【作者】 彭平；

【导师】 史铁林； 廖广兰； 汤自荣；

【作者基本信息】 华中科技大学 ， 机械制造及其自动化， 2010， 博士

【摘要】 随着微纳米技术的飞速发展,微型化、集成化已成为了发展趋势。为了实现产品微小型化、降低成本、扩大生产效率的目标,需要不断研究探索微纳制造技术,推动其发展。原子力显微镜(Atomic Force Microscope, AFM)是一种纳米精度的表面形貌测量仪器,利用其纳米尺度的针尖对样品表面进行刻划,可以实现微细的切削加工,将图形转移到样品表面。为此,本文结合国家自然科学基金“具有气体检测功能的仿蝴蝶翅膀三维微纳结构制备技术研究”的需求,提出了一种基于AFM的微纳尺度模板加工技术,采用带有金刚石针尖的AFM切削加工铝薄膜材料,并结合感应耦合等离子刻蚀工艺制备出具有一定深宽比的微纳尺度模板结构,具体研究内容如下：1、微纳加工机理研究。建立了AFM金刚石针尖及薄膜衬底结构模型,采用分子动力学方法分别对纳米压入过程以及切削过程进行了仿真。分析了薄膜在被压入过程中载荷力变化,研究了衬底对载荷力及薄膜材料变形造成的影响。采用不同的载荷速度进行了纳米压入的仿真,得出了材料变形及材料硬度随载荷速度的变化规律。此外,还对AFM针尖不同的切削方向进行了仿真,分析了不同的前端面形状对切削结构及碎屑形成造成的影响,以及不同切削深度、切削速度对材料去除状态的影响,为加工实验提供了理论指导。2、详细讨论了基于AFM的微纳刻划加工系统的参数控制方法。研究了AFM加工沟槽过程中悬臂梁形变的测量方法,分析了AFM针尖的受力情况与探针悬臂梁的变形关系。在实验中采用横向位移补偿的方法消除了AFM弹性悬臂机械切削加工时产生的横向形变误差。实时测量了AFM针尖在加工过程中各方向受力的变化,为实施反馈控制提供了条件。3、提出了AFM探针加工单晶硅衬底上的光刻胶薄膜和铝薄膜的工艺步骤。实验研究了刻划力与加工深度之间的关系。研究了AFM切削加工时,加工深度、加工速度、沟槽间距对加工结果的影响。通过优化加工参数在薄膜衬底结构上制作了平行沟槽结构,结合感应耦合等离子刻蚀工艺制作了具有一定深宽比的亚微米结构模板。AFM加工是一项非常有前景的微纳制造方法。基于AFM的精密测量、微纳加工、纳米操纵、微纳结构修饰等都还在不断地研究和发展之中。本文针对AFM机械刻划加工和制作模板的应用进行了探索,基于AFM的应用研究更有待于进一步的深入和完善。更多还原

【Abstract】 Nanotechnology has become a rapidly growing field today. There is a tendency for product to become minimal and integrated. To achieve the goal of miniaturization, cost effect, and high yield of fabrication, constant progress and development of nanotechnology is needed. Finding novel fabrication methods with more efficient and lower cost is becoming a research hotspot. The invention of atomic force microscope (AFM) has provided a new method for micro/nano fabrication. AFM is an instrument to make a height image of a very small part of a surface by scanning the surface with a nano tip. AFM can also be a tool for sequential manufacture. In order to investigate the mechanism of micro/nano machining, based on the practical application of AFM fabrication, a new combined method of sub-micron high aspect ratio structure fabrication is developed which can be used for production of micro/nano template. The process includes AFM scratch nano-machining and inductively coupled plasma (ICP) fabrication. The main contents of this thesis are shown in the following.1. The mechanism of micro/nano fabrication is investigated. AFM diamond tip and film/substrate system is modeled; nano-indentation and nano-scratch processes are simulated using molecular dynamics simulation. The deformation of the film and substrate during the indentation process is analyzed. By using different loading speeds, the relationship between the hardness of the film and the loading speeds is studied. The scratch simulation is also carried out in different orientation. The effect of the front end face of AFM tip on the fabricated structure and the cutting chip is analyzed. The material removal affected by cutting depth is also studied. The study results provide guidance for AFM fabrication.2. The relationship between the deformation of the cantilever and the load force is investigated. The method for measuring the deformation of the cantilever during the AFM fabrication is studied. The real time forces on the AFM tip during the fabrication process are got by reading the output of the photo detector which provides condition for feedback control of the AFM fabrication process.3. The relationship between the scratch depth and the loading force is investigated by the experimental study. With optimized parameters, the structure of parallel grooves is fabricated on the Al film deposited on the single crystal Si wafer by AFM fabrication. Combined the AFM nano machining and the ICP etching process, a high aspect ratio structure of sub-micron template is fabricated.AFM micro/nano fabrication is a process with broad prospect. The study of precision measurement, micro/nano fabrication, nano manipulation and nano modification based on AFM are still in progress. The mechanical machining and micro/nano template fabrication based on AFM are studied in this dissertation, some other applications based on AFM fabrication need further study and improvement.更多还原