Displays: Projection, Head Mounted - Virtual Reality. â Repro-graphics: .... 8x8 Fiber-optic switch 2. 2X2 Fiber-optic
STANFORD
OPTICAL MICRO-ELECTROMECHANICAL SYSTEMS (O-MEMS) J. S. Harris, Jr. Stanford University
O-MEMS APS Short Course 3/11/01
JSH-1
1
Outline STANFORD
l
Overview Advantages l Fundamentals l
l
Mechanical O-MEMS l l l
l
Semiconductor Optical Device O-MEMS l l l
l l
Optical Communications Network Switches Optical Bench Displays l Torsional Mirror l Grating Light Valve Tunable Laser Tunable Detector Modeling
MEMS Systems Examples Summary
O-MEMS APS Short Course 3/11/01
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What is O-MEMS STANFORD
l l
Optics l l l l
l
Reflective Refractive Diffractive Waveguiding
Semiconductor Devices l l
l
A Marriage of Three Technologies
Optoelectronic III-V Devices Si-CMOS Processing and Control Electronics
Semiconductor Based Micromachining l l l l
Lithography Deposition Epitaxy Etching
O-MEMS APS Short Course 3/11/01
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The Past Millennium STANFORD
Palomar Telescope
Tunable Laser
Optical Table
O-MEMS APS Short Course 3/11/01
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The New Millenium STANFORD
NASA Space Telescope
Monolithic Tunable Laser 4.3 m Active Laser Stripe
Semiconductor Edge-Emitting Laser
Pre-aligned Micro-Fresnel Lens
Optical Table 3D Structures Pre-aligned to the Lens
O-MEMS APS Short Course 3/11/01
JSH-5
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Integration System on a chip STANFORD
Laser-to-fiber coupling Micropositioners for mirrors and gratings High-resolution raster scanner
O-MEMS APS Short Course 3/11/01
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The Major Driving Force: Communications Link Capacity STANFORD
O-MEMS APS Short Course 3/11/01
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Advantages of O-MEMS “A Marriage of Technologies” STANFORD
l l l l
Small force required - Photons have zero mass Very small displacements required - /4 Precision displacement possible Based upon compatible semiconductor processing l l
l l l l l
Mass, low cost production Added functionality thru integration
Reduced size, weight, and cost Physically robust Reduced physical alignment - Photolithography High resonant frequencies Speed of light (no RC limitation)
O-MEMS APS Short Course 3/11/01
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O-MEMS: an Enabling Technology STANFORD
Communications: Fiber Switches. Femtosecond Lasers, Pulse Shaping, Modulators, Tunable Optical Devices l Optical Interconnects l Optical Data Storage l Displays: Projection, Head Mounted - Virtual Reality l
Repro-graphics: Printing, Scanners l Adaptive Optics l Optical Transducers and Sensors l Optical Spectroscopy and Instrumentation l
O-MEMS APS Short Course 3/11/01
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Fundamental Optical Functions STANFORD
Reflection
Refraction
Diffraction
Guiding
O-MEMS APS Short Course 3/11/01
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Active Device Functions STANFORD
Generation Laser
Modulation Mach-Zehnder
