國立台灣師範大學機電科技學系

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台灣師範大學機電科技學系 C. R. Yang, NTNU MT

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微微光機電系統與應用技術光機電系統與應用技術

Optical MEMS Technology and its application Optical MEMS Technology and its application

楊啟榮博士

教授

國立台灣師範大學機電科技學系

Department of Mechatronic Technology National Taiwan Normal University

Tel: 02-77343506 E-mail:ycr@ntnu.edu.tw

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Outline Outline

z Optical MEMS Devices

z Requirement for optical characteristics

z Microactuators for optical applications

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Optical MEMS Devices Optical MEMS Devices

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MEMS Applications for 21

MEMS Applications for 21 ^st ^st Century Century

z Optical MEMS

z Bio-MEMS

z RF MEMS

Comparative scale of semiconductor sensors.

μ-mechanical resonator for Frequency band 1MHz~1GHz

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Source: NEXUS III, http://nexus-mems.com/

Other are: microreaction, chip cooler, MEMS memories, liquid lenses, microspectrometer, **wafer probes, micro-mirrors for optical processing, micro-pumps*, micromotors, chemical** analysis systems*

*

(傾角計)

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MEMS market forecast from Yole Développement

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傳統的生化分析實驗室

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Artist impression of a hybrid

Artist impression of a hybrid μ μTAS dating from the mid 90's. TAS dating from the mid 90's.

全功能微分析系統全功能微分析系統

(micro total analysis system, (micro total analysis system, μ μTAS) TAS)

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1. Integration of bio-medical, chemical, optical,

electrical, mechanical, thermal, fluidic system on a chip 2. LOC (Lab on a chip), or μTAS (Micro total analysis

system) 3. Advantages:

a. fast response time b. automation

c. small sample quantity d. low cost

e. high throughput 4. Challenges

a. design and fabrication

b. high complexity of integration and package c. rare sample amount for detection

d. reliability

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生醫微機電系統生醫微機電系統

Blood testing Drug delivery

Insulin pump (Debiotech, Switzerland)

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Shrinking Wireless Architectures Shrinking Wireless Architectures

C. T.-C. Nguyen, “Communications applications of microelectromechanical systems (invited),”

Proceed-ings, 1998 Sensors Expo, San Jose, California, May 20, 1998, pp. 447-455.

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Source: http://jbyoon.info/

3D RF One

3D RF One- -Chip Module Chip Module

Integration of all passive components

^{極細同軸電纜}

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Micro Coaxial Cable (

Micro Coaxial Cable (極細同軸線極細同軸線) )

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MEMS

MEMS - - A New Enabling Technology A New Enabling Technology for Photonic Systems

for Photonic Systems

(效能接近的)

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Optical MEMS Components

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MEMS Micro Optical Bench MEMS Micro Optical Bench

M. C. Wu & H. Toshiyoshi, CNOM 8th Annual Affiliates Meeting

VCSEL (Vertical Cavity Surface Emitting Laser)(面射型雷射 )

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VCSEL stands for Vertical Cavity Surface Emitting Laser, is a semiconductor laser. That is laser-on-a-chip. VCSEL emits light in a cylindrical beam vertically from the surface of a fabricated wafer, and offers significant advantages when compared to the conventional edge-emitting lasers currently used in the majority of fiber optic communications devices.

What is VCSEL?

Conventional edge emitting laser VCSEL

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Micro Optical Bench Micro Optical Bench

(高低不平的,崎嶇的,粗糙的)

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R. S. Muller, Berkeley

Functional passive:

Mirror Engine:

Comb actuator

Transmission

Micro optical scanner

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Functional passive:

Mirror

Engine:

Comb actuator

Transmitting mechanism:

Linkage, gear

Sandia National Lab.

Micro optical scanner Micro optical scanner

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Answer : No more manual assembling Built in micro actuators to make 3-D structures Question :

Question : What is the most significant difference between conventional What is the most significant difference between conventional machining and micromachining.

machining and micromachining.

