钽和银的引入对氮化铪薄膜电学及摩擦磨损性质的影响

发布时间：2018-01-16 11:33

本文关键词：钽和银的引入对氮化铪薄膜电学及摩擦磨损性质的影响　出处：《吉林大学》2017年硕士论文　论文类型：学位论文

【摘要】：过渡族金属氮化物(TMN,TM=Ti,Zr,Hf,V,Nb,Ta,Cr,Mo,W)薄膜由于具有高硬度、导电性、耐磨耐腐蚀、热稳定性、化学稳定性、扩散阻挡以及生物相容性被广泛地应用于航空航天、生物医学、微电子器件、汽车工业等领域。在这些应用中,薄膜的电学及摩擦磨损性质起到至关重要的作用,因此改善这些特性十分必要。现有研究表明,引入第二种金属元素可以改变薄膜的电导及摩擦磨损性质。但仍然存在以下问题:1.引入过渡族金属元素。(1)引入第二种过渡族金属元素结构到底是如何演变的,是形成固溶体结构还是多相混合结构?目前报道的结果还存在分歧。(2)引入第二种过渡族金属元素电导率是增加还是减小?现有报道的结果相互矛盾。(3)引起摩擦磨损性能提高的原因是什么?研究者已经发现引入第二种过渡族金属元素可以提高薄膜摩擦磨损性质,但机制不尽相同。有人认为是H3/E2值起决定作用,有人则归因于氧化物的产生。2.引入金属银。(1)目前对于向过渡族金属氮化物中引入银的研究中,银含量基本都低于30 at.%,但高含量的银对薄膜结构及性质的影响鲜有报道。(2)与引入过渡族金属相比,引入银对薄膜结构演变及对性能改善上有何影响及不同?针对以上问题,我们利用共溅射技术向氮化铪薄膜中分别引入钽和银,制备了不同成分的Hf-Ta-N薄膜和Hf-Ag-N薄膜。通过X射线衍射仪(XRD)、拉曼光谱仪、透射电子显微镜(TEM)表征相结构,用X射线光电子能谱(XPS)、X射线能谱(EDS)分析薄膜样品成分,用霍尔等测试电学性质,用扫描电子显微镜(SEM)、光学显微镜、纳米压痕仪、轮廓仪及摩擦磨损仪等表征摩擦磨损性质。研究发现:1.无论Ta含量(x=Ta/(Hf+Ta+N))如何变化,Hf-Ta-N薄膜均为固溶体结构。在HfN薄膜中引入适量的Ta可以改善HfN薄膜的电导率,这归因于电子浓度的增加。本文研究发现,当x=0.03时,Hf-Ta-N薄膜的电导率(8.3×105 Sm-1)最大,分别是纯HfN(4.9×105 Sm-1)和纯TaN(1.6×105 Sm-1)的1.7倍和5.2倍。另外,引入适当的Ta可以减小薄膜的磨损率和摩擦系数,这归因于H/E和H3/E2的增加引起薄膜的抗塑性变形能力增强,从而使薄膜的抗摩擦磨损能力提高。本文研究发现,在x=0.37时,磨损率(1.2×10-6 mm3/Nm)及摩擦系数(0.50)均达到最小值,分别只有纯HfN(11.6×10-6 mm3/Nm和0.65)和纯TaN(2.5×10-6 mm3/Nm和0.55)的10%和77%,49%和91%。2.随着Ag含量(x=Ag/(Hf+Ag+N))的增加,Hf-Ag-N薄膜经历两个阶段的结构演变:阶段(i)当0≤x0.039,薄膜为岩盐结构的固溶体;阶段(ii)当0.039≤x≤1,富银相析出,薄膜为固溶体和富银相两相共存结构。引入Ag可以同时提高HfN薄膜的电导率和摩擦磨损性质。本文研究发现,随着x从0增加到1,薄膜电导率从3.22×105 Sm-1持续增加到33.1×105 Sm-1,这归因于Ag的引入引起了电子浓度的增加,并且高含量Ag使薄膜具有Ag金属特性。当x=0.171时,有最优的摩擦磨损性质,磨损率(0.54×10-6 mm3/Nm)及摩擦系数(0.38)相较于纯HfN(16.7×10-6 mm3/Nm和0.62)分别减小了96.8%和38.7%,这归因于固溶强化和Ag低剪切强度的共同作用。此外,这些结果表明,合金化是提高过渡族金属氮化物的导电性和摩擦磨损性质的有效方法。相较于Hf-Ta-N薄膜,Hf-Ag-N薄膜的结构出现了由固溶体到相分离的转变;电导率的提高归因于Ag比Ta有更高的电子浓度,更有益于薄膜的电导率提高;而摩擦磨损性质的提高是由于H3/E2增加引起薄膜的抗塑性变形能力增强和Ag低剪切强度的共同作用。
[Abstract]:Transition metal nitride (TMN, TM=Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W) films have high hardness, conductivity, wear and corrosion resistance, thermal stability, chemical stability and biocompatibility, the diffusion barrier has been widely used in aerospace, biomedical, microelectronics, automobile industry and other fields. In these applications, the friction and wear properties of thin film electrical and play a vital role, therefore improve these properties is necessary. The existing research shows that the conductivity and friction into second kinds of metal elements can change the film abrasion properties. But there are still the following problems: 1. the introduction of transition metal elements (1. Second) the introduction of transition metal structure in the end is how evolution, is the formation of a solid solution structure or multiphase mixed structure? The reported results also exist differences. (2) the introduction of the second kinds of transition metal conductivity is increased also Is reduced? Existing reported conflicting results. (3) what is the reason causing friction and wear performance is improved? Researchers have found that the introduction of second kinds of transition metal film can improve the friction and wear properties, but the mechanism is not the same. Some people think that H3/E2 value plays a decisive role, others attributed to oxide.2. introduction of metal silver. (1) the introduction of silver to transition metal nitride in silver content was less than 30 at.