【摘要】：電容式加速度計(jì)因具備結(jié)構(gòu)設(shè)計(jì)簡(jiǎn)單、性能好、精度高、功耗低、易制作等優(yōu)點(diǎn)而被普遍研究。本論文設(shè)計(jì)了一種基于硅-玻璃陽(yáng)極鍵合加工工藝的電容式雙軸加速度計(jì)和一種Z軸加速度計(jì)。論文相關(guān)工作分為五部分展開(kāi):首先,在第一部分中簡(jiǎn)要介紹了MEMS相關(guān)方面的基礎(chǔ)知識(shí)以及當(dāng)前MEMS加速度計(jì)在國(guó)內(nèi)外的研究現(xiàn)狀。第二部分闡述了加速度計(jì)的相關(guān)工作原理和數(shù)學(xué)模型的建立,根據(jù)牛頓第二力學(xué)可以將加速度計(jì)簡(jiǎn)化為敏感質(zhì)量-阻尼-彈簧構(gòu)成的系統(tǒng)。通過(guò)對(duì)此系統(tǒng)的分析得出了加速度計(jì)的一些技術(shù)指標(biāo)如機(jī)械靈敏度等。其次對(duì)各類加速度計(jì)的原理進(jìn)行闡述,并且對(duì)比分析了電容式加速度計(jì)的兩種不同的檢測(cè)方式:變間距式和變面積式。變間距式檢測(cè)方式可獲得高靈敏度、高性能等優(yōu)點(diǎn),在實(shí)際結(jié)構(gòu)設(shè)計(jì)中使用較多。根據(jù)各種類型結(jié)構(gòu)的優(yōu)缺點(diǎn)確定最終選用電容變間距式加速度計(jì)作為文章主要研究結(jié)構(gòu)。其次,在文章第三部分給出了本論文設(shè)計(jì)的兩種電容式加速度計(jì)的具體結(jié)構(gòu)和參數(shù)。主要包括梁結(jié)構(gòu)的分析、整體結(jié)構(gòu)的設(shè)計(jì)以及交叉耦合性能的理論分析。之后使用商用軟件ANSYS對(duì)設(shè)計(jì)結(jié)構(gòu)進(jìn)行理論仿真和驗(yàn)證:通過(guò)力學(xué)分析得到了加速度計(jì)在工作范圍內(nèi)是線性的,及其在不同軸向上的機(jī)械靈敏度S_x=0.0845μm/g、S_y=0.1382μm/g和S_z=0.262μm/g。通過(guò)結(jié)構(gòu)強(qiáng)度分析論證了所設(shè)計(jì)的結(jié)構(gòu)具有良好的抗沖擊性能。在大沖擊(1000g)之下,結(jié)構(gòu)的最大應(yīng)力337.18MPa、457.34MPa和349.26Mpa出現(xiàn)在支撐梁和敏感質(zhì)量的連接點(diǎn)上,其值均在硅材料極限應(yīng)力1.3GPa的范圍之內(nèi)。最后通過(guò)模態(tài)分析得到了結(jié)構(gòu)的前四階的工作頻率,結(jié)構(gòu)前兩階為工作模態(tài),和其他模態(tài)相比,工作模態(tài)的頻率很小,因此能夠消除其他方向上的運(yùn)動(dòng)對(duì)檢測(cè)方向上的影響。之后依照設(shè)計(jì)的加速度計(jì)的結(jié)構(gòu)結(jié)合常用的MEMS加工技術(shù),設(shè)計(jì)了相對(duì)應(yīng)的工藝流程并且詳述了具體工藝步驟、工藝中需要注意的問(wèn)題以及相關(guān)步驟中涉及的工藝參數(shù),最終加工制得加速度計(jì)樣品,通過(guò)對(duì)比樣品的顯微照片及電鏡掃描結(jié)果和理論參數(shù)對(duì)比驗(yàn)證結(jié)構(gòu)合理性。文章最后部分設(shè)計(jì)了電容式加速度計(jì)相對(duì)應(yīng)的電路,對(duì)電路各部分的原理及設(shè)計(jì)進(jìn)行了闡述以及對(duì)加工制備的加速度計(jì)樣品進(jìn)行簡(jiǎn)單測(cè)試。
[Abstract]:Capacitive accelerometer has been widely studied because of its simple structure design, good performance, high precision, low power consumption, easy to fabricate and so on. In this paper, a capacitive biaxial accelerometer and a Z-axis accelerometer based on silicon-glass anode bonding process are designed. The related work of this paper is divided into five parts: firstly, in the first part, the basic knowledge of MEMS and the current research status of MEMS accelerometer at home and abroad are briefly introduced. In the second part, the working principle and mathematical model of accelerometer are described. According to Newton's second mechanics, the accelerometer can be simplified to a system composed of sensitive mass, damping and spring. Through the analysis of this system, some technical indexes of accelerometer, such as mechanical sensitivity and so on, are obtained. Secondly, the principle of all kinds of accelerometers is described, and two different detection methods of capacitive accelerometers are compared and analyzed: variable spacing type and variable area type. The variable distance detection method can obtain the advantages of high sensitivity and high performance, and is widely used in practical structural design. According to the advantages and disadvantages of various types of structures, the capacitance variable distance accelerometer is selected as the main research structure in this paper. Secondly, in the third part of the paper, the concrete structure and parameters of two kinds of capacitive accelerometers designed in this paper are given. It mainly includes the analysis of the beam structure, the design of the whole structure and the theoretical analysis of the cross-coupling performance. Then the commercial software ANSYS is used to simulate and verify the design structure: through mechanical analysis, it is found that the accelerometer is linear in the working range and its mechanical sensitivity S 鈮，

本文編號(hào)：2475061