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Micro Elevated Self

Micro Elevated Self- -Assembling Assembling by Built

by Built- -in Actuators in Actuators

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H. Toshiyoshi

逐漸消失的

偏振器、極化器

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Filter Polarize - http://www.youtube.com/watch?v=MNzXrTKEMWg

Polarization (wave polarization) Polarization (wave polarization)

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Refraction Refraction

Fully assembled refractive micolens

300 μm

Ming C. Wu, UCLA

http://www.omminc.com/mems.html

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Solder self

Solder self- -assembly for MEMS assembly for MEMS

K. F. Harsh et al., Sensors and Actuators A, 77 (1999) 237–244

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-29- 台灣師範大學機電科技學系

C. R. Yang, NTNU MT

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2D Motion by Scratch

2D Motion by Scratch- -Drive Actuators Drive Actuators

可變聚焦位置透鏡可變聚焦位置透鏡

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Far Field Beam Profile (1.55 um) Far Field Beam Profile (1.55 um)

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Luke P. Lee, Berkley, 2002

http://www-biopoems.berkeley.edu/Project-first.php

Confocal

Confocal Microscope Microscope

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What is

What is confocal confocal? ?

In a confocal imaging system a single point of excitation light (from the first pinhole A) is focused onto a confocal spot (S) in the specimen. With only a single point illuminated, the illumination intensity rapidly falls off above and below the plane of focus as the beam converges and diverges, thus reducing excitation of fluorescence for interfering objects situated out of the focal plane being examined. Fluorescent light (i.e. signal) passes back through the dichroic reflector and then passes through the second (exit) pinhole (B), which is confocal with S and A. The exit pinhole can be made small enough that any light emanating from regions away from the vicinity of the illuminated point will be blocked by the aperture, thus providing yet further attenuation of out-of focus interference. A photomultiplier detector (PMT) provides a signal of the light passing scanned S1, S2, S3, S4, etc.(not shown), as the specimen is scanned. A computer is used to control the sequential scanning of the sample and to assemble the image for display.

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A

A confocal confocal imaging system imaging system

3D deconvolved blastocyst image

3D PMMA gear image

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Reflection Reflection

Electrostatic Combdrive-Actuated Micromirrors for Laser-Beam Scanning and Positioning

M. H. Kiang, et al., J. MEMS, 7, 27 (1998).

Vertical Scan Horizontal Scan

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H. Toshiyoshi, Hilton Head (2000), J. MEMS 10 (2001)

Electrostatically

Electrostatically Actuated MEMS 2D Optical Scanner Actuated MEMS 2D Optical Scanner

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3D Optical Scanner by Single Crystal 3D Optical Scanner by Single Crystal Si Si

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Free Space Integrated Optics Ming C. Wu, UCLA http://www.omminc.com/mems.html

Diffraction Diffraction

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Dynamic focusing microlens

http://www.omminc.com/mems.html M. Wu, et al., 1998

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(topside)

(a) Front side (b) back side of the grating

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The Grating Light Valve uses reflection and diffraction to create dark and bright image areas.

Grating Light Valve Grating Light Valve (GLV) (GLV)

Reflection and Diffraction

http://www.siliconlight.com/htmlpgs/glvtechframes/glvmainframeset.html Moving ribbon

Fixed ribbon

Air gap

Silicon Substrate

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當帶狀物沒有下移時，其表面形成一平面鏡面，可以將入射光直接反射回光源，此時為暗狀態。當pixel 被定址時，帶狀物會間隔下移而形成方井繞射光柵。藉由外加驅動電壓的變化，可以改變光柵的深度，如此可以在每一個pixel 控制光反射或光繞射的比例。

GLV 可以應用在數位模式或是類比模式。在數位模式中以其極快的切換速度達到灰階，pixel 的全開(fully on)及全關(fully off) 的速度遠快於人眼的辨識能力，並以開及關的時間比例控制灰階形成﹔在類比模式中，帶狀物無位移時是全關，當下移約1/4 入射光波長時，是為全開，帶狀物在全開與全關之間的位置，

控制灰階程度。

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A simple color display can be built using a single light source, single GLV, and rotating RGB filter disk.