%, but the effect of high content of silver on the structure and properties of the films are rarely reported. (2) and the introduction of transition metals compared to the introduction of silver on the film structure and evolution to improve the performance on the impact and different? In view of the above problems, we use the co sputtering technique to hafnium nitride films were introduced into tantalum and silver, Hf-Ta-N films and Hf-Ag-N films with different compositions were prepared. By using X ray diffraction (XRD), Raman spectroscopy, transmission electron microscopy (TEM) characterization of phase structure by X ray photoelectron spectroscopy (XPS), X ray diffraction (EDS) analysis of thin film samples, using the Holzer test electrical properties, using scanning electron microscopy (SEM), optical microscopy, Nano Indenter and profilometer and friction wear tester etc. characterization of the friction and wear properties. The study found that: 1. both the content of Ta (x=Ta/ (Hf+Ta+N)) to change, Hf-Ta-N films have a solid solution structure. The conductivity by adding Ta in HfN films can improve the HfN film, this is attributed to the increase of electron concentration. This study found that, when x=0.03, the electrical conductivity of Hf-Ta-N thin films the (8.3 x 105 Sm-1 maximum, respectively) is pure HfN (4.9 * 105 Sm-1) and TaN (1.6 x 105 Sm-1) 1.7 times and 5.2 times. In addition, the introduction of appropriate Ta can reduce the wear rate and friction coefficient of the film, this is attributed to the increase of H/E and H3/E2 induced resistance to plastic film The deformation ability is enhanced, so that the wear resistance of the film increased. This study found that, in x=0.37, the wear rate (1.2 x 10-6 mm3/Nm) and friction coefficient (0.50) reached the minimum value, respectively, only pure HfN (11.6 * 10-6 and 0.65 mm3/Nm) and TaN (2.5 x 10-6 and 0.55 mm3/Nm 10%) and 77%, 49% and 91%.2. with the content of Ag (x=Ag/ (Hf+Ag+N)) increased, Hf-Ag-N film experience structure evolution of two stages: stage (I) when 0 x0.039, film is a solid solution of the rocksalt phase; (II) when x = 0.039 ~ 1, silver rich phase precipitation that film is a solid solution and silver rich phase coexisting structure. The introduction of Ag can improve the conductivity of HfN thin films and the friction and wear properties. This study found that, with x increased from 0 to 1, the film conductivity from 3.22 * 105 Sm-1 continuously increased to 33.1 x 105 Sm-1, which may be attributed to the introduction of Ag caused increase the electron concentration, and high content of Ag The film has the characteristics of metal Ag. When x=0.171, tribological properties of the optimal, the wear rate (0.54 x 10-6 mm3/Nm) and friction coefficient (0.38) compared to the pure HfN (16.7 * 10-6 and 0.62 mm3/Nm) were decreased by 96.8% and 38.7%, which is attributed to the interaction of solid solution strengthening of Ag and low shear strength degree. In addition, these results indicate that the alloying transition metal nitride is to improve the conductivity and friction and wear properties of the effective method. Compared with Hf-Ta-N films, the structure of Hf-Ag-N thin films changed from solid solution to the phase separation; the enhancement of conductivity are attributed to the Ag than the Ta has higher electron concentration that is more beneficial to improve the conductivity of the film; and the friction and wear behavior was improved by the combined effect of H3/E2 induced increase of film resistance to plastic deformation and enhance the ability of Ag low shear strength.

【学位授予单位】：吉林大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TB383.2

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