薄膜物理课件

2015 Fall USTC 翟晓芳 xfzhai Thin Film Physics 参考书 参考书 ThinThin Film Deposition Principles Film Deposition Principles and Practice by Donald L Smith McGrawand Practice by Donald L Smith McGraw Hill IncHill Inc Chapters 1 Introduction to thin film technology 2 Gas kinetics 3 Vacuum technology 4 Evaporation 5 Deposition 6 Thin film deposition methods 7 Electron photon and neutron techniques for examining surfaces and thin films 8 Thin film device processing 9 Contemporary thin film research and applications Chap 1 Introduction 1 1 Applications 1 2 History 1 3 Process step 1 4 Examples 1 1 Applications Why thin film Thin films are deposited onto bulk materials substrates to achieve properties unattainable or not easily attainable in the substrates alone What properties are required for the application at hand Typical applications Reflective antireflective coatings Memory disks Interference filters Waveguides Metamaterials Insulation Conduction Semiconductor devices Piezoelectric drivers Memory discs Barriers to diffusion or alloying Protection against oxidation or corrosion Gas liquid sensors Hardness Adhesion Micromechanism MEMS Barrier layers Heat sinks Thin film property category Optical Electrical Magnetic Chemical Mechanical Thermal Thin films discussed in this lecture are 1 from vapor phase deposition 2 contrary to thick films Comparison between thin and thick films Thin films deposition of single molecules Thick films deposition of particles i e painting spin on glass coating plasma spraying Advantages of thin films control of deposition material quality Comparison between vapor phase and liquid phase deposition techniques Liquid phase deposition low cost such as electroplating from liquid solutions Vapor phase deposition applicable to any material adjustable substrate temperature access to surface during deposition 1 2 History 1817 Fraunhofe 德国 将玻璃放入酸性溶 液中做实验 偶然的机会中 他发现玻璃表面 会生成一层薄膜 这层薄膜可以减少玻璃的 反射光 也就是抗反射Anti Reflection AR 1839 宾夕法尼亚大学教授Hare是第一个研 究电力应用的学者 他展示了水银阴极的电 解方法 电弧电焊 电极熔接等方法 这些方法 在数十年后 都成为重要的工业工程技术 1852 W R Grove 是第一个研究溅射现象的人 后来 这个技术发展成为所谓的 溅镀镀膜 Grove 使用一 个金属线的尾端靠近抛光过的银金属表面 形成一个 电路的电极 通电后 镀出一个环状的金属膜层 1858 Julius Plucker 注意到在放电管中会生成铂金 属膜层 这个铂膜层是一个很漂亮的金属镜 1887 Nahrwold 和 Kundt 在真空环境中 利用热升华产生 铂金属薄膜 他们也是首次研究真空环境与镀膜关系的人 不过直到1930年 真空技术还不成熟 真空环境很难创造并 应用在镀膜生产上 1924 Stokes 发明回旋活塞式真空帮浦 1933 Strong 使用细丝状的铝钯材和热蒸发沉积方法 产 制薄膜 O Brian Skinner 使用间接性的电子束蒸发方法 取代传统的热蒸发方式 1936 A Smakula 蔡斯公司 成功使用低折射率靶材 氟化 物 利用蒸发方式在真空腔体内 镀制一层AR抗反射层 这 是首次正式的商业化真空镀膜 1940 M Ruhle首次使用电子枪蒸发镀膜 来产制薄膜 1943 发明真空气体测漏仪 1946 Friedman 和 Birks 发明X射线的薄膜量测厚度技术 Vacuum Electronic Equipment Company VEECO 成立 1948 美国OCLI Optical Coating Laboratory Inc 成立 Dufour 发明利用光穿透率监控薄膜厚度的技术 Harris 和 Siegel 发明闪燃蒸发技术 Lander 和 Germer 发明现代工业化的CVD制程技术 开启 CVD新的制程时代 ECR plasmas 电子回旋共振式离子反应电浆发现 1958 NASA 成立 Pfeiffer 涡轮分子帮浦发明 1966 Vacuum Metallurgical Co ULVAC 成立 Physical Vapor Deposition PVD和 Chemical Vapor Deposition CVD名词被正式使用Powell Oxley Blockerr撰写的在气相沉积技术 Vapor Deposition 一书中 1972 溅镀沉积技术开始在真空腔体中使用离子 鎗 Tagaki发明离子束沉积技术 1983 Phillips 和 Sony 共同推出光盘 compac disk 产品 1 3 Process steps Source Transport Deposition and annealing Analysis Supply rate Uniformity Structure and composition Process modification Source solid liquid vapor gas Solid needs to be vaporized method Physical vapor deposition PVD Heat MBE thermal evaporation Electrons E beam evaporation Photons Pulsed laser ablation Positive ions Sputtering PVD Liquid and gas needs to be vaporized method Chemical vapor deposition CVD Common Issues contamination and supply rate Transport in vacuum gas fluid plasma Main issues uniformity of the arrival rate on the substrate In high vacuum molecules travel in a straight line often PVD Exceptions high pressure deposition of PLD and sputtering In gas liquid gas flow patterns diffusion of the source molecules often CVD Plasma can be either fluid or high vacuum medium Key points of deposition and analysis Deposition substrate condition reactivity of source materials energy input Analysis monitoring in real time of deposition rate and film crystallography Example 1 Microfabrication There s Plenty of Room at the Bottom by Dr Richard Feynman Some of the main ideas of Feynman s talk were The electrical equipment won t simply be scaled down They won t run hot because the heat escapes away from such a small device very very rapidly It would be interesting in surgery if you could swallow the surgeon You put the mechanical surgeon inside the blood vessel and it goes into the heart and looks around Two 1 000 prizes that have been increased to 250 000 for building two nanotechnology devices a nano scale robotic arm a computing device that demonstrates the feasibility of building a nanotechnology computer An integrated pressure sensor 3mm 3mm Accelerator sensor sensing region is 754 657 m2 Microfabrication 1 Optical contact lithography 2 Optical projection step and repeat lithography 3 Wet chemical etching 3 1 Isotropic etch 3 2 Anisotropic etch 4 Dry etching 4 1 Vapor etch 4 2 Plasma assisted etch 4 3 Deep reactive ion etch 5 Lift off Example 2 Metamaterials A metamaterial is an artificially structured material which attains its properties from the unit structure rather than the constituent materials A metamaterial has an inhomogeneity scale that is much smaller than the wavelength of interest and its electromagnetic response is expressed in terms of homogenized material parameters 参考书 Optical Metamaterials by Wenshan Cai Valadminir Shalaev 科学家透过高能X光 详细分析蒙娜丽莎脸 上不同层次的颜料排列及成份 科学家发现 画作共享了40