An even simpler color display can be built with 3 LEDs (RGB) and a single GLV

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Silicon Light machines (SLM)的Grating Light Valve (GLV)技術(已轉賣給SONY)，其設計只要一維(1×1080)陣列，然後利用鏡面旋轉掃瞄構成二維(1920×1080)畫面，但其技術迄今仍未有成功的商品化。

http://www.sony.net/SonyInfo/News/Press_Archive/200206/02-023E/

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2 Parallel

2 Parallel- -plate plate Fabry Fabry- -Perot etalon tuned by translation movement Perot etalon tuned by translation movement http://www.ee.ucla.edu/labs/laser/index.html

Interference Interference

當光束通過具有高反射面鏡且腔長滿足半波長的整數倍時，穿透光有極大值

，形成陡削波形。當改變腔長或折射係數(腔體內含液晶)則可以使最大的穿透波長改變，而達到微調的功能。

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Fabry

Fabry- -Perot etalon Perot etalon interference interference

Fabry-Perot 干涉儀主要結構為由兩個具有高反射係數鏡面所形成的平行腔長

。當光行經兩個高反射係數鏡面所形成的平行腔長時，若腔長大小(d)滿足入射光的半個波長(l/2)的整數倍時(即2d = Nλ)，則產生建設性干涉而輸出陡峭的光波脈衝。

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Lucent, 1998 MARS

MARS – – Mechanical M echanical A A nti- nti -R Reflection eflection S Switch witch

Fully fabricated MARS device Si

Al

Ti/Au SiN

_x

Signal

Unbiased mλ/4 air gap (m odd -reflection)

Biased (m-1)λ/4 air gap (m even – anti-reflection)

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Optical MEMS Applications Optical MEMS Applications

Micro

Micro- -optical bench optical bench

http://www.ee.ucla.edu/labs/laser/index.html

z

Projection displays

z

Fiber switches

z

Filters and dispersion compensators

z

Optical scanners

z

Adaptive Optics

z

Silicon Optical Bench

z

Sensors with optical readout

z

Interferometers

z

Spectrometers

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Application of Optical MEMS Application of Optical MEMS

M. C. Wu & H. Toshiyoshi, CNOM 8th Annual Affiliates Meeting

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Integrated Free

Integrated Free- -Space Optical Disk Pickup Head Space Optical Disk Pickup Head

http://www.ee.ucla.edu/labs/laser/index.html

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Digital Mirror Display/Digital Light Processing Digital Mirror Display/Digital Light Processing

Texas Instruments 15 μm

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光通訊系統傳輸容量的進展光通訊系統傳輸容量的進展

l

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先利用數位或類比調變方式將資訊傳遞到發射機上，以雷射光為載波透過光纖傳播到遠方。若距離較長，可透過連接器(connector)或接合器(splice) 延長光纖傳送距離，最後以光感測器，把光訊號轉變回電訊號，將原傳送資訊解調回來。

光纖通訊基本架構光纖通訊基本架構

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訊號供應者

訊號接受者微光學透鏡

旁路開關多工傳輸器

接續器

陣列開關多光纖連接器

分光器多工傳輸解譯器

光通訊系統架構示意圖光通訊系統架構示意圖

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http://www.omminc.com/mems.html

Dynamic focusing microlens Deformable micro mirror

2 X 2 FDDI optical switch

Free Space Integrated Optics Rotating micro mirror

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輸入輸出

分波解多工器分波多工器

(a)光訊號作加成/消減(add/drop)示意圖；(b) OXC的架構示意圖

H. Toshiyoshi, Optical MEMS, UCLA, (2002).

Optical cross connector (OXC)

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分波多工

分波多工(Wavelength division multiplexing, WDM) (Wavelength division multiplexing, WDM)

傳統的光纖通訊，是採用單一載波波長傳輸資料。因為技術的演進，目前的光纖網路可有多個不同波長的頻道同時在一條光纖內傳遞資訊，稱為分波多工系統。在光纖網路系統中，把元件分成主動元件與被動元件：主動元件扮演收發以及放大訊號的工作，圖中Tx為發送器(transmitter)，Rx為接收器(receiver)，利用多工器

(multiplexer)，將各波道載波匯入同一條光纖傳輸，再利用解多工器(demultiplexer)

將光纖中多個波長的載波還原成個別波道的訊號。

發送器(transmitter) 接收器(receiver)

多工器解多工器

高密度分波多工

高密度分波多工(Dense wavelength division multiplexing, DWDM) (Dense wavelength division multiplexing, DWDM)

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DWDM基本原理如彩虹，多顏色合併後經光纖傳輸後分開波段光纖放大器

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Large scale optical cross connector (OXC) Large scale optical cross connector (OXC)

• E. L. Goldstein, J. A. Nagel, J. L .Strand, R. W. Tkach, "Multiwavelength opaque

optical-crossconnect network," Lightwave, Feb. 1998.

