EPIC: The Convergence of Electronics & Photonics
Transcript of EPIC: The Convergence of Electronics & Photonics
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EPIC:The Convergence of Electronics & Photonics
K-Y Tu, Y.K. Chen, D.M. Gill, M. Rasras, S.S. Patel, A.E. WhiteBell Laboratories, Lucent Technologies
M. Grove, D.C. Carothers, A.T. Pomerene, T. ConwayBAE Systems
L.C. Kimerling, J. Michel, M.A. Beals, D.K. SparacinMassachusetts Institute of Technology
M. Lipson, A.B. ApselCornell University
C. WongColumbia University
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Spectrums of Signal to Process(example: commercial wireless)Spectrums of Signal to