双脉冲电场及靶电流密度对TiN薄膜结构和性能的影响

发布时间：2018-06-01 09:59

本文选题：放电区间 + 双脉冲电场　；参考：《西安理工大学》2017年硕士论文

【摘要】：针对TiN薄膜现主流制备技术中,传统磁控溅射沉积粒子离化率低和多弧离子镀存在高温熔滴喷溅等技术不足,依据等离子体物理学中气体放电基础理论,通过构建双脉冲电场环境将气体放电引入辉光放电区和弧光放电区之间的强辉弱弧区间。利用该区间内具有的较大电场强度和电流密度的特性,增强正离子对阴极靶面的轰击强度和阴极靶材内部的焦耳热效应,诱发靶面沉积粒子以碰撞增强热发射方式脱靶,并获得较磁控溅射沉积粒子更高的离化率和更高的密度。同时,双脉冲电场模式所具有的阶梯式脉冲特性,不仅可利用前期弱离化阶段的原子电离降低后期强离化阶段的极间场强,并通过减少沉积粒子再次返回阴极靶面的几率以提升薄膜的平均沉积速率,而且还可利用前期弱离化阶段给予基体一定的离子轰击,增加后期强离化阶段沉积粒子在基体表面的扩散能,为制备出结构致密细化的薄膜提供了有利条件。本课题在不同伏安特性的放电区间制备三组TiN薄膜,同时在强辉弱弧区采用双脉冲电场在不同峰值靶电流密度下制备四组TiN薄膜,通过对薄膜的微观结构、力学、摩擦学及耐腐蚀性能的检测与分析,得到以下结论:相同靶功率条件下,双脉冲电场强辉弱引弧区制备的TiN薄膜相比直流电场辉光区制备的薄膜,具有较低的正反厚度比值(1.9)、接近的平均沉积速率(31nm/min)、较高的实时沉积速率(155.4nm/min)。由此说明利用双脉冲电场在强辉弱弧区可获得具有更高离化率和更高密度的沉积粒子。同时强辉弱弧区制备的TiN薄膜表面粗糙度为24nm,截面为柱状生长结构,改善了辉光区制备薄膜具有的疏松柱状结构,同时避免了弧光区由于高温熔融液滴的喷溅而造成薄膜具有较大的表面粗糙度(Rms=165nm)。通过对薄膜力学、摩擦学和耐腐蚀性能的研究发现:采用双脉冲电场模式在强辉弱弧区制备的TiN薄膜表现出27GPa的显微硬度,309GPa的弹性模量,19N的膜基结合力,以及1.4425×10-141m3/N·m的比磨损率,同时腐蚀速率的值为0.003mmm/a。利用双脉冲电场在不同峰值靶电流密度下制备多组TiN薄膜。通过对薄膜微观结构的研究发现:当峰值靶电流密度为0.87A/cm2时制备的薄膜具有颗粒细小致密的表面形貌和柱状的截面形貌。通过对薄膜力学、摩擦学和耐腐蚀性能的研究发现:随着峰值靶电流密度的增加,TiN薄膜的硬度从10.2GPa ( 0.27A/cm2 )增加到29.5GPa(0.87A/cm2)。平均摩擦系数和磨损率分别从0.9和1.383×10-13m3/N·m (0.27A/cm2)减小到0.67和2.7×10-15m3/N·m (0.87A/cm2)。腐蚀电流密度和腐蚀速率分别从3.4×10-8 A/cm2 和 1.78×10-4mm/a (0.27A/cm2) 减小到1.1×10-8A/cm2 和 5.52×10-5mm/a(0.87A/cm2)。
[Abstract]:In the mainstream preparation technology of TiN thin films, the low ionization rate of the traditional magnetron sputtering particles and the high temperature droplet splashing in the multi arc ion plating are insufficient. According to the basic theory of gas discharge in the plasma physics, the gas discharge is introduced into the glow discharge region and the arc discharge region by constructing the dual pulse electric field environment. The weak arc interval, using the characteristics of the larger electric field intensity and current density in the interval, enhances the bombardment intensity of the positive ion to the cathode target and the Joule heat effect inside the cathode target, induces the target surface deposited particles to be off target with the collision enhanced thermal emission, and obtains a higher ionization rate and higher density than the magnetron sputtering deposited particles. At the same time, the step pulse characteristics of the double pulse electric field model can not only reduce the interpolar field intensity in the late stage of strong ionization by atomic ionization at the early weak ionization stage, but also improve the average sedimentation rate of the film by reducing the probability of returning the deposited particles to the cathode target to improve the average sedimentation rate, and also can be used in the early stage of the weak ionization stage. A certain ion bombardment is given to the matrix to increase the diffusion energy of the deposited particles on the substrate at the late stage of strong ionization. It provides a favorable condition for the preparation of a thin film with dense structure. Three groups of TiN films are prepared in the discharge range of different volt ampere characteristics. At the same time, two pulse electric fields are used in the strong weak arc region at different peak target current density. By measuring and analyzing the microstructure, mechanics, tribology and corrosion resistance of the four groups of TiN films, the following conclusions are obtained: under the same target power, the TiN films prepared by the double pulse electric field and weak arcing zone have a lower ratio of positive and negative thickness (1.9) to the films prepared by the DC electric field. The average deposition rate (31nm/min) and higher real time deposition rate (155.4nm/min). Thus, it is indicated that the deposition particles with higher ionization and higher density can be obtained by double pulse electric field in the weak arc region of the strong glow. The surface roughness of the TiN thin film prepared by the weak arc region of the strong glow is 24nm, the cross section is columnar growth structure, and the preparation of the glow area is improved. The membrane has a loose columnar structure and avoids the larger surface roughness (Rms=165nm) of the film due to the splash of high temperature molten droplets in the arc region. Through the study of the film mechanics, tribology and corrosion resistance, it is found that the TiN thin film prepared by the double pulse electric field mode in the strong weak arc region shows the microhardness of 27GPa. The modulus of elasticity of 309GPa, the film based bonding force of 19N, and the specific wear rate of 1.4425 x 10-141m3/N. M at the same time, the value of the corrosion rate is 0.003mmm/a. using double pulse electric field to prepare a multi group of TiN thin film under the different peak target current density. It is found that the hardness of TiN films increases from 10.2GPa (0.27A/cm2) to 29.5GPa (0.87A/cm2) with the increase of the peak target current density. The average friction coefficient and wear rate are 0.9 and 1.383 * 10-13m3/, respectively. N. M (0.27A/cm2) decreases to 0.67 and 2.7 x 10-15m3/N. M (0.87A/cm2). Corrosion current density and corrosion rate are reduced from 3.4 x 10-8 A/cm2 and 1.78 x 10-4mm/a (0.27A/cm2) to 1.1 x 10-8A/cm2 and 5.52 * 10-5mm/a (0.87A/cm2).
【学位授予单位】：西安理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TB383.2

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