• M. C. Wu & H. Toshiyoshi, CNOM 8th Annual Affiliates Meeting

DWDM

DWDM WDM WDM- -D D

(復原 ) (路徑變化)

(增/減切換) (重配置 )

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Scanning Mirrors for OXC Scanning Mirrors for OXC

OXC: Optical Cross Connector

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MEMS in WDM Network MEMS in WDM Network

M. C. Wu & H. Toshiyoshi, CNOM 8th Annual Affiliates Meeting

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液晶(Liquid Crystal)一般用於顯示面板，其原理是利用外加電壓改變液晶的極態，藉由光線的偏極化(polarization)方向，再加上偏光板達到光的通過與否來做為畫面明與暗的效果。在光通訊開關方面，下頁圖為其主要應用原理的示意圖，利用光的偏極化特性，透過外加電壓改變液晶分子的指向來控制光的方向，整個切換過程只須少許電力。液晶技術應用在光開關產品方面，是適合中型尺寸(80 ports)的光開關，而由於液晶指向的改變速度不快，有研究發現將液晶加熱可降低其黏滯力 (viscous)，並提高其切換速度(switch speed)。

液晶(Liquid Crystal) 液晶 (Liquid Crystal)式光開關式光開關

-63- 未施加電壓

液晶分子

施加電壓液晶分子

液晶式光開關液晶式光開關

Spectraswitch Spectraswitch 液晶式光開關系統原理

液晶光開關圖例

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氣泡式的工作原理，主要是利用噴墨方式在交錯排列的波導 (waveguide)交點噴出氣泡，下頁圖為安捷倫(Agilent)的氣泡式核心技術示意圖，藉此改變光的路徑以達到輸出目的。目前安捷倫已與 Alcatel合作開發此技術，並已有32×32及32×16埠數的樣品，其切換速度約為10毫秒(msec)。但是氣泡式光開關須在密閉環境中操控，也就是必須在密閉環境中保持氣體與液體狀態共存的溫度及壓力，這也是目前氣泡式光開關在技術上所遭遇的困難。

氣泡(Bubble) 氣泡 (Bubble)式光開關式光開關

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氣泡式光開關氣泡式光開關

Agilent

Horizontal section of the planar lightwave circuit (PLC). Multiple optical paths consist of intersecting waveguides created into the PLC.

A trench is etched at each crosspoint of the waveguides.

Then the trench is filled with a fluid having the same optical properties.

When the optical signal needs to be redirected the fluid is heated up and a bubble is generated.

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As a default condition, the fluid enables the transmission of the light through the waveguide without changing it or deviating (偏離) it.

When the fluid is heated up the bubble created reflects the light by total internal reflection providing a fast switching function. The optical signal transmitted is deviated (偏離) but not deteriorated (惡化).

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全像術(Hologram)式光開關是對電致能布拉格光柵(electrically energized Bragg grating)施予電壓，配合一系列不同的折射常數材料來反射不同的特定波長，當外加一電壓時，布拉格光柵(Bragg grating)將光線折射到另一方向，未施加電壓時，光則直線通過。全像術式光開關除了光線切換功能之外，未被切換的光訊號可當作監視用訊號，具有動態光衰減器(dynamic optic attenuator)的功能。如下圖所示，上排的出口埠，可做為監視管理之使用。其最大的特色是光切換速度可達到奈秒級(nsecs)，也適合大規模的交換容量(上千埠)產品。有鑑以此，全像式光開關技術可能是未來在光路由器(optical routers)(其最主要的功用就是在不同的網路間選擇一條最佳的傳輸路徑)中使用光封包(packet)交換形式唯一可以支援的技術。

全像術全像術 (Holograms)式光開關 (Holograms) 式光開關

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全像術(Holograms) 全像術 (Holograms)式光開關式光開關

Trellis Photonics

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布拉格光纖光柵

布拉格光纖光柵(Fiber Bragg Grating , FBG) (Fiber Bragg Grating , FBG)

