Cu、Ti纳米薄膜原位纳米压痕力学性能表征

发布时间：2018-01-09 15:00

本文关键词：Cu、Ti纳米薄膜原位纳米压痕力学性能表征　出处：《太原理工大学》2017年硕士论文　论文类型：学位论文

【摘要】：21世纪以来,随着能源、信息、环境、生物技术以及国防工业的迅猛发展,对纳米薄膜科学领域的研究也不断深入。在微机电系统(MEMS)中铜薄膜由于其较低的电阻率和较高的熔点,代替了以前互连线中的铝薄膜。钛薄膜以其良好的附着力、生物相容性而广泛应于太阳能电池、传感器、分解水制氢、贮氢材料以及生物科学等领域。然而近几年,元器件的小型化、智能化、高集成、高密度存储和超快传输等要求纳米薄膜材料的尺寸越来越小,要求纳米薄膜材料的性能越来越高。随着纳米科学领域研究的不断深入,对纳米薄膜材料的探索也逐步由观测样品表面形貌延伸到了力学性能等特征参数的获取领域。由于力学性能是纳米薄膜材料的重要基本性能参数,人们非常迫切的需要了解纳米薄膜材料在微观条件下和宏观力学性能之间的联系和区别,并希望得到相应的理论数据来指导新结构的设计。但是针对纳米薄膜力学表征的研究却很少见,随着纳米薄膜技术的不断发展,纳米薄膜力学势必将成为力学研究领域中不可或缺的重要组成部分,也是将来我们要深入研究的重要领域,其结果对纳米薄膜材料的使用起着非常重大的指导性意义。载荷压入曲线好比材料的指纹,由此可以得到相应纳米薄膜材料的力学性能指标。在本文中主要对铜纳米薄膜和钛纳米薄膜的力学特性参数通过纳米压痕法进行测试,以弹性模量为主要研究对象,采用自主研发的扫描电子显微镜/扫描探针显微镜(SEM/SPM)联合测试系统以及布鲁克原子力显微镜(AFM),通过纳米压痕的试验方法,得到被测试样品的力位移曲线,并通过赫兹理论计算得到其弹性模量。研究的主要内容及成果如下:1.利用自主研发的扫描电子显微镜-扫描探针显微镜联合测试系统,研究了直流磁控溅射(DCMS)和原子层沉积(ALD)两种成膜方式对40,60,80纳米铜薄膜弹性模量的影响。基于赫兹理论和King模型的计算结果表明,利用DCMS得到不同厚度铜薄膜的弹性模量值在95±2GPa到125±4GPa之间,而通过ALD得到的铜薄膜弹性模量值在99±2GPa到154±6GPa之间。对比分析可知,不同厚度的铜薄膜弹性模量比块体铜材料的弹性模量(90GPa)大6%-71%,且通过两种不同方式沉积得到的铜薄膜弹性模量值都随着薄膜厚度的增加而减小,表现出明显的尺寸效应。而且对于同一厚度的铜薄膜,利用ALD沉积的弹性模量比DCMS的大4.2%-23.2%,由透射电子显微图像对比分析可知,前者的平均晶粒尺寸是后者的60%,纳米晶粒小尺寸效应可能是薄膜弹性模量增大的原因。2.采用DCMS在(100)方向的硅片上沉积厚度为60nm、90nm、120nm以及180nm的钛薄膜作为实验的研究对象,并以布鲁克AFM为测试工具,纳米压痕为实验方法,复合弹性模量为指导,分别进行实验并求出不同厚度的钛纳米薄膜的弹性模量值。实验结果表明:厚度为60-180nm的钛薄膜弹性模量在95-132GPa之间。对于同一厚度的钛薄膜,弹性模量均随着峰值力的增加而减小,即随着压入深度的增加而减小;其中在不同峰值力的测试条件下,厚度为120nm钛薄膜测得的弹性模量相差最大(12.0%),厚度为60nm的相差最小(3.9%)。而且不同厚度的钛薄膜,在峰值力同为100nN的情况下,随着薄膜厚度的增加,其弹性模量逐渐减小;峰值力为150nN时同样如此。同时采用SEM/SPM联合测试系统对钛纳米薄膜进行压痕实验,得到的样品的弹性模量同样随着薄膜厚度的增大而减小。
[Abstract]:Since twenty-first Century, with the energy, information, environment, the rapid development of biological technology and defense industry, research on the scientific field of nano film deeply. In microelectromechanical systems (MEMS) in copper films due to its low resistivity and high melting point, instead of the previous interconnection in aluminum thin film titanium film to. The good adhesion, biocompatibility and widely applied in solar cell, sensor, the decomposition of water to hydrogen, hydrogen storage materials and biological sciences. However, in recent years, the miniaturization, intelligent components, high integration, high density storage and super fast transmission required size of nano film materials more and more small, requirements the performance is more and more high. The nano film materials with nano science research fields deepening exploration of nano film materials gradually from the observation sample surface extends to the mechanical properties and other characteristic parameters by Take the field. The mechanical performance is an important basic performance parameters of nano film materials, the relationship and difference between people is very urgent need to understand the nano film materials between under microscopic and macroscopic mechanical properties, and hope to get the corresponding theoretical data to guide the design of the new structure. But the study on nano mechanical characterization of thin films is very rare with the continuous development of technology, nano film, mechanical nano film is bound to become an important part in the field of mechanics, we are also important areas of research in the future, it plays a very important