主题：PFM和AFM

怎么没有人理我啊,

The basic idea of Piezoresponse Force Microscopy (PFM) is to effect locally the piezoelectric sample surface by the electric field and to analyse resulting displacements of the sample surface[1].
The PFM technique is based on the converse piezoelectric effect, which is a linear coupling between the electrical and mechanical properties of a material. Since all ferroelectrics exhibit piezoelectricity, an electric field applied to a ferroelectric sample results in changes of its dimensions.
To detect the polarization orientation the AFM tip is used as a top electrode, which is moved over the sample surface. In the Intro1 animation one can see the reaction of out-of-plane and in-plane domains in the ferroelectric film on the voltage applied to the scanning tip in Contact Constant Force Mode. The electric field generated in the sample causes the domains with the polarization parallel to the field to extend and the domains with opposite polarization to contract.
If the polarization vector is perpendicular to the electric field, there is no piezoelectric deformation along the field direction, but a shear strain appears in the ferroelectric, leading to displacements of the sample surface parallel to itself, along the polarization direction.
The AFM probe tip moving according to the surface displacement causes cantilever normal or torsion (because of friction) deflections. Direction of the deflection depends on the mutual orientations of the electric field and domain polarization. Correspondingly in the case of the AC electric field  phase lag between the electric field and cantilever deflections will depend on the their mutual orientations. In general case by analyzing the amplitudes and phases of the normal and torsion cantilever vibrations one can reconstruct the sample domain structure.

我以前没做过跟AFM有关的样品,前几天去请教一个老师他那边的AFM是否能做PFM时,他一直在问我,PFM是用什么信号测,测出来的信号纵坐标是什么,我没做过,只是看有个别文献上只给出一张像形貌图一样的空间分布图,这个应该只是测得的原始信号经过转化后得到的实物图吧,所以我不知道PFM的原始信号是什么?麻烦大家帮我解答一下,谢谢!


还有,到底AFM和PFM有哪些区别,是不是AFM可以做PFM ,还是说PFM是构架在AFM上的一种扫描力显微镜,如果要做PFM,是不是还要配什么配件??

呵呵,我巧也做PFM,在清华做的,主要测压电系数d33.不知道你是干什么的?

真的吗?楼上的大侠只用PFM测过压电系数吗?


你看到这个贴可不可以给我发一封邮件啊,我想向你询问一下,可以吗?
我的邮箱:
sunnygirl-yf@sohu.com

十分感谢啊!

PFM是AFM的一种模式，可以看电畴

原文由 zhangkeming2008 发表:
呵呵,我巧也做PFM,在清华做的,主要测压电系数d33.不知道你是干什么的?

你好,能留下你的EMAIL或者QQ么?
我对D33测量比较有兴趣,想请教一下.或许我们可以合作下.我是南京大学物理系的研究生.
我的QQ;281641948
EMAIL:yikannju@gmail.com


(Piezoresponse force mode)PFM是(Scanning probe microscopy)SPM中的一种模式.是检测振幅相位信号的.可以同时观测电畴和表面形貌.我们的仪器是可以.

我们实验室有一台扫描探针显微镜，不过没有怎么发挥作用。我测过PFM模式，也看了一些文献，有报道这样一个公式Z（vibration）=d(zz)V(ac),通过这个公司可以计算压电系数。想请教一下，从PFM图上怎么得到Z（vibration）这个数据？还有测出的压电系数是什么方向的？十分感谢。我的Email：icanflyfreely@163.com

原理部分清风侠已经介绍得很清楚了，我补上一个与文字说明配套的Flash吧，这样便于大家理解。

原文由 ssh110 发表:
The basic idea of Piezoresponse Force Microscopy (PFM) is to effect locally the piezoelectric sample surface by the electric field and to analyse resulting displacements of the sample surface[1].

[~81197~]

怎么没看到呢