光源照射

光罩 光纖/波導

布拉格光纖光柵的製作是利用具有週期性結構圖案的光罩置於光纖上，再利用高能量短波長的紫外線照射後，可在光纖核心(core)部份產生干涉條紋，並永久地改變其折射率。當一個包含多個波長的光束經過FBG時，大部份波長的訊號只有些微損耗。但波長恰為光柵週期兩倍的光訊號會被反射回來。例如若反射波的波長是1550nm，光纖週期就是775nm。FBG的特性與三項因素有關:折射率差距、光柵部份的長度、製作的精密度。

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熱光

熱光(Thermo (Thermo- -Optical) Optical)式光開關式光開關

Singal input

Thermo-Optic Phase Shifter

1st SW 2nd SW

Output (Off State)

Output (On State)

熱光式光開關有兩種形式：(1) 干涉式(interferometric)熱光式光開關；(2) 數位式(digital)熱光式光開關。干涉式熱光式光開關主要設計原理是利用Mach Zehnder干涉型態，入射光線在輸入端被分為兩道，將其中一道加熱來改變其光行進距離(optical path length)，到了輸出端再加以組合，如下圖所示。利用兩道光行進距離的不同，造成破壞性及建設性干涉做為光的方向選擇，主要材料以矽土(Silica)為主。

NTT, Japan NTT, Japan

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聲光( 聲光 (Acousto Acousto -Optic, AO) - Optic, AO)式光開關式光開關

光源

聲波產生器

聲波轉折器

http://www.lmgr.net/aotechnology.htm 聲光式光開關的原理是利用聲波的疏密特性，來暫時改變物體的表面特性

，當光通過聲光偏折器時，會因為聲波造成表面特性的改變，使光線偏折角度不同而到達不同之傳輸目的地。

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各種光開關特性之比較各種光開關特性之比較

自行對位固定

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Requirement for optical characteristics Requirement for optical characteristics

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Reflectivity of Metals Reflectivity of Metals

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Coupling Distance of Fibers Coupling Distance of Fibers

GRIN lens fiber: graded-index lens fiber (漸變折射率透鏡式光纖)

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Collimated Beam Filter (Ball Lens)

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Source of the Insertion Loss Source of the Insertion Loss

Stability of Mirror Angle Stability of Mirror Angle

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光開關損失之原因光開關損失之原因

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Fiber Coupling Fiber Coupling

G-

G

-FF Fiber: Fluoride glass Fiber, Multimode, KDDFF Fiber: Fluoride glass Fiber, Multimode, KDD

TEC Fiber: Thermally Expanded Core Fiber

TEC Fiber: Thermally Expanded Core Fiber

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Microactuators

Microactuators for optical applications for optical applications

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Actuator is Energy Converter Actuator is Energy Converter

發冷光的,發光的光致伸縮效應

Ｓeebeck Effect:熱→電 Peltier Effect:電→吸放熱

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1984 1988

1989 1992

1993 1995

1997 1998 Comb-drive

W. Tang, et al.

Barcode scanner K. Y. Lau, et al.

MUMPs MCNC

Poly-Si beam R. T. Howe.

Micromotor Fan. Tai

Microhinge K. Pister

FS-MOB M. Wu

Raster-scanning MEMS display Fabrication platform

To use planar fabrication platform to make/integrate movable components on substrate

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Microactuators

Microactuators for Optical MEMS for Optical MEMS

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Downsizing Downsizing

Size reduction by MEMS technology

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What is expected out of MEMS for Optical Switch?

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MEMS Optical Switches MEMS Optical Switches

M. C. Wu & H. Toshiyoshi, CNOM 8th Annual Affiliates Meeting

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1x4 光纖定位光開關 1x4 光纖定位光開關光源輸入光纖

光源輸出光纖雙向定位光纖耦合

M. C. Wu, UCLA

Principles of Micro

Principles of Micro- -Optical Switch Optical Switch

2x2 微鏡面光開關 2x2 微鏡面光開關

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不同埠數之光開關示意圖

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MEMS Optical Switches MEMS Optical Switches

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Digital Matrix Optical Switch on a Chip Digital Matrix Optical Switch on a Chip

z

Toshiyoshi and Fujita, “Electrostatic micro torsion mirrors for an optical switch matrix,” J. MEMS, vol.5, p.231-7, 1996.

z

Lin, Goldstein, Tkach, “Free-space micromachined optical switches for optical networking. IEEE JSTQE, vol.5, p.4-9, 1999.