guiding significance for the use of nano film materials. The load curve of materials like fingerprints, which can be obtained the mechanical performance of the nano film materials. In this paper the copper nano thin film and nano titanium film mechanical properties parameters Tested by nanoindentation, the elastic modulus is the main research object, scanning electron microscopy / using self-developed scanning probe microscope (SEM/SPM) combined with Brook test system and atomic force microscopy (AFM), through the test of nano indentation method, get the force displacement curve of the sample is tested, and the elastic modulus obtained by Hertz theoretical calculation. The main research contents and achievements are as follows: 1. by using the scanning electron microscope and scanning probe microscope combined test system of DC magnetron sputtering (DCMS) and atomic layer deposition (ALD) effect of two kinds of film of 40,60,80 nano copper film elastic modulus calculation. Hertz theory and King model based on the results of the use of DCMS, the elastic modulus of different thickness of copper film in 95 + 2GPa to 125 + 4GPa, and the copper film elastic modulus obtained by ALD value In 99 + 2GPa to 154 + 6GPa. Comparing the different thickness of the copper film elastic modulus ratio of elastic modulus and bulk copper material (90GPa) 6%-71%, and the elastic modulus of copper thin film deposition in two different ways to get the value decreases with the increase of film thickness, showing obvious size effect. And for the same thickness of the copper film, the elastic modulus of ALD deposition is larger than that of DCMS 4.2%-23.2%, from the analysis of transmission electron microscopic image contrast, the average grain size of the former is 60% of the latter, nano crystal small size effect may be the reason for the increasing of.2. thin film elastic modulus used in DCMS (100) deposition the thickness of silicon wafer is 60NM, 90nm, 120nm and 180nm titanium film as the research object of this study, and to Brook AFM for testing tools, nano indentation method, composite elastic modulus as the guide, the experiment is carried out And calculated the elastic modulus of the nano titanium thin films with different thickness values. The experimental results show that the thickness of titanium film elastic modulus of 60-180nm in 95-132GPa. For titanium thin films with the same thickness, elastic modulus increased with the peak stress decreases, which decreases with increasing indentation depth; the peak force in different the test conditions, the thickness of 120nm titanium film measured elastic modulus was maximum (12%), the minimum thickness difference of 60NM (3.9%). And the different thickness of the titanium film, in the same peak force is 100nN, with the increase of film thickness, the elastic modulus decreases gradually; the peak force is 150nN when the same. At the same time by indentation experiments of titanium films were combined with SEM/SPM test system, the elastic modulus of the sample obtained by the same decrease with the increase of film thickness.

【学位授予单位】：太原理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TB302.3

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