光波导显微技术测量微小厚度变化  

Thickness measurement of tiny change based on guided wave microscopy

作　　者：杜嘉斌[1] 刘选斌[1] 沈启舜[1] 朱鹏飞[1] 曹庄琪[1] 

机构地区：[1]上海交通大学物理系,上海200240

出　　处：《光电工程》2007年第2期32-36,共5页Opto-Electronic Engineering

基　　金：国家自然科学基金资助项目(60408010)

摘　　要：在表面等离子波显微技术(SPM)的基础上,提出了一种新的反射型波导显微理论,并且进行了实验研究。这种显微技术采用棱镜波导耦合结构,在棱镜下底面依次镀有金属膜-波导层-样品层。利用导模共振吸收峰对样品层厚度敏感的特性,通过反射光强的测量来确定样品层厚度的变化值。和表面等离子波显微技术相比,光波导显微技术所采用的波导结构能够有效地削弱金属的吸收特性造成的影响,减小衰减全反射曲线的半峰全宽,进而提高波导显微对厚度变化的灵敏度。实验表明,光波导显微技术对厚度变化有很高的灵敏度。A new type of microscopy is proposed by using the prism and asymmetrical metal-cladding polymer waveguide configuration. The structure consists of a coupling prism and 3-layer film coated on the bottom of prism in proper order. The 3-layer films are metal layer, waveguide layer and sample layer. Owe to the sensitive feature of sample thickness to the resonance absorption peak of the guided mode, the change of the sample thickness can be determined through the measurement of the light intensity. The experimental results show the high sensitivity of the proposed microscopy.

关 键 词：导波光学 衰减全反射 显微术 金属薄膜 

分 类 号：TN814[电子电信—信息与通信工程]