O-MEMS APS Short Course 3/11/01
Detection Photodiode
JSH-11
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O-MEMS Active Devices STANFORD
Generation VCSELs
Modulation QCSE Modulator
Detection Photodiode
All Active Devices are Surface Normal O-MEMS APS Short Course 3/11/01
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Technologically Available Optoelectronic Materials STANFORD
AlN 6.0
Bandgap energy (eV)
4.0
(.21 µm)
(.31 µm)
ZnS
GaN
3.0
Visible Spectrum
(.41 µm)
α–SiC
2.0
(.62 µm)
1.0
(1.24 µm)
MgSe ZnSe AlP
CdS
GaP
InN
CdSeAlSb GaAs
Si
GaSb
Ge
3.4
5.4
InSb
InAs
(Ge)
3.2
CdTe
InP
BULK
SLE
3.0
ZnTe
AlAs
5.6
5.8
6.0
6.2
6.4
Lattice Constant (Å) O-MEMS APS Short Course 3/11/01
JSH-13
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Optical Communications Material Choices STANFORD
2.5 AlAs
Bandgap (eV)
2
InxAl1-xAs
AlxGa1-xAs 1.5 GaAs
InP InxGa1-xAs
1
0.5
980nm InxGa1-xAsyP1-y
1300nm 1550nm
GaNyAs1-y GaxIn1-xNyAs1-y on GaAs
InAs InNyAs1-y
0 5.4
5.5
5.6
5.7
5.8
5.9
6
6.1
6.2
Lattice Parameter (Å)
●
GaNAs and GaInNAs have large bandgap bowing ● Long wavelength material lattice matched to GaAs
O-MEMS APS Short Course 3/11/01
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Surface Micromachining STANFORD
PolySi Nitride Oxide
Slider
Hinge
V-groove for alignment
Mirror
O-MEMS APS Short Course 3/11/01
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17
Principle of Operation STANFORD
l
Coupled Cavity: Air Gap + Semiconductor Cavity ∆d d0
d
V F=
l l
l l
∂W ∂ 1 2 0AV = CV = ∂z ∂z 2 2d 2
2
Electrostatic Force from applied voltage Balance between electrostatic and elastic restoring force: d ~ V2/d2 Effective cavity length: / 0 = d/d0 Light emission restricted to cavity modes
O-MEMS APS Short Course 3/11/01
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Design Issues: Mechanical Actuation Limit STANFORD
Force
V =V 3 crit V 4 V Electrostatic 2 V 1 Force (dotted) Increasing Voltage
0
Elastic restoring force (solid)
Membrane Displacement
d
d0
l
Nonlinear nature of Electrostatic Force
l
Stable solutions: displacement less than ~Lg0 / 3
O-MEMS APS Short Course 3/11/01
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MIRRORS STANFORD
Texas Instrument’s DMD NASA's Next Generation Space Telescope (2008) with 4M micromirrors by Sandia NL Lucent’s Optical X-Connect
O-MEMS APS Short Course 3/11/01
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Electrostatic-combdrive STANFORD
Folded beams (movable comb suspension)
x
Ground Comb Anchors plate drive
Electric field distribution in comb-finger gaps
O-MEMS APS Short Course 3/11/01
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actuators – Electrostatic Combdrives STANFORD
Springs Fiber grooves or channels
manipulator comb drives
Bryant Hichwa etal, OCLI/JDS Uniphase, “A Unique Latching 2x2 MEMS Fiber Optics Switch”, Optical MEMS 2000, Kauai, August 21-24 th, 2000.
O-MEMS APS Short Course 3/11/01
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Wavelength Switching Speed STANFORD Wafer 3976R2.1: 20 m Square Membrane
l -10V DC / 5
Bias conditions:
0V DC
l l
10 µs
Intensity (a.u.)
