低量程微型壓力傳感器研究

2.2萬字
自己的畢業(yè)設(shè)計(jì)，原創(chuàng)的，僅在本站獨(dú)家提交，推薦下載

摘要
傳感器技術(shù)是現(xiàn)代科學(xué)技術(shù)發(fā)展水平的重要標(biāo)志，是構(gòu)成現(xiàn)代信息產(chǎn)業(yè)的三大支柱之一。在各種傳感器中，硅壓力傳感器是應(yīng)用最為廣泛的一種，主要包括壓阻式、電容式和諧振式三種類型。目前應(yīng)用最廣泛的是壓阻式，其中主要是擴(kuò)散硅壓力傳感器，其擴(kuò)散電阻硅襯底之間是PN結(jié)隔離，但當(dāng)工作溫度超過120℃時(shí)，PN結(jié)漏電加劇，使傳感器特性嚴(yán)重惡化以至失效。
隨著MEMS中新工藝和新材料的出現(xiàn)，壓力傳感器向微型化和低量程發(fā)展，必須進(jìn)一步提高傳感器的靈敏度，在不增加壓力和芯片面積的情況下增加電阻上受到的應(yīng)力，即使膜應(yīng)力集中在電阻上。通常的做法是減小硅膜的厚度。但這樣做一方面難以在工藝上控制薄膜的厚度，增大不均勻性。另外，當(dāng)膜厚度小時(shí)，硅膜彎曲屬于大撓度的非線性彎曲，導(dǎo)致傳感器的非線性急劇增加，從而降低了測量精度，為了同時(shí)獲得較高靈敏度和較好的線性度，必須對硅膜結(jié)構(gòu)加以改進(jìn)，代替原來的PN結(jié)，提高耐高溫性能和穩(wěn)定性。本文開展微型壓力傳感器芯片的力學(xué)性能分析與研究，為微型高溫壓力傳感器的研究與開發(fā)提供理論依據(jù)。
關(guān)鍵詞：微型壓力傳感器 有限元 優(yōu)化設(shè)計(jì) 動(dòng)態(tài)特性 工藝流程

ABSTRACT
Sensor technology is important in the development of modern science and technology. It is one of three greatest technique of the information industry. Silicon pressure sensor is the mostly widely used among all the kinds of sensors, which includes piezo-resistive, capacitive and resonant sensors. At present, piezo-resistive pressure sensors are applied most widely, that mostly are made by form diffused strain gauges on the thin silicon diaphragm. This sensor uses isolation by reverse biased PN junction，whose junction leakage current rises at elevated temperature over 1200C， which deteriorate sensor characteristic so serious that it would disable the sensor.
With the emergence of new technology and new materials in MEMS industry， pressure sensor develops along the direction of microminiaturization and low range. In order to improve the device's sensitivity, the stress on the resistance must be increased at the same pressure and chip area，namely make the stress concentrate on the resistance. The usually used method is to reduce the thickness of silicon membrane. But on the one hand， it would be more difficult to control the thickness in process，and increase the uneven of thickness. On the other hand， when the thickness is very small, silicon membrane bending is the nonlinear bending of large deflection， resulting in sharp increase in nonlinearity,consequently reduces the accuracy of device. To obtain higher sensitivity and better linearity simultaneously，the structure of silicon diaphragm must be improved to replace original PN junction,to enhance the working temperature and stability. In this thiesis analysis and research on Mechanical properties of micro pressure sensor chip is to provide theoretical basis for the research and development of micro high temperature pressure sensor.
Keywords: Micro pressure sensor Finite element Optimum design Dynamic characteristics Process flow

目 錄
第一章 緒論 1
1.1 微機(jī)電系統(tǒng)簡介 1
1.1.1 微機(jī)電系統(tǒng)起源 1
1.1.2 微機(jī)電系統(tǒng)的特點(diǎn) 1
1.1.3 微機(jī)電系統(tǒng)國內(nèi)外發(fā)展現(xiàn)狀與趨勢 3
1.1.4 MEMS技術(shù)展望 4
1.2 微傳感器 5
1.2.1 微傳感器簡介 5
1.2.2 微傳感器研究現(xiàn)狀及市場前景 6
1.2.3 壓阻式壓力傳感器 8
1.3 耐高溫壓力傳感器 9
1.3.1耐高溫壓力傳感器的簡介 9
1.3.2耐高溫壓力傳感器國內(nèi)外發(fā)展現(xiàn)狀 10
1.4 本文的研究內(nèi)容 13
第二章 理論基礎(chǔ)與分析 14
2.1 總體結(jié)構(gòu)設(shè)計(jì) 14
2.2 彈性元件結(jié)構(gòu)初步設(shè)計(jì) 15
2.3 彈性元件結(jié)構(gòu)優(yōu)化設(shè)計(jì) 15
2.3.1 島直徑的大小對應(yīng)力值的影響 16
2.3.2 兩島中心距的變化對應(yīng)力值的影響 16
2.3.3 梁寬度的變化對應(yīng)力值的影響 16
第三章 薄膜應(yīng)力 17
3.1 薄膜應(yīng)力產(chǎn)生機(jī)理模型 17
3.2 薄膜應(yīng)力釋放機(jī)制 19
3.3 薄膜應(yīng)力控制技術(shù) 20
3.4 薄膜應(yīng)力測量技術(shù) 21
第四章 傳感器靈敏度 26
4.1 傳感器靈敏度的動(dòng)態(tài)標(biāo)定 26
4.2 超壓測試 27
4.2.1 測試系統(tǒng) 27
4.2.2 傳感器的安裝 27
4.2.3 測試結(jié)果 27
4.2.4 數(shù)據(jù)處理 28
第五章 壓力傳感器檢測電路分析 30
5.1 基于惠斯頓電橋的壓力傳感器 30
5.2 壓力傳感器的溫度誤差補(bǔ)償 30
5.3 壓力傳感器檢測電路分析 31
第六章 結(jié)論 34
致謝 35
參考文獻(xiàn) 36