桌面掃描電子顯微鏡高壓控制系統(tǒng)設計
發(fā)布時間：2019-01-20 10:10
【摘要】：隨著科學技術的發(fā)展與進步,掃描電子顯微鏡不斷往高分辨率、多功能、便攜小型化方向發(fā)展。近年來,我國的掃描電子顯微鏡有了一定的發(fā)展,但是同國外相比,我國在掃描電子顯微鏡的研制方面技術相對薄弱,制造出的掃描電子顯微鏡在穩(wěn)性定、可靠性、分辨率等方面與國外相比還有不小差距,特別是在桌面掃描電子顯微鏡研制方面,我國尚處于起步階段,因此桌面掃描電鏡的研制有著十分重要的意義。桌面掃描電子顯微鏡具有體積小巧、操作簡便、放大倍數大、分辨率高、抽真空迅速、不用噴金測量不導電樣品等特點。目前,主要以美國FEI公司推出的Phenom系列桌面掃描電子顯微鏡和日本日立公司推出的TM系列桌面掃描電子顯微鏡為代表占據著世界的主導市場。與國外的大公司相比,國內桌面掃描電子顯微鏡的研發(fā)還是空白,一直依賴進口。因此,加快國內自主品牌桌面掃面電子顯微鏡的研發(fā),對于打破國外壟斷、滿足國內市場需要,具有重要意義。本論文主要介紹了在企業(yè)研究生工作站,結合企業(yè)的產品研發(fā)項目,著重研究設計桌面掃描電子顯微鏡中的高壓控制系統(tǒng)。本論文的設計內容主要分為兩個方面,一是高壓控制系統(tǒng)的硬件電路設計,主要介紹了嵌入式控制模塊、數模轉換模塊、電子束流檢測模塊、加速電壓控制模塊、燈絲電壓控制模塊、升壓和倍壓電路模塊、燈絲電源模塊等設計；二是高壓控制系統(tǒng)的軟件設計,主要介紹了高壓控制系統(tǒng)的軟件架構、接口設計和主程序設計,而主程序設計又包括電壓信號產生程序設計和振蕩波程序設計。本設計主要是針對桌面掃描電子顯微鏡中高壓系統(tǒng)的小型化、低噪聲(適合辦公室使用)、可靠性高、快速、自動控制等特點進行設計。本論文的創(chuàng)新點如下：(1)設計采用STM32F103微控制器作為主控芯片,結合FPGA技術,完成對高壓系統(tǒng)的控制。(2)高壓發(fā)生器電路采用灌封膠灌封工藝,顯著的縮小了電路板體積,實現(xiàn)了高壓發(fā)生器小型、模塊、固態(tài)化。(3)采用高性能運算放大器OPA177,并采用負反饋放大電路實現(xiàn)了高壓的穩(wěn)定。(4)設計電子束流狀態(tài)異常判斷模塊,當電路或者真空異常時,系統(tǒng)能夠準確的判斷,并且及時的關閉高壓系統(tǒng)。
[Abstract]:With the development of science and technology, scanning electron microscope (SEM) has been developing towards high resolution, multi-function and portable miniaturization. In recent years, the scanning electron microscope (SEM) in our country has developed to a certain extent. However, compared with foreign countries, the technology of developing scanning electron microscope in our country is relatively weak, and the scanning electron microscope manufactured is stable and reliable. There is still a large gap between China and other countries in terms of resolution, especially in the development of desktop scanning electron microscope (SEM), which is still in its infancy in China, so the development of Desktop scanning Electron Microscopy (SEM) is of great significance. Desktop scanning electron microscope has the advantages of small volume, simple operation, large magnification, high resolution, rapid vacuum pumping, and no need of gold spray to measure non-conductive samples. At present, the leading market in the world is mainly represented by Phenom series desktop scanning electron microscope and TM series desktop scanning electron microscope introduced by FEI Company of USA and Hitachi Company of Japan. Compared with large foreign companies, domestic desktop scanning electron microscope research and development is still blank, has been dependent on imports. Therefore, it is of great significance to accelerate the research and development of domestic independent brand desktop scanning electron microscope to break foreign monopoly and meet the needs of domestic market. This paper mainly introduces the design of high voltage control system in the desktop scanning electron microscope (SEM) based on the product research and development project of the enterprise graduate workstation. The design content of this paper is divided into two aspects: one is the hardware circuit design of the high voltage control system, mainly introduces the embedded control module, the digital-to-analog conversion module, the electronic beam current detection module, the acceleration voltage control module. Filament voltage control module, voltage boost and voltage doubling circuit module, filament power module and other design; The second is the software design of the high voltage control system, which mainly introduces the software architecture, interface design and main program design of the high voltage control system, and the main program design includes the voltage signal generation program design and the oscillation wave program design. The design is mainly aimed at the miniaturization, low noise (suitable for office use), high reliability, fast and automatic control of the high voltage system in the desktop scanning electron microscope. The innovations of this paper are as follows: (1) the STM32F103 microcontroller is used as the main control chip and the FPGA technology is used to control the high voltage system. (2) the high voltage generator circuit adopts the technology of sealant filling and sealing. Significantly reduced the size of the circuit board, the realization of a high-voltage generator small, modular, solid-state. (3) the use of high-performance operational amplifier OPA177, The negative feedback amplification circuit is used to realize the stability of high voltage. (4) the module for judging the abnormal state of electron beam is designed. When the circuit or vacuum is abnormal, the system can judge accurately and close the high voltage system in time.