z

M. C. Wu & H. Toshiyoshi, CNOM 8th Annual Affiliates Meeting

-92- M. Hoffmann et al., JMM 9 (1999) 151

(24)

-93-

Switching cycle of a thermo-mechanical 1x2 moving-fiber switch

1 x 4 switch with coupled U-shaped actuator for large deflections

Photographs of a 1 x 4 switch

-94-

微反射鏡基本運動型式微反射鏡基本運動型式

(a) (b) (c)

(d) (e) (f)

-95-

Micro Elevated Self

Micro Elevated Self- -Assembling Assembling by Built

by Built- -in Actuators in Actuators

-96-

Schematic of the fabrication process for surface-micromachinined microhinges.

Surface Micromachining for

Surface Micromachining for Hinged structures Hinged structures

M. C. Wu, et al., Sensors and Actuators A, 50(1-2), 127 (1995).

http://www.coventor.com/media/papers/optical_SOI.pdf

(25)

-97-

Polysilicon

Polysilicon Hinge Structure Hinge Structure

K. S. J. Pister, M. W. Judy, S. R. Burgett, R. S. Fearing,

"Microfabricated hinges," Sensors & Actuators A33, 1992

-98-

Bell-Lab./ Lucent M. C. Wu, UCLA

M. C. Wu, UCLA

Mirror

Mirror- -typed Optical Switch typed Optical Switch

R. S. Muller, Berkeley

-99-

16 x 16 array Switch http://www.omminc.com/home.html

Mirror

Mirror- -typed 2D Optical Switch typed 2D Optical Switch

M. C. Wu, UCLA

-100-

(26)

-101-

Large Scale MEMS Optical Switches Large Scale MEMS Optical Switches

克勞斯(Clos)在1953年首先提出了「三級式網路」，這也是最基本的多級式交換網路 之一；假設 n 是一個輸入交換器的進線個數，克勞斯證明了這樣的網路只需要用到

2n-1 個中繼交換器，即能使得此網路達到絕對不阻塞。

引導

(N:輸入光纖的數目)

(兩個N面鏡負責引導光的方向) (Selector mirror + Router mirror)

-102-

3D Optical Switch 3D Optical Switch

(N: number of input fibers)

Selector mirror

Router mirror

Each mirror has N positions, total has N mirrors

-103-

Mirror

Mirror- -typed 3D Optical Switch typed 3D Optical Switch

Bell-Lab./ Lucent

-104-

http://www.omminc.com/home.html

Mirror

Mirror- -typed 3D Optical Switch typed 3D Optical Switch

Not movable

(27)

-105-

Scalability Scalability

串聯

分散

-106-

MICRO MIRROR SWITCH MICRO MIRROR SWITCH

Redirection of light beams by electrostatic torsion mirrors Redirection of light beams by electrostatic torsion mirrors

Where is actuator ? Where is actuator ?

H.Toshiyoshi, H. Fujita, IEEE J. MEMS 5(4), 1996.

H.Toshiyoshi, H. Fujita, IEEE/LEOS 96, Colorado.

D. Miyauchi, H.Toshiyoshi, H. Fujita, IEEE/LEOS MOEMS 97, Nara.

-107-

Electrostatic Torsion Mirror Matrix Electrostatic Torsion Mirror Matrix

Driving voltage is large.

-108-

Optical Switching Optical Switching

Collimated beam fiber (CBF)

(28)

-109-

Electrostatic Torsion Mirror Matrix Electrostatic Torsion Mirror Matrix

-110-

Electromagnetic theory predicts the ratio of the intensity of the reflected light to the intensity of the incident light. The polarization of the light with respect to the plane of reflection must be taken into account. There are two extreme cases: (1) the electric field is perpendicular to the plane of reflection, called Transverse Electric (TE), and (2) the magnetic field is perpendicular to the plane of reflection, Transverse Magnetic (TM).

These two cases are illustrated in the figure below:

TE and TM reflections. The dot shows the direction of the electric field in the TE case, and the magnetic field in the TM case.

-111-

Problems of Prototype Problems of Prototype

-112-

Torsion Mirror Electrostatic Operation

(29)

-113-

Operation Voltage Operation Voltage

H.Toshiyoshi, H. Fujita, IEEE J. MEMS 5(4), 1996.