5 µs
4 µs 3 µs
l
2 µs
Constant 10mA Diode Current Membrane driven by square pulse, 500ns to 10 s variable pulse width, 10V Amplitude, 20% duty cycle
Time-averaged Spectrum:
1 µs
l
90% of average
shift in 1 s
500 ns
950 955 960 965 970 975 980 985 990
Wavelength (nm)
O-MEMS APS Short Course 3/11/01
JSH-23
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Micromirror Reliability “Off” position
1 0.5 0 -0.5 -1 0
10
20
30
40
50
60
measurement #
70 Change in Res. Frequency
Angle (degrees)
STANFORD
x 10-3
80 2.00% 1.50% 1.00% 0.50% 0.00% -0.50%
O-MEMS APS Short Course 3/11/01
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1.E+04
1.E+06 1.E+08 # of Cycles
1.E+10 JSH-24
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Outline STANFORD
l
Overview l l
Advantages Fundamentals
l
Mechanical O-MEMS
l
Optical Communications Network Switches Optical Bench l Displays l Torsional Mirror l Grating Light Valve Semiconductor Optical Device O-MEMS l l
l l l
l l
Tunable Laser Tunable Detector Modeling
MEMS Systems Examples Summary
O-MEMS APS Short Course 3/11/01
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WDM Crossbar Switch STANFORD
Input Ports
•• •
•••
1 2
λ1OXC λ2OXC
OXC λM
N
Output Ports 1 2 •••
Optical DMUX
Optical MUX
N
Architecture of WDM Switch The optical input signals are demultiplexed, and each wavelength is routed to an independent NxN spatial cross-connect O-MEMS APS Short Course 3/11/01
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O-MEMS Modulation Means STANFORD
Properties of Light: l Intensity, Wavelength, Polarization, and Phase Each of these can be modulated, although intensity is the most common mode
Modulation Means: Linear Motion l Deflection l Reflection l Diffraction l Interference l
O-MEMS APS Short Course 3/11/01
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2 x 2 fiber-optic switch STANFORD
§
Out 2
§
Out 1 §
In 1
In 2
§ § §
Compact design One-mask fabrication using DRIE on SOI Integration of fibers, lenses, and micromirrors 2 by 1 operation By-pass switch AT&T, JDSU.......
O-MEMS APS Short Course 3/11/01
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1 x 2 Matrix Switch STANFORD
O-MEMS APS Short Course 3/11/01
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MEMS-based OXC switches STANFORD
2X2 Fiber-optic switch
§
§ § §
2
2
Some issues: §
1
8x8 Fiber-optic switch
1
Switch scalability with minimum insertion loss Large device count Non-standard fabrication processes Actuator reliability problems
C. Marxer, N.F. de Rooij, Jrnl of Lightwave Tech., Vol. 17, No. 1, Jan 1999 L.Y. Lin, E.L. Goldstein, R.W. Tkach, Jrnl of selected topics in Quantum Electronics, Vol. 5, No. 1, Jan 1999
O-MEMS APS Short Course 3/11/01
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NxN Matrix OXC STANFORD
§
§ § § § §
Simple 1 by 2 cross-points Digital mirrors N2 scaling Large motion Reliability?? OMM, Onix, AT&T, Agilent.....
O-MEMS APS Short Course 3/11/01
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Beam Steering Optical Switch STANFORD
§ § s = N ?k 2 l § Output § fiber array
Analog mirrors 2N scaling Accuracy? Lucent, C-speed, Xros(NT),.....
Input fiber array
O-MEMS APS Short Course 3/11/01
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2x2 Beam Steering Switch* STANFORD
Input Mirror Array
M1
Input A
M2
Input B
Output A
M4 Output Mirror Array
*P.M. Hagelin, U. Krishnamoorthy, et. al, paper published in § § § § § §
O-MEMS APS Short Course 3/11/01
Output B
M3
Photonics Technology Letters, July 2000.
