MEMS復(fù)習(xí)攻略

1、特此感謝：卓著、王明斗、蘭天翔、唐小濤、周孝吉對(duì)本攻略的貢獻(xiàn)。董建鵬 2015/1/14簡(jiǎn)述：1、只是包含MEMS中需要自己總結(jié)的內(nèi)容比較多的知識(shí)（除ppt6-7一些瑣碎的概念，其他章節(jié)部分需要總結(jié)的基本已涵蓋）。2、時(shí)間倉(cāng)促，做得可能不是很完善請(qǐng)諒解。3、英語水平有限，單詞語法錯(cuò)誤自己改正4、若有錯(cuò)誤或沒有涉及到的還望大家補(bǔ)充改正（英語）。5、.祝各位取得好成績(jī)！1. difference:MEMS is a process technology used to create tiny integrated devices or systems that combine mechanical

2、 and electrical components. NEMS is a great development of MEMS. Content: (1) Scale size (2) Material (3) Process technologyMEMSNEMSBasicmaterialSiliconCarbonMEMS NEMS Scale Size 1.Component:1um100um2.Device :0.1mm1mm 1nm100nm (4) Principle (5) Feature (6) Application (自己酌情刪減)MEMSNEMSProcess technol

3、ogy1.Miniaturized machine tool2.Wet etching3.Dryetching(RIE AND DRIE )4.Electro discharge machining(EDM):5.LIGA(X-ray)1.AFM/STM induced oxidation method2.Electron-beam lithography(>20nm)3.Atom or molecule assembly techniqueMEMSNEMSprinciple1.High power density (Micro-scale effect)2.Large surface

4、area to volume ratio makes surface effects dominant over volume effect. 3.Large thermal conductivity 1.Nano-scale effect 2.Quantum effect3.Interfacial effect MEMS NEMS feature1.Two dimension or quasi- Three dimension Structure 2.High precision 2-D control3.Integration mass production4.low power and

5、less inertia 1.Ultra-small dimension2.Ultra-high frequency Response(more than 100MHZ) 3.Ultro-low power MEMSNEMSApplication1.Targeted drug delivery system2.Miniature robot system 1.Biological motor2.Ultra-high frequency RF resonator 2. 擾動(dòng)執(zhí)行器的組成及其運(yùn)動(dòng)過程：Scratch Drive Actuator (SDA)（1）component：plate bu

6、shing insulator（絕緣體） substrate (2) processa） Applied voltage bends SDA downwardb) When released, SDA returns to original shapec) Reapplying voltage causes SDA to move a distance dx3. Pattern transfer（1）thin film on substrate Silicon dioxide is deposited as structural or sacrificial on the substrate

7、by PVD or CVD. （2）photoresist coatedResist typically 1 um. Spin resist always be used to achieve a uniform thin surface.（3）pattern photoresistWafer is transferred to an exposure system where it is placed between a photomask and exposed with an ultra violet radiation.（4）resist developmentThe photores

8、ist coated wafer undergoes development stage where selective dissolving of photoresist takes place.（5）etch of the thin filmThe silicon dioxide exposed on the air is etched by dry etching or wet etching. The silicon covered by the remained photoresist is saved.（6）resist stripplingRemove the photoresi

9、st.4. AlignmentThere are two kinds of Alignment(1) Alignment between multiple layers(2) Alignment between two sides of a wafer(1)Alignment for multiple layersFirst, we need alignment marks on both wafer and maskSecond, capture the image of the alignment mark of the mask in the microscopeThird, move

10、in the wafer and then see the alignment mask of the waferFourth, adjust the position of the wafer, so that the alignment marks of the wafer and mask match.This is how we do alignment for one-side alignment. Alignment for multiple layers means that you repeat this process every time when you add anot

11、her layer.(2) Alignment between two sidesThe situation is that we try to align the pattern on two side of a wafer. Lets say there are A side and B side. A side is already fabricated.First, move in the mask till we can see the alignment mark of the mask, and then restore this image in computer.Second

12、, move in the wafer with the B side towards the microscope. Third, adjust the position of the wafer, till the image of the alignment mark of the wafer match the alignment mark of the mask (the image in computer).之前我有和一些同學(xué)說對(duì)準(zhǔn)分為三種，即單面，雙面和多層，經(jīng)過討論改為兩種，只有雙面和多層。多層可看作單面的重復(fù)，故將二者合為一種。5. LIGA processLIGA原理：Pa

