高功率脉冲磁控溅射斜入射沉积氮化钛薄膜结构及应力调控研究

发布时间：2018-04-16 01:35

本文选题：高功率脉冲磁控溅射 + 斜入射沉积　；参考：《西南交通大学》2016年博士论文

【摘要】：采用磁控溅射技术在复杂形状工件表面沉积薄膜过程中,工件各表面与溅射靶之间存在不同角度,这造成了薄膜的斜入射沉积。在斜入射沉积过程中,阴影效应的产生将导致工件各表面薄膜厚度、结构及性能存在差异。在工件服役过程中,薄膜性能最薄弱的地方首先发生失效,最终缩短了工件表面薄膜整体的服役寿命。为了减小复杂工件各表面薄膜结构和性能的差异,增加工件各表面薄膜性能(包括应力、结构、硬度以及耐腐蚀性等)均匀性,通过控制薄膜沉积工艺来消除阴影效应显得十分必要。工作气压和基体偏压是薄膜沉积工艺中两个关键参数,在调控薄膜成分、结构及性能方面发挥着非常重要的作用。工作气压能用于改变溅射粒子的平均自由程和散射几率；基体偏压可用于改变基片附近电场的强弱并影响金属或气体离子的能量大小,进而改变溅射粒子飞行路径及到达基片时的入射方向。本论文针对复杂工件表面镀膜改性问题,在研究基片曲率法测试薄膜残余应力基础上,分别采用直流磁控溅射技术(DCMS)和高功率脉冲磁控溅射技术(HPPMS)在与溅射靶成不同倾斜角度的硅和不锈钢基体样品表面上沉积(斜入射沉积)氮化钛(TiN)薄膜,研究了工作气压和基体偏压等参数对倾斜于溅射靶的表面上沉积薄膜的结构和性能影响。在此基础上,采用交替变换溅射角度的方法制备一种垂直生长柱状晶和倾斜生长柱状晶的多层薄膜结构(“类之字形”薄膜结构)来调控TiN薄膜应力,研究了多层薄膜中倾斜生长柱状晶薄膜层的厚度对TiN薄膜应力、硬度及抗磨损性能影响。最后,为改善复杂工件表面沉积薄膜的均匀性,在高功率脉冲磁控溅射技术(HPPMS)制备TiN薄膜过程中,采用增加HPPMS脉冲宽度的方法来提高金属离化率,研究了脉冲宽度对(与溅射靶成不同角度的)倾斜表面上沉积TiN薄膜的结构、性能及均匀性的影响。本论文获得以下主要结论：(1)利用基片曲率法研究了Si(100)基片固定端和基片尺寸对薄膜应力测量的影响。研究结果表明,基片固定端在一定程度上约束了基片在应力作用下的变形,基片各位置处发生变形的难易程度不同,从而导致了基片变形不规则。当基片长宽比等于或大于3：1时,沿基片长度方向不同位置所测量的应力值基本一致。因此,采用基片曲率法测量薄膜应力时选用的Si片长宽比应大于等于3：1,且测量轮廓曲线时应沿基片长度方向进行。(2)采用DCMS在硅基体上斜入射沉积制备TiN薄膜,研究了基体偏压和工作气压对TiN薄膜结构和性能的影响规律。研究结果表明,当Si样品表面倾斜于溅射靶时,阴影效应便会产生,即TiN薄膜结构疏松且柱状晶倾斜于样品表面生长。提高基体偏压使得倾斜于靶的Si样品表面上沉积薄膜的致密性和硬度明显提高,但是,斜入射沉积过程中的阴影效应仍然存在,且无法从根本上得以消除。提高工作气压使薄膜结构变得疏松,阴影效应同样无法得到消除。(3)采用交替变换溅射角度的方法在硅和不锈钢基体上制备一种“类之字形”薄膜结构来调控TiN多层薄膜应力,研究了多层薄膜中倾斜生长柱状晶薄膜层厚度对不锈钢基体上沉积的TiN多层薄膜的应力、硬度及抗磨损性能影响。研究结果表明,“类之字形”结构能够有效地调控TiN多层薄膜应力,通过控制倾斜生长柱状晶薄膜层的厚度能够提高不锈钢基体上沉积的TiN薄膜硬度以及抗磨损性能。(4)研究了高功率脉冲磁控溅射技术(HPPMS)制备TiN薄膜过程中,工作气压和基体偏压等关键参数对阴影效应以及Ti、TiN薄膜结构和性能的影响。研究结果表明,提高工作气压,可以使溅射粒子在散射作用下更容易垂直到达与溅射靶倾斜的Si样品表面,从而使得Si基体上沉积的Ti薄膜的柱状晶垂直于样品表面生长,但其薄膜致密性及硬度明显下降,这说明高工作气压的采用也只是减轻了阴影效应。提高基体偏压,金属离子在强的电场作用下能够发生偏转以及在高的能量驱使下容易产生迁移,使得倾斜Si样品上沉积的TiN薄膜柱状晶垂直于样品表面生长且薄膜结构变得致密,从根本上消除了斜入射沉积过程中阴影效应,同时增加了离子的轰击作用,薄膜具有更大的压应力。(5)为了提高复杂工件表面沉积薄膜的均匀性,高功率脉冲磁控溅射技术(HPPMS)制备TiN薄膜过程中,通过提高HPPMS脉冲宽度的方法来增加金属离化率,研究了脉冲宽度对(与溅射靶成不同角度的)倾斜表面上(Si和不锈钢基体)沉积的TiN薄膜结构、性能及均匀性影响。研究结果表明,脉冲宽度的增加有利于提高金属离化率,同时提高基体偏压,更多溅射金属离子在电场作用(基体偏压)下能够垂直到达与溅射靶倾斜的表面,从而导致与溅射靶倾斜的样品表面上沉积TiN薄膜的致密性提高,最终,不同表面上沉积TiN薄膜的结构、硬度和耐腐蚀性能均匀性得以改善。
[Abstract]:By using magnetron sputtering technology in the process of complex shape workpiece surface deposition of thin films, there are different angles between the workpiece surface and the sputtering target, which caused the oblique incidence of the deposited film. In oblique incidence deposition process, shadow effect will lead to the workpiece surface film thickness, structure and performance difference. In the course of service the properties of the films, place the weakest first failure, and ultimately shorten the service life of the whole film surface. In order to reduce the fluctuation of the structure and properties of the complex workpiece surface film, increase the performance of the workpiece surface thin film (including stress, structure, hardness and corrosion resistance) uniformity, by controlling the deposition process to eliminate the shadow effect is very necessary. Working pressure and bias are two key parameters of thin film deposition process, the control of the film composition, structure and performance. Play a very