AFM-Raman System For The Experimental Study Of Micro/Nano-Scale Mechanics

Micro-Raman spectroscopy(MRS)and atomic force microscope(AFM)are regarded as effective methods of experimental mechanics at micro/nano-scale with the fast development of the scientific instruments in recent years.However,difficulties still exist in the accurate or precise mechanical measurements by using current instruments of MRS and AFM.Specially,because of their closed and fixed structures,it is difficult to inset mechanical loading devices/apparatuses into either MRS or AFM instruments.Meanwhile,various geometric and polarization configurations can't be provided for the experimental study on complex stress conditions.Therefore,this work presented an instrument investigation on a modularized MRS system,a full-opened AFM system and their combined system.A modularized MRS system was designed and established.Its observation path was used to illuminate and view the specimen using white light,and its laser path was used to excite and collect Raman signals.The whole optical sub-system was connected with the laser and spectrometer by using optical fibers.This system can not only perform Raman-mechanical measurement independently but also realize the combination with other system because of its compact structure,light weight and adjustable position.A series of calibration experiments were carried out and the results proved the good stability and accuracy of the modularized MRS system.A full-opened AFM was also developed in this work.The 3D image of the sample surface can be obtained by controlling the tip to scan along Z direction and specimen stage to scan along X and Y directions.The scanning results proved the accuracy of the device.In this AFM system,the space around and below the tip was full opened,without any other extended components,which make it possible to inset other apparatuses such as mechanical loading device and MRS.Base on the modularized MRS system and the full-opened AFM system above,some improved design and local optimization were performed,including the frame structure,the interventional angle and displacement mechanism of MRS.The combination of AFM-Raman system was finally realized.