Mapping of Elasticity With Nano-Meter Resolution Using a Mass-Concentrated Cantilever in Atomic Force Acoustic Microscopy

在原子力声学显微镜中使用质量集中悬臂以纳米级分辨率绘制弹性图

基本信息

批准号：
14550065
负责人：
MURAOKA Mikio
金额：
$ 2.05万
依托单位：
Akita University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2002
资助国家：
日本
起止时间：
2002 至 2003
项目状态：
已结题

项目摘要

Near-field acoustic microscopy such as atomic force acoustic microscopy (AFAM) is a promising technique of imaging and evaluating such local elasticity. In AFAM, the resonant frequency of a micro-cantilever equipped with a sensor tip gives a measure of the contact stiffness between a sample and a tip. For stiff samples like metal and ceramics, AFAM is confronted with significantly low sensitivity. A mass-concentrated (MC) cantilever proposed by Muraoka gives an ideal solution for the problem.This study refined the technique of MC cantilevers so as to work stably without abrupt failures of its functions. The results are summarized as follows :1.Small amplitudes of the cantilever are recommended so that many parasite resonant peaks are depressed.2.Ductile coating such as Ti/Pt prefers for the tip rather than brittle coating like W_2C. The latter is very hard but easily delaminated. In contrast the ductile coating prolong the lifetime of the tip.Quantitative evaluation of elasticity using MC cantilevers also was discussed in this study.3.A flat-ended tip greatly simplifies the evaluation. The contact area is kept constant with the contact stiffness independent of the adhesion force and the contact force. The present method using a MC cantilever and a flat-ended tip gives a good evaluation with less than one percent of error for standard samples, diamond and etched Si wafers, having well-defined elastic coefficients for its surface, layers.4.The MC cantilever and a flat-end tip also demonstrated very sharp images reflecting sample elasticity for Co-Cr thin film in hard disks, PZT thin film, deposited carbon film, and Ti sheet. Fatigued surfaces of Ti sheets also were examined for nano-structures such as dislocation piling or slip bands.

近场声学显微镜，例如原子力声学显微镜（AFAM）是成像和评估这种局部弹性的有前途的技术。在AFAM中，配备有传感器尖端的微型委托人的谐振频率可衡量样品和尖端之间的接触刚度。对于金属和陶瓷等僵硬的样品，AFAM面临着明显较低的灵敏度。 Muraoka提出的质量浓缩（MC）悬臂为问题提供了理想的解决方案。这项研究完善了MC Cantilevers的技术，以便在其功能突然失败的情况下稳定工作。结果总结如下：1。建议使用悬臂的小幅度，以使许多寄生虫共振峰降低。2。d -ductile涂层（例如Ti/pt）更喜欢尖端，而不是像W_2C这样的脆性涂层。后者很难，但很容易被分层。相比之下，延长tip寿命的延展性涂层。在这项研究中还讨论了使用MC悬臂进行弹性的评估。3.一个平坦的尖端极大地简化了评估。接触区域保持恒定，接触刚度与粘附力和接触力无关。目前使用MC悬臂和扁平尖端的方法对标准样品，钻石和蚀刻的Si wafers的误差不到1％，其表面，层有明确定义的弹性系数。4。MC。悬臂和扁端尖端还显示出非常清晰的图像，反映了硬盘，PZT薄膜，沉积碳膜和Ti片的Co-Cr薄膜样品弹性。还检查了疲劳的Ti板表面，以进行纳米结构（例如脱位或滑动带）等纳米结构。