均为３．７，远高于目前常用的应变电阻合金。合金发生反铁磁→顺磁转变时灵敏系数将急剧下降，说明γＦｅＭｎＡｌＣｒ合金的高灵敏系数来源于合金的反铁磁自旋有序结构。此外，γＦｅＭｎＡｌＣｒ合金具有较小的机械滞后，但蠕变和电阻温度系数较大，因此它适合于室温的动态应变测量。     

VO_2薄膜及电学开关特性

用溶胶-凝胶法在非晶玻璃上制备VO2薄膜,经过熔融、涂膜、烘干和热处理等工艺最后得到电阻相变2～3个量级的VO2薄膜.对烘干温度、熔融温度、膜厚和热处理温度对薄膜电阻开关特性的影响进行了研究.通过AFM,XRD和XPS对薄膜的结构和特性进行分析.     

激光频率对激光溅射法制备多晶硅薄膜压阻特性的研究

采用脉冲激光溅射法制备硼掺杂多晶硅薄膜,研究了不同频率下多晶硅薄膜的晶粒尺寸以及压阻性能。用扫描电子显微镜表征在不同的激光频率沉积的多晶硅薄膜的表面形貌,以及悬臂梁实验测定在不同的激光频率下沉积的多晶硅薄膜的应变系数。结果表明溅射频率对激光溅射法制备的硼掺杂多晶硅薄膜的晶粒尺寸和压阻性能都有着明显的影响,当频率为3 Hz时多晶硅薄膜的晶粒尺寸较大,约为35~65μm,并且多晶硅薄膜有着良好的压阻性能,其应变系数为36.8,电阻的温度系数为-0.036%/℃,应变系数的温度系数为-0.09%/℃。     

The influence of silicon on properties of deposited Ni-Cr films

Multicomponent alloy thin films based on Ni-Cr with a high silicon content were deposited in a high vacuum onto ceramic flat substrates and investigated. After annealing in air the Ni-Cr-Si films show a high stability. It has been found that the temperature coefficient of resistance has values around zero in a range of the film composition from 5 to 20 at.% Ni, from 20 to 40 at.% Cr and from 50 to 65 at.% Si. This range of the film composition is suitable for the production of metal film resistors by means of sputtering.     

Microstructure and electrical characteristics of Ni-Cr thin films

Microstructure of thin films of different compositions of Ni-Cr alloy, over the range from 40 wt.% to 80 wt.% Ni, deposited on silicon nitride coated GaAs substrates, is investigated under Transmission Electron Microscope (TEM) in as-deposited and annealed conditions. The procedure of wet etching vias through GaAs substrates is used for preparing samples for TEM. Microstructures of as-deposited films of different Ni-Cr alloys are related to the nature of the parent alloy in the binary phase diagram. The microstructural transformations in annealed films of single and two-phase alloy materials are interpreted based on the comparison of TEM micrographs in conjunction with the X-ray diffraction and electron diffraction data. The changes in the electrical characteristics such as resistivity and temperature coefficient of resistance (TCR) of the films in relation to the microstructural transformations are discussed. The effect of superimposing a polyimide layer on the TCR of Ni-Cr films is also discussed.     

合金元素(Ti,Cr,Ni)对IBAD制备的碳膜性质的影响

本文采用离子束辅助沉积技术（IBAD）制备一系列碳膜，重点分析添加合金元素（Ti，Cr，Ni）对薄膜性质的影响。实验结果表明：添加Ti，Cr，Ni元素对碳膜厚度，硬度无明显影响，但提高了薄膜的结合强度，其中加入Ni后，薄膜的结合强度最好；添加合金元素可以显著减小碳膜的摩擦系数；添加Ti元素碳膜的组织以非晶态为主，与纯碳膜相当。相对于类金刚石薄膜，本实验制备的碳膜试样更接近于类石墨膜。     

Properties of evaporated Ni-Cr films with an aluminum content of about 50%

Films with an aluminum content of about 50% in Ni-Cr were produced as a continuation of investigations on multicomponent thin alloy films based on Ni-Cr, because an additional zero transition for the temperature coefficient of resistance (TCR) of these thin films was indicated in the earlier investigations. The alloy films were evaporated in high vacuum onto ceramic substrates and measurements of the TCR and the stability were carried out. It was found that the TCR is less than ±50 ppm K^-1 for aluminum concentrations between 45 and 65 at.%. Such films are suitable for the production of metal film resistors.     

Effect of processing conditions on microstructure and electrical characteristics of Ni thin films

Ni thin films with an intermediate layer of Cr were prepared by using dc magnetron sputtering under different conditions. Effects of deposition temperature, post-deposition annealing on the microstructure and the electrical characteristics were investigated. The relationship between film microstructure and its resistivity was analyzed. It was found that the crystal grains aggregated into large ones when the deposition temperature reached or exceeded 150 °C. This could be explained that high deposition temperature conduced high activation energy, which increased surface mobility of the adatoms. Annealing treatments resulted in the densification of the films. Resistivity of the films strongly depended on grain size and crystallinity. The influence of Cr intermediate layer on the resistivity was also discussed. Compared to annealing treatment, the deposition temperature exhibited larger controlling effect on film resistivity.     