Where G is set to the elastic constant of polysilicon, 73 GPa

-114-

Fabrication Process Fabrication Process

-115-

Bulk & Surface

Bulk & Surface Micromachinings Micromachinings

-116-

Electromagnetic Torsion Mirror Electromagnetic Torsion Mirror

○

(30)

-117-

Electrostatic vs. Electromagnetic Electrostatic vs. Electromagnetic

-118-

Electromagnetic Latching Electromagnetic Latching

No power consumption to hold mirror No power consumption to hold mirror

-119-

Cross Connector by Electromagnetic Torsion Mirror Cross Connector by Electromagnetic Torsion Mirror

-120-

UCLA's First Generation Switch UCLA's First Generation Switch

S. S. Lee, E. Motamedi, and M. C. Wu, 1997 Transducers Paper 1A4.07P, 1997.

(bit error ratio誤碼率) (鎖住) (彈出式)

(失效仍安全設計)

(31)

-121-

Electrostatic

Electrostatic S Scratch cratch- -D Drive rive A Actuator ctuator

Akiyama et al., IEEE J-MEMS, 1993, 1997

-122-

-123-

Automatic Self

Automatic Self- -Assembly by Curled Assembly by Curled- -up up Cantilever + Latch

Cantilever + Latch

H. Nguyen, R. Chen, M. C. Wu, UCLA, OSA-99

-124-

nm

R. Chen, H. Nguyen, M.C. Wu, IEEE MEMS Conference, 1999.

Curled Cantilever Switch Curled Cantilever Switch

(Polarization-dependent loss 極化相關損耗 )

(32)

-125-

2D Array of Curled Cantilever Switch 2D Array of Curled Cantilever Switch

-126-

Bulk micromachined actuators for N x N cross-connects.

Cross section of a wet-etched comb drive.

-127-

Spherical lens

fiber fiber

Source: A. Müller et al., J. Micromech. Microeng., 3 (1993) 158-160

Single-mode fibres adjusted to a ball lens Schematic of a microoptical switch with

single-mode fibres

Movable mirror and fibre grooves mirror

LIGA Process for Optical Switch LIGA Process for Optical Switch

-128-

Optical bench for alignment of fibers, lens and lasers

(33)

-129-

Micro-optical bench on top of a micromachined Si wafer Scheme of concept to fabricate optical bench by LIGA process

-130-

應用X 應用 X- -ray LIGA ray LIGA製程開發之光學陣列開關製程開發之光學陣列開關

J. Mohr, A. Last, and U. Wallrabe, 8th Microoptics Conference, Osaka, Japan, (2001).

-132-

Grating Light Valve (GLV)

(34)

-133-

GLV:1

GLV:1- -D Array type light valve D Array type light valve

-134-

The Grating Light Valve uses reflection and diffraction to create dark and bright image areas.

Grating Light Valve Grating Light Valve (GLV) (GLV)

Reflection and Diffraction

http://www.siliconlight.com/htmlpgs/glvtechframes/glvmainframeset.html Moving ribbon

Fixed ribbon

Air gap

Silicon Substrate

-136-

(35)

-138-

A simple color display can be built using a single light source, single GLV, and rotating RGB filter disk.

An even simpler color display can be built with 3 LEDs (RGB) and a single GLV

-139-

Typical gain equalizer module requiring multiple VOA devices, one per channel

-140-

An HDTV – resolution projector utilizing three GLV device optical attenuator modules A three GLV color display solution is

shown for a large-screen projector.

(36)

-141-

GLV Device Advantages:

When compared with more conventional optical MEMS technologies, Silicon Light Machines’ GLV technology

offers the following advantages:

1. Significantly faster operating speeds 2. High optical efficiency (low insertion loss) 3. Continuously variable attenuation that is highly

accurate and repeatable

4. Optical angular repeatability that is permanently set with photolithographic precision

5. No contact surfaces — high reliability and stability 6. Scalability to very large numbers of separately

國立台灣師範大學 機電科技學系

微 微 光機電系統與應用技術 光機電系統與應用技術

Optical MEMS Technology and its application Optical MEMS Technology and its application

楊 啟 榮 博士

教 授

國立台灣師範大學 機電科技學系

Department of Mechatronic Technology National Taiwan Normal University

Tel: 02-77343506 E-mail:ycr@ntnu.edu.tw

Outline Outline

z Optical MEMS Devices

z Requirement for optical characteristics

z Microactuators for optical applications

Optical MEMS Devices Optical MEMS Devices

MEMS Applications for 21

MEMS Applications for 21 st st Century Century

z Optical MEMS

z Bio-MEMS

z RF MEMS

Comparative scale of semiconductor sensors.