important role. Working pressure can be used to change the mean free path of the sputtered particles and scattering probability; substrate bias can be used to change the substrate near the electric field strength and impact energy size of metal or gas ions, and then change the flight path and the sputtered particles. When the incident direction of Scientology for the modification of the complex the workpiece surface coating film on the substrate in the test of residual stress based on curvature method, respectively with DC magnetron sputtering (DCMS) technology and high power pulsed magnetron sputtering (HPPMS) at different angles of silicon and stainless steel sample surface deposition and sputtering target (oblique incidence deposition) of titanium nitride (TiN) the film, study the working pressure and bias parameters on structure and properties of thin films deposited on the surface of inclined sputtering target effect. On this basis, using alternating sputtering angle The invention relates to a method for preparing vertical columnar crystal and Inclined Multilayer Thin Films Growth of columnar crystal ("glyph" film structure) to stress regulation of TiN thin films, multilayer films in inclined columnar crystal film thickness on the stress of TiN thin film, hardness and abrasion resistance to impact finally, for improving the uniformity of complex workpiece surface thin film deposition, in high power pulsed magnetron sputtering (HPPMS) TiN thin film preparation process, by adding HPPMS pulse width to increase the ionization rate, the pulse width of (different angles and sputtering target) inclined structure deposition of TiN thin films on the surface, affecting the performance and uniformity. The main conclusions are as follows: (1) Si was studied by substrate curvature method (100) substrate fixed end and the size of the substrate stress measurement of thin films. The results show that the substrate in a fixed end The degree of constraint on the substrate during deformation under the action of stress, deformation at each position of the substrate in varying degrees of difficulty, resulting in irregular substrate deformation. When the base length width ratio is equal to or greater than 3:1, measured along the length direction of the substrate position of the stress value of a therefore, the substrate curvature method for stress measurement of thin films with Si length width ratio should be greater than or equal to 3:1, and the measurement curve should be carried out along the length direction of the substrate. (2) by DCMS on silicon substrate with oblique incidence deposition of TiN thin films, studied the influence of substrate bias voltage and working pressure on the structure and properties of TiN films. The results show that when the Si sample surface inclined to the sputtering target, shadow effect will occur, i.e. TiN thin film structure loose and columnar crystal tilt to the sample surface growth. Increase of substrate bias makes tilt to the target Si sample surface deposition The density and hardness of the film increased