Silicon micromachined v-grooves 1.55 m diode laser source Comb-drive actuated mirrors Bulk optics for optical field scaling -4.2 dB measured insertion loss -54 dB measured cross-talk
JSH-33
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Switching Characteristics Transmitted Optical Power at 1550 nm [dB]
STANFORD
0 -20 -40 Output A Output B
-60
M1
M1 M2 B A
M4
M1
M2
M3
M4 M3
B
M4 M3
A
M1: 21.65V to 0V M1: 0V M3: 25.52V M3: 25.52Vto 0V
M1
M2 B A
M1: 0 V M3: 0Vto 25.52V
O-MEMS APS Short Course 3/11/01
M2 B A
M4 M3
M1: 0V to 22.24V M3: 25.52V JSH-34
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DMD Light Switches Mirror –10 deg Mirror +10 deg
Hinge
CMOS Substrate
Yoke Landing Tip
DMD Optical Switching Principle
1
SEM Photomicrographs of DMD Chips
(a)
(b)
(c)
(d)
Grating Light Modulator STANFORD
Beams up, reflection Individual ribbons are from 1 to 2 µm wide and Top electrode from 25 to 100 µm long. Silicon Nitride
Beams down, diffraction
Silicon Substrate Silicon Dioxide
Substrate electrode
Cross section O-MEMS APS Short Course 3/11/01
JSH-40
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2
Grating Light Valve Projector STANFORD
O-MEMS APS Short Course 3/11/01
JSH-41
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Micromachined Free-Space Micro-Optical Bench (FS-MOB) Active Laser Stripe
Semiconductor Edge-Emitting Laser Pre-aligned Micro-Fresnel Lens
3D Structures Pre-aligned to the Lens
Active Opto Devices
Micro-Actuators
Diffractive Optical Elements
Micromachined FS-MOB Refractive Optical Elements
M. C. Wu
Pre-Aligned and Monolithically Fabricated
Micro-Positioners
Integrated Photonic Laboratory
3
Out-of-Plane micro-Fresnel lens l
Low cost, batch processing technique to fabricate free-space micro-optical system.
l
All optical elements fabricated at the same time by photolithography.
→The optical system can be pre-aligned. l
Greatly reduce the size, weight, and volume of free-space micro-optical systems
Fabrication Processes :
PSG-2
Poly-1
Poly-2
PSG-1
Si or GaAs • Ref: Lin, Lee, Pister, and Wu, Electronics Letters, v.30, p.448, March 1994. M. C. Wu
Integrated Photonic Laboratory
Micro-Fresnel Lens with Integrated Scratch Drive Actuators (SDA) Micro-Fresnel Lens
Translation Stage
Scratch Drive Actuators (SDA)
Spring
M. C. Wu
Integrated Photonic Laboratory
4
Outline STANFORD
l
Overview l l
l
Mechanical O-MEMS l l l
l
Advantages Fundamentals Optical Communications Network Switches Optical Bench Displays l Torsional Mirror l Grating Light Valve
Semiconductor Optical Device O-MEMS Tunable Laser l Tunable Detector l Modeling l
l l
MEMS Systems Examples Summary
O-MEMS APS Short Course 3/11/01
JSH-45
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Need for Tunable Devices STANFORD
• Wavelength division multiplexing (WDM):
• •
•
• tunable vertical cavity lasers • tunable photodiodes • tunable phototransistors Optical Routing and Switching: • Beam steering Spectroscopy: • Gas sensing • Laser spectroscopy • Cavity ring-down spectroscopy • Intracavity laser absorption spectroscopy Adaptive Optics: • Tunable mirror arrays
O-MEMS APS Short Course 3/11/01
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Ar Ion Pumped Ti:Sapphire Tunable Laser STANFORD
O-MEMS APS Short Course 3/11/01
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Laser Background STANFORD
Mirror 1
Mirror 2
l
Laser: Gain + Feedback
L
Circ Wave
Inc
Gain Medium α(ω), g(ω)
(Mirrors)
Trans
Refl r1
Pump
r2
l
Oscillation/Lasing l
Gain > Loss (internal + mirror)
l
Resonance condition 2ωnL/c = 2πm or nL = mλ/2
O-MEMS APS Short Course 3/11/01
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Laser Background STANFORD
∆ωcavity
∆ωax
l
Resonance c m nL
I circ I inc l
Axial Mode Spacing axial
ω l
, where m = 1, 2, ...