μ-mechanical resonator for Frequency band 1MHz~1GHz

Source: NEXUS III, http://nexus-mems.com/

*Other are: microreaction*, chip cooler*, MEMS memories, liquid lenses*, microspectrometer, wafer probes, micro-mirrors for optical processing, micro-pumps*, micromotors, chemical analysis systems*

*

*

*

*

*

MEMS market forecast from Yole Développement

傳統的生化分析實驗室

傳統的生化分析實驗室

Artist impression of a hybrid

Artist impression of a hybrid μ μTAS dating from the mid 90's. TAS dating from the mid 90's.

全功能微分析系統 全功能微分析系統

(micro total analysis system, (micro total analysis system, μ μTAS) TAS)

1. Integration of bio-medical, chemical, optical,

electrical, mechanical, thermal, fluidic system on a chip 2. LOC (Lab on a chip), or μTAS (Micro total analysis

system) 3. Advantages:

a. fast response time b. automation

c. small sample quantity d. low cost

e. high throughput 4. Challenges

a. design and fabrication

b. high complexity of integration and package c. rare sample amount for detection

d. reliability

生醫微機電系統 生醫微機電系統

Blood testing Drug delivery

Insulin pump (Debiotech, Switzerland)

Shrinking Wireless Architectures Shrinking Wireless Architectures

Source: http://jbyoon.info/

3D RF One

3D RF One- -Chip Module Chip Module

Integration of all passive components

Micro Coaxial Cable (

Micro Coaxial Cable (極細同軸線 極細同軸線) )

MEMS

MEMS - - A New Enabling Technology A New Enabling Technology for Photonic Systems

for Photonic Systems

Optical MEMS Components

Optical MEMS Components

MEMS Micro Optical Bench MEMS Micro Optical Bench

M. C. Wu & H. Toshiyoshi, CNOM 8th Annual Affiliates Meeting

VCSEL (Vertical Cavity Surface Emitting Laser)(面射型雷射 )

What is VCSEL?

What is VCSEL?

Conventional edge emitting laser VCSEL

Micro Optical Bench Micro Optical Bench

R. S. Muller, Berkeley

Functional passive:

Mirror Engine:

Comb actuator

Transmission

Micro optical scanner

Micro optical scanner

Functional passive:

Mirror

Engine:

Comb actuator

Transmitting mechanism:

Linkage, gear

Sandia National Lab.

Micro optical scanner Micro optical scanner

國立台灣師範大學機電科技學系

微微光機電系統與應用技術光機電系統與應用技術

楊啟榮博士

教授

國立台灣師範大學機電科技學系

MEMS Applications for 21 ^st ^st Century Century

Other are: microreaction, chip cooler, MEMS memories, liquid lenses, microspectrometer, **wafer probes, micro-mirrors for optical processing, micro-pumps*, micromotors, chemical** analysis systems*

全功能微分析系統全功能微分析系統

生醫微機電系統生醫微機電系統

Micro Coaxial Cable (極細同軸線極細同軸線) )

可變聚焦位置透鏡可變聚焦位置透鏡

Silicon Light machines (SLM)的Grating Light Valve (GLV)技術(已轉賣給SONY)，其設計只要一維(1×1080)陣列，然後利用鏡面旋轉掃瞄構成二維(1920×1080)畫面，但其技術迄今仍未有成功的商品化。

當光束通過具有高反射面鏡且腔長滿足半波長的整數倍時，穿透光有極大值

，形成陡削波形。當改變腔長或折射係數(腔體內含液晶)則可以使最大的穿透波長改變，而達到微調的功能。

。當光行經兩個高反射係數鏡面所形成的平行腔長時，若腔長大小(d)滿足入射光的半個波長(l/2)的整數倍時(即2d = Nλ)，則產生建設性干涉而輸出陡峭的光波脈衝。