obviously, but the shadow effect of oblique incidence deposition process still exist, and can not be fundamentally eliminated. Improve the working pressure of the film structure becomes loose, the shadow effect also cannot be eliminated. (3) on silicon and stainless steel substrate for the preparation of a "zigzag" the film structure to control the TiN multilayer thin film stress by alternating sputtering angle, the stress of multi-layer films of inclined columnar crystal film thickness deposited on stainless steel substrate and TiN multilayer films, the hardness and abrasion resistance can influence. Research results show that the "zigzag" structure can effectively the regulation of TiN multilayer thin film stress, by controlling the inclined columnar crystal film thickness can improve the hardness of TiN films deposited on stainless steel substrates and anti wear properties. (4) research on the high power pulse magnet The technology of magnetron sputtering (HPPMS) TiN thin film preparation process, the key parameters of working pressure and bias of the shadow effect and Ti effect, structure and properties of TiN thin films. The results show that the increase of working pressure, can make the sputtered particles in the scattering more easily under the action of vertical to the sample surface Si and sputtering target tilt thus, Ti films deposited on Si substrate by columnar crystal growth perpendicular to the sample surface, but the film density and hardness decreased significantly, indicating that the use of high pressure is just to reduce the shadow effect. To improve the substrate bias, the metal ions can deflect and in high energy driven generating shift in under the strong electric field, the tilt of Si samples of TiN films deposited on the columnar crystal growth perpendicular to the sample surface and the film structure becomes more compact, fundamentally eliminate the effects of oblique incidence deposition process of Bardo At the same time, increase the ion bombardment, the film has greater compressive stress. (5) in order to improve the uniformity of thin film deposition complex workpiece surface, high power pulsed magnetron sputtering (HPPMS) TiN thin film preparation process, to increase the ionization rate by increasing the pulse width of the HPPMS. Study on pulse width (different angles and sputtering target) on inclined surfaces (Si and stainless steel) TiN thin film deposition, influence of performance and uniformity. The results show that the increase of the pulse width is beneficial to improve the ionization rate, while increasing the substrate bias, more sputtering of metal ions in the electric field (under the vertical bias) can reach the surface tilt and sputtering target, which leads to the compactness of the tilt and the sputtering target samples deposited on the surface of TiN films increased, eventually, TiN films were deposited on different surface structure, hardness and corrosion resistance The energy uniformity can be improved.

【学位授予单位】：西南交通大学
【学位级别】：博士
【学位授予年份】：2016
【分类号】：TQ134.11;TB383.2

【参考文献】