13、rt1. Resist moulding and 1st electroforming:Step1: Irradiation and DevelopingImplementing irradiation based on the resist and subsequently achieving the resist structure.以光刻膠（Resist）為基底，進(jìn)行光刻。此例中掩膜板(Mask membrane)是蜂窩煤狀，故形成的光刻膠結(jié)構(gòu)（Resist structure）亦是如此。Step 2: 1st electroforming and Removal of the resi

14、st structureElectroforming based on the resist structure, then stripping the mould and therefore obtain the final product.在光刻膠結(jié)構(gòu)(Resisit structure)上進(jìn)行電鍍，然后進(jìn)行脫模處理。脫模后的金屬結(jié)構(gòu)就是需要的最終產(chǎn)品（Final Product）。Part2. Plastic moulding and 2nd electroforming:Step1: Mould filling and Mould removalFilling the final pr

15、oduct with plastic, then separating them for the plastic mould.向最終產(chǎn)品中填注塑料，反求出塑料模型。分離并得到塑料模型。Step2: 2nd electroforming and Removal of the plastic mouldElectroforming based on the plastic mould, then stripping the mould and therefore obtain the final product.在塑料模型上進(jìn)行電鍍，然后進(jìn)行脫模處理，脫模后的金屬結(jié)構(gòu)就是需要的最終產(chǎn)品（Final

16、 Product）。Repeat Part2.Step2 and you will get more products.然后無限重復(fù)Part2.Step2,就可以獲得更多的最終產(chǎn)品。個(gè)人理解:很難將電鍍層（Mould insert）與光刻膠結(jié)構(gòu)完整分離，所以在第一次脫模的時(shí)候，我們用溶液將光刻膠結(jié)構(gòu)融化；再加上光刻膠本身容易磨損，導(dǎo)致光刻膠結(jié)構(gòu)只能是一次性的模型，不能重復(fù)使用。而在第二次脫模的時(shí)候，塑料模型是可以完整分離的，所以塑料模型是可以重復(fù)使用的模型，能夠投入生產(chǎn)中使用?？偠灾?，LIGA技術(shù)的目的就是做出一個(gè)傳統(tǒng)方法不易加工的（如例中的深孔），可重復(fù)使用的塑料模型，從而幫助我們進(jìn)行生產(chǎn)

17、?？荚囍苯映@些就可以了：Part1. Resist moulding and 1st electroforming:Step1: Irradiation and DevelopingImplementing irradiation based on the resist and subsequently achieving the resist structure.Step 2: 1st electroforming and Removal of the resist structureElectroforming based on the resist structure, then st

18、ripping the mould and therefore obtain the final product.Part2. Plastic moulding and 2nd electroforming:Step1: Mould filling and Mould removalFilling the final product with plastic, then separating them for the plastic mould.Step2: 2nd electroforming and Removal of the plastic mouldElectroforming ba

19、sed on the plastic mould, then stripping the mould and therefore obtain the final product.Repeat Part2.Step2 and you will get more products.6. 加速度傳感器（不考計(jì)算）（1） 種類 （2）機(jī)理 （3）構(gòu)造過程（用圖描述）(1) MEMS intertia sensors includes micro accelerometer and micro gyroscope. Micro accelerometer includes capacitive mic

20、ro accelerometer and piezoresistive micro accelerometer.(2) principle解釋：看ppt上的內(nèi)容有點(diǎn)一頭霧水，大家可以參考下下面的中文（得到慣性質(zhì)量塊的位移由此即可測(cè)得加速度，不過自我感覺還是沒有解釋清楚ppt的內(nèi)容，誰搞懂了可以上傳修正一下） （2） fabrication：piezoresistive micro accelerometer(自己寫的,可能很不完善請(qǐng)諒解，誰有這塊內(nèi)容望補(bǔ)充)(a) deposit silicon nitride at both sides of the silicon wafer.(b) De

21、posit 1st sacrificial layer polysilicon at the front side of silicon wafer and pattern the 1st payer(c) Deposit 2st silicon nitride at front side of silicon wafer and 1st silicon nitride at the back side of silicon wafer(d) Pattern 1st layer at the front side of silicon wafer and layer poly0 at the back side of the silicon wafer(e) Deposit and pattern metal layer (nickel)(f) Anisotropic etching to get the groove.Capacitive micro accelerometer:7. 陀螺儀（老師畫重點(diǎn)時(shí)沒