【學位授予單位】：南京師范大學
【學位級別】：碩士
【學位授予年份】：2015
【分類號】：TN16;TP273
本文編號：2411944
[Abstract]:With the development of science and technology, scanning electron microscope (SEM) has been developing towards high resolution, multi-function and portable miniaturization. In recent years, the scanning electron microscope (SEM) in our country has developed to a certain extent. However, compared with foreign countries, the technology of developing scanning electron microscope in our country is relatively weak, and the scanning electron microscope manufactured is stable and reliable. There is still a large gap between China and other countries in terms of resolution, especially in the development of desktop scanning electron microscope (SEM), which is still in its infancy in China, so the development of Desktop scanning Electron Microscopy (SEM) is of great significance. Desktop scanning electron microscope has the advantages of small volume, simple operation, large magnification, high resolution, rapid vacuum pumping, and no need of gold spray to measure non-conductive samples. At present, the leading market in the world is mainly represented by Phenom series desktop scanning electron microscope and TM series desktop scanning electron microscope introduced by FEI Company of USA and Hitachi Company of Japan. Compared with large foreign companies, domestic desktop scanning electron microscope research and development is still blank, has been dependent on imports. Therefore, it is of great significance to accelerate the research and development of domestic independent brand desktop scanning electron microscope to break foreign monopoly and meet the needs of domestic market. This paper mainly introduces the design of high voltage control system in the desktop scanning electron microscope (SEM) based on the product research and development project of the enterprise graduate workstation. The design content of this paper is divided into two aspects: one is the hardware circuit design of the high voltage control system, mainly introduces the embedded control module, the digital-to-analog conversion module, the electronic beam current detection module, the acceleration voltage control module. Filament voltage control module, voltage boost and voltage doubling circuit module, filament power module and other design; The second is the software design of the high voltage control system, which mainly introduces the software architecture, interface design and main program design of the high voltage control system, and the main program design includes the voltage signal generation program design and the oscillation wave program design. The design is mainly aimed at the miniaturization, low noise (suitable for office use), high reliability, fast and automatic control of the high voltage system in the desktop scanning electron microscope. The innovations of this paper are as follows: (1) the STM32F103 microcontroller is used as the main control chip and the FPGA technology is used to control the high voltage system. (2) the high voltage generator circuit adopts the technology of sealant filling and sealing. Significantly reduced the size of the circuit board, the realization of a high-voltage generator small, modular, solid-state. (3) the use of high-performance operational amplifier OPA177, The negative feedback amplification circuit is used to realize the stability of high voltage. (4) the module for judging the abnormal state of electron beam is designed. When the circuit or vacuum is abnormal, the system can judge accurately and close the high voltage system in time.
【學位授予單位】：南京師范大學
【學位級別】：碩士
【學位授予年份】：2015
【分類號】：TN16;TP273
【參考文獻】
相關期刊論文 前2條
1 陳翔;王叢嶺;楊平;廖理;;倍壓整流電路參數分析與設計[J];科學技術與工程;2012年29期
2 張德添;劉安生;朱衍勇;;電子顯微技術的發(fā)展趨勢及應用特點[J];現(xiàn)代科學儀器;2008年01期
，本文編號：2411944
本文鏈接：http://sikaile.net/kejilunwen/dianzigongchenglunwen/2411944.html
