【摘要】：壓力傳感器是微機(jī)電系統(tǒng)領(lǐng)域的重要器件之一,通過分析對比國內(nèi)外MEMS壓力傳感器的發(fā)展現(xiàn)狀,設(shè)計了基于犧牲層技術(shù)的SOI壓力敏感芯片。并針對汽車電子領(lǐng)域,對器件的結(jié)構(gòu)及參數(shù)進(jìn)行了優(yōu)化。首先,由于SOI材料是制作高溫壓力傳感器的良好材料,所以本文利用SOI技術(shù)完成壓力傳感器的設(shè)計。其次,基于壓力敏感結(jié)構(gòu)的有限元仿真結(jié)果,得知隨著膜片尺寸的改變,過載能力會有顯著的變化;過載能力的提升幅度和傳感器的量程有關(guān),量程越小,過載能力的提升幅度越大。結(jié)合敏感結(jié)構(gòu)的尺寸參數(shù)與過載能力之間的關(guān)系,可在保證傳感器靈敏度不變小的前提下,通過合理選擇敏感結(jié)構(gòu)尺寸提高過載能力。為使芯片體積小的同時電阻條所受的平均應(yīng)力盡可能大,根據(jù)單晶硅靈敏度高,重復(fù)性和穩(wěn)定性好的特點,設(shè)計單晶硅材料的應(yīng)變電阻,通過計算確定了采用彎折型電阻,每1/2電阻的長寬都為8μm。本文所設(shè)計的傳感器量程為0.5MPa,根據(jù)膜片尺寸和過載能力之間的關(guān)系,并結(jié)合電阻尺寸確定彈性膜片的長寬,彈性膜片的長度為200μm,寬度為100μm。經(jīng)線性靜力分析,確定了壓阻的布局,經(jīng)幾何非線性和接觸非線性分析,得到了膜片厚度的確定方法,并將膜厚設(shè)計為4μm。于是將腔體高度設(shè)計為0.3μm,最后采用1mA恒流源供電時,所設(shè)計的壓力敏感芯片靈敏度為178.74mV/Mpa,滿量程輸出為89.37mV,過載能力為12.21MPa。本文對基于犧牲層技術(shù)的SOI壓力敏感芯片進(jìn)行了設(shè)計和優(yōu)化,結(jié)構(gòu)尺寸的設(shè)計和電阻布局等使傳感器的各類參數(shù)均達(dá)到了預(yù)期的設(shè)計指標(biāo)。此外,本文基于犧牲層技術(shù)和SOI技術(shù),給出了壓力敏感芯片的工藝流程,并對工藝中的關(guān)鍵技術(shù)進(jìn)行了分析總結(jié),最后給出了本文傳感器的版圖設(shè)計,為傳感器的生產(chǎn)制造提供了設(shè)計方案。
[Abstract]:Pressure sensor is one of the important devices in the field of micro-electromechanical system. By analyzing and comparing the development status of MEMS pressure sensor at home and abroad, a SOI pressure sensor chip based on victim layer technology is designed. Aiming at the field of automobile electronics, the structure and parameters of the device are optimized. First of all, because SOI material is a good material for making high temperature pressure sensor, this paper uses SOI technology to complete the design of pressure sensor. Secondly, based on the finite element simulation results of pressure-sensitive structure, it is found that with the change of diaphragm size, the overload capacity will change significantly, and the increase range of overload capacity is related to the range of sensor, the smaller the range, the greater the increase range of overload capacity. Combined with the relationship between the size parameters of the sensitive structure and the overload capacity, the overload capacity can be improved by reasonably selecting the size of the sensitive structure on the premise of ensuring that the sensitivity of the sensor remains unchanged. In order to make the average stress of the resistance strip as large as possible when the chip size is small, according to the characteristics of high sensitivity, reproducibility and stability of single crystal silicon, the strain resistance of single crystal silicon material is designed. The bending resistance is determined by calculation, and the length and width of each 1 鈮，

本文編號：2500752