c nL
Cavity Finesse F
g rt 1 g rt
axial cavity
O-MEMS APS Short Course 3/11/01
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Semiconductor Lasers: In-Plane vs. Vertical-Cavity STANFORD
In-Plane Edge-Emitting Laser
Vertical-Cavity Surface-Emitting Laser Top DBR
p AlGaAs cladding QW active region n AlGaAs cladding
GaAs substrate
GaAs substrate
p AlGaAs cladding + QW Active Region + n AlGaAs cladding Bottom DBR
l
Cavity length ~ 100-400 µm
l
Cavity length ( ) ~ 0.25 µm
l
High gain (2gL), low reflectance mirror is sufficient for lasing
l
Low gain (2gL), high reflectance mirror (> 99%) needed for lasing
l
Mirrors usually formed by cleaving ~ 30% reflectance
l
l
Small emission aperature produces highly astigmatic beam
Mirrors are made of 1/4 alternating low and high index materials such as: AlAs/GaAs
l
Circular beam
O-MEMS APS Short Course 3/11/01
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Why Vertical Cavity Devices? STANFORD
Short Cavity
Cavity Mode
∆λaxial ~ a few Å
λ
gain/transmission
gain/transmission
Long Cavity
Cavity Mode
∆λaxial ~ 100 nm
λ
• Axial mode spacing is inversely proportional to cavity length: ∆ωax = πc/nL
• Wide axial mode spacing in vertical cavities possibility for broad and continuous wavelength tuning (∆λ < ∆λaxial, ~100 nm or ~10%)
O-MEMS APS Short Course 3/11/01
JSH-51
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Wavelength Tuning in VCSELs STANFORD
R
I Mirror 1
r1
Ladj
Top Distributed Bragg Reflector QW active region λ Cavity Spacer
Pump
Circulating Wave Gain α(ω), g(ω)
Bottom DBR
GaAs substrate Conventional VCSEL nL = mλ/2
r2 T
Page ‹#›
Mirror 2
Tunable VCSEL nL + Ladj = mλ/2
O-MEMS APS Short Course 3/11/01
L Lcavity
JSH-52
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Hybrid Dielectric DBR Tunable VCSEL Structure STANFORD
Membrane Contact Pad
Spacer Layer Deformable Membrane Top Mirror
p-contact p-Contact Layer Quantum Well Active Region & Cavity Spacer
Air Gap
n-Distributed Bragg Reflector Anti-Reflective Coating
p-Contact Layer O-MEMS APS Short Course 3/11/01
JSH-53
53
Dielectric Mirror Deposition & Current Aperture Formation STANFORD
l
Grow epitaxial layers using MBE
l
Deposit backside anti-reflective coating & ohmic contact Deposit Si3N4 mechanical layer & Si3N4/SiO2 dielectric DBR Pattern/Etch to high Al content AlGaAs current confinement layer Wet Thermal oxidation of AlGaAs to form current aperture
l
l
l
O-MEMS APS Short Course 3/11/01
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Top Mirror Formation STANFORD
l
l
l
Pattern/Etch dielectric DBR to form central reflector region Evaporate/Liftoff Ti-Au adhesion layer
Evaporate/Liftoff Au mirror layer
O-MEMS APS Short Course 3/11/01
JSH-55
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Intracavity Contact STANFORD
l
l
Plasma etch mechanical nitride layer to form membrane Recess etch Al0.85Ga0.15 As sacrificial layer
l
Wet Etch sacrificial layer for intracavity contact
l
Evaporate/Liftoff Ti-Au intracavity contact
O-MEMS APS Short Course 3/11/01
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Membrane Release STANFORD
l
Pattern photoresist for membrane release
l
Wet Etch membrane release
l
Plasma removal of photoresist
O-MEMS APS Short Course 3/11/01
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SEM Images of Tunable Structure STANFORD
• 20-40 µm diameter membrane central reflector
• Shadow indicates the full releasing of the membrane. 4.3 m
• 85 X 5 µm membrane legs Oxidized current aperture
O-MEMS APS Short Course 3/11/01
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Semiconductor Coupled Cavity: 1.5 Pair Dielectric DBR STANFORD
Air Gap ~3/4 λ + δ GaAs 2λ Cavity Oxidized AlAs current aperture 2-60Å InGaAs QWs
Power (µW)
1500Å Au 1.5 pairs dielectric mirror λ/4 GaAs
22.5 Period GaAs/AlAs λ/4 DBR
5
5
4
4
3
3
2
2
1
1
0
Voltage (V)
Structure
0
0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 Current (mA)
l
SiO2/Si3N4/SiO2 stress-matched 1.5 pair dielectric DBR
l
99.91% calculated top mirror reflectivity
l
Typical device Ith ~ 0.35-0.7mA, Quantum efficiency ~ 6.5%
O-MEMS APS Short Course 3/11/01
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Semiconductor Coupled Cavity: 1.5 Pair Dielectric DBR STANFORD
0.5 RT 0.5mA CW
965
17.5V
0.3
Wavelength (nm)
Intensity (a.u.)
