Scanning Electron Microscope Scanning Circuit And Image Acquisition Circuit Is Developed

As a useful tool for probing the microscopic world,scanningelectron microscope (SEM),invented in the late1980s,is one of the mostimportant scientific instruments and is widely applied in many fields.Indesigning high speed scanning electron microscope,not onlyadvanced electron optical design is need, precise machinery designand the cooperation from electronics and computer technology arealso required.Through adopting digital/analog convertor with highprecision and speed, high speed scanning technology becomespossible.The combination of high speed digital/analog convertor withfast data transmission allows real time display of the SEM image on thecomputer.In this thesis,based on the summarization of the relatedresearch in SEM, we design high speed image record circuit and highspeed signals generater circuit of SEM using high speed DAC and DAC.Both circuits are controled by the computer. The main points of thisthesis are summaried as follows:1. Analysis of the characteristic of SEM scan signals,designingthe scan circuit, writing the control programs and debug the circiut.2. Design of the image recorder circuit, writing the imagerecord and image data transmission softwave, debugging imagerecorder circuit.3. Design the image recorder circuits computer driver, writing ofthe image process and display program.