Pulsed laser deposition of NiTi shape memory alloy thin films with optimum parameters

A series of experiments was carried out to optimize the pulsed laser deposition parameters for the fabrication of high quality NiTi shape memory alloy thin films. Smooth NiTi shape memory alloy thin films were deposited at high growth rate with optimum deposition parameters based on the analysis of the relationships among the morphology of the target surface and the deposited thin film, the laser energy, the target–substrate distance, the thin film composition and its growth rate. Crystal structures and phase transformation temperatures of the annealed Ni_49.7Ti_50.3 thin film were characterized by using X-ray diffraction and differential scanning calorimetry, respectively. The martensitic transformation temperature of the crystallized Ni_49.7Ti_50.3 thin film is found to be lower than room temperature and 27°C lower than that of the NiTi target material. These results are attributed to the refined grain size of the thin film and its composition, which deviates slightly from Ni₅₀Ti₅₀.     

Ternary alloy films of Ni-Cr-Al for thin film resistors

Multicomponent thin alloy films based on Ni-Cr with additions of aluminium have been used in the G.D.R. for the production of discrete thin film resistors for more than 10 years. Additions of aluminium stabilize the layer and reduce the temperature coefficient of resistance (TCR) to values of about zero. Three regions have been found up to now in the system Ni-Cr-Al which result in highly stable resistive films with a very low TCR. The properties of these films are determined by the content and the distribution of the phases which are present in the amorphous film. The following phases have been found in structural investigations of vacuum-annealed films: α phase (chromium), β phase (NiAl), γ phase (Ni₃Cr), γ′ phase (Ni₃Al) and γ-γ′ phase (Ni₃(Cr, Al)). Of the three regions, one with less than 3 at.% Al, one with 28–32 at.% Al and one with 45–60 at.% Al, the first two regions have been used for the production of thin film resistors up to now. Films of the third region, which has only been found during the last few years, can be obtained by sputtering.     

Electrical characterization of graphene synthesized by chemical vapor deposition using Ni substrate

In this work, the electrical characterization of graphene films grown by chemical vapor deposition (CVD) on a Ni thin film is carried out and a simple relation between the gate-dependent electrical transport and the thickness of the films is presented. Arrays of two-terminal devices with an average graphene film thickness of 6.9 nm were obtained using standard fabrication techniques. A simple two-band model is used to describe the graphene films, with a band overlap parameter E(0) = 17 meV determined by the dependence of conductivity on temperature. Statistical electrical measurement data are presented for 126 devices, with an extracted average background conductivity σ = 0.91 mS, average carrier mobility μ = 1300 cm(2) V(-1) s(-1) and residual resistivity ρ = 1.65 kΩ. The ratio of mobility to conductivity is calculated to be inversely proportional to the graphene film thickness and this calculation is statistically verified for the ensemble of 126 devices. This result is a new method of graphene film thickness determination and is useful for films which cannot have their thickness measured by AFM or optical interference, but which are electrically contacted and gated. This general approach provides a framework for comparing graphene devices made using different fabrication methods and graphene growth techniques, even without prior knowledge of their uniformity or thickness.     

不同Cr含量的Ni基合金电化学腐蚀行为

利用电化学测试技术研究不同Cr含量的Ni基合金耐Cl-离子水溶液腐蚀的能力。结果表明：Ni基合金耐Cr离子腐蚀性能随着合金中Cr含量的提高而增强,溶液中Cl-离子浓度对Ni-9Cr、Ni-15Cr和Ni-20Cr合金有较大影响,特别是Ni-9Cr合金在0．6mol／LNaCl溶液中腐蚀最为严重,而对于Ni-25Cr和N...     

Ni-Cr/Ti/瓷界面反应机制

采用磁控溅射技术,在Ni-Cr合金表面溅射一层Ti薄膜作为中间层,研究了Ni-Cr/Ti/瓷界面组织结构,产物种类、分布及反应机制。结果表明:Ni-Cr/Ti/瓷界面反应复杂,界面处形成的新物相有Ti2Ni,AlTi3,TiO2,SnCr0.14OX,NiCr2O4和Cr2O3。高温烤瓷过程中,Ti与Ni以稳定的化合物Ti2Ni形式结合,同时Ti与陶瓷中Al2O3反应生成AlTi3化合物,与SnO2和SiO2发生置换反应生成TiO2,TiO2与陶瓷中氧化物结合,更好的实现了Ni-Cr合金与陶瓷的连接。