0.4
970
13.4V 9.4V 0 V 17.2V 15.4V 11.4V 5.4V 7.4V 16.4V
17.6V
17.7V
0.2 0.1
960
955 950
17.8V
0
9500
9550 9600 9650 Wavelength (Å)
9700
945
0
4
8 12 Voltage (V)
l
19.1 nm continuous tuning for 17.8 V membrane bias
l
24 dB mode suppression ratio
O-MEMS APS Short Course 3/11/01
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VCSEL Wavelength Tuning Transient Response STANFORD
Wavelength switching from 977.6 nm to 977.0 nm < 1 sec rise time, ~ 2 sec settling time
l l
2 0 -2
Voltage (V)
Signal (a.u.)
Tuning Voltage
-4 -6
977.6 nm
-8 -10 -12
977.0 nm
-14 -4
-2
0 2 Time (µsec)
O-MEMS APS Short Course 3/11/01
4
6 JSH-61
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Resonant Cavity Photodetection STANFORD
h
QW absorbing layers Circulating wave Bottom DBR (R2)
Quantum Efficiency ( )
Top DBR (R1)
p contact
1
0.8
R 1 = 0.8 R 2 = 0.99
R 1 = 0.4 0.6
0.4
R 1 = 0.8
0.2 R 2 = 0.9
n contact 0 0.01
l
0.1
1
10
Absorption ( d)
Quantum Efficiency max
R 1 = 0.2
(1+ R2 e − d ) − d = ) − d 2 (1− R1 )(1− e e ) (1− R R 1 2 (Kishino, 1991)
O-MEMS APS Short Course 3/11/01
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Tunable PIN Photodiode STANFORD
5 10 -6
• Reverse Bias The Tunable Laser (PIN diode) • Narrow Linewidth (below 4nm) • Tuning Range: 28.5 nm
Normalized Photoresponse (A.U.)
1.5 Volt 7.5 Volt 11.5 Volt
4 10 -6
16.5 Volt
3 10 -6
2 10 -6
1 10 -6
0 920
930
940
950
960
970
980
990
Wavelength (nm)
O-MEMS APS Short Course 3/11/01
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Mirror Curvature STANFORD
MUMPS Poly2
l
2-D Interferometry
l
Optical far-field measurements
Static deformation 1.2 µm
O-MEMS APS Short Course 3/11/01
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New AlOx/GaAs Top Membrane Structure STANFORD
GaAs/AlOx DBR Si3N4/Gold/Ti/GaAs Supporting Legs Silicon nitride Gold
n+ GaAs Substrate Tuning Contact
GaAs
DBR
Air Gap
• AlOx/GaAs: higher index contrast ratio, fewer DBR mirror pairs • Independent leg thickness enables stress and deflection optimization. O-MEMS APS Short Course 3/11/01
JSH-65
65
One-Dimensional Model of Movable Membrane STANFORD
• One-Dimensional Model: Four springs with Hook’s constant keff • •
attached to central reflector The balance of forces: Electrostatic force contributed from central plate and four legs is equal to the effective spring force Describe the system accurately without loss of physical meaning
O-MEMS APS Short Course 3/11/01
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Optical Properties of the cavity STANFORD
• Modeling of O-MEMS
• • •
devices is virtually nonexistant: serious design limitation Surface deformation scatters light out of the cavity Cavity loss increases linewidth Two top membrane designs compared using Fox & Li method
O-MEMS APS Short Course 3/11/01
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Optical Field Distribution STANFORD
• Fox & Li method used to
•
Normalized Field Pattern (A.U.)
•
simulate a plane wave bouncing between two mirrors. Examples • Tilted but flat surface • Symmetrically bent surface Result: • Tilted: the mode shifts • Symmetrical: the mode
1 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1
-10
-5
0
5
10
Radial Distance (mm)
intensity decreases in center, but increases at edges--leads to multi-mode lasing O-MEMS APS Short Course 3/11/01
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Outline STANFORD
l
Overview l l
l
Mechanical O-MEMS l l l
l
Advantages Fundamentals Optical Communications Network Switches Optical Bench Displays l Torsional Mirror l Grating Light Valve
Semiconductor Optical Device O-MEMS l l l
Tunable Laser Tunable Detector Modeling
MEMS Systems Examples l Summary l
O-MEMS APS Short Course 3/11/01
JSH-69
2D Scanning Microlens with Integrated Microactuators and Hybrid-Integrated VCSEL Integrated 3D Optics
“Raised” Microlens
Actuator Emitting Spot
VCSEL
Si Free-Space Micro-Optical Bench
M. C. Wu
Hybrid-Integrated Vertical Cavity Surface-Emitting Laser
Integrated Photonic Laboratory
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Integrated Michelson Interferometer Measure displacement and Movement direction of external Object with high resolution
Integrated Interferometer
Page ‹#›
Displacement Sensor Performance
System resolution < 20nm
Micro Bio-Assay System STANFORD
O-MEMS APS Short Course 3/11/01
JSH-74
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Micro Bio-Assay System STANFORD
Micro Fluidic Chamber
Micro Lens Array
O-MEMS APS Short Course 3/11/01
JSH-75
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Cavity Ring Down Spectroscopy STANFORD
Absorption spectroscopy for detection of low levels of species
Tunable Laser
Coupling Optics Sample
Detector
Ring-down Cavity Iout
B A
A B
λ
Time O-MEMS APS Short Course 3/11/01
JSH-76
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O-MEMS is an Enabling Technology for the New Millennium STANFORD
Communications: Fiber Switches. Femtosecond Lasers, Pulse Shaping, Modulators, Tunable Optical Devices l Optical Interconnects l Optical Data Storage l Displays: Projection, Head Mounted - Virtual Reality l
Repro-graphics: Printing, Scanners l Adaptive Optics l Optical Transducers and Sensors l Optical Spectroscopy and Instrumentation l
O-MEMS APS Short Course 3/11/01
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Where To Find Information? STANFORD
O-MEMS WWW Web Sites l
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http://snowmass.stanford.edu/ Tunable Filters, Photodetectors and Lasers: http://www.htc.honeywell.com/cap/sensors/sensors.html fiber-optic and sensors http://www.sandia.gov/LabNews/LN09-15-95/microengine.html Microengines http://www.janet.ucla.edu/dmsr.index.html Micromachined optical bench http://eto.sysplan.com/ETO/MEMS/Prog_Summaries/steering.html DARPA ETO Electromagnetic/Optical Beam Steering program http://www.ti.com/dlp/docs/papers/mems/0memsab.htm TI's Digital Mirror Devices http://www1.psi.ch/www_f3b_hn/home.html Interferometer http://dmtwww.epfl.ch/ims/www.html MEMS WWW sites around the world
O-MEMS APS Short Course 3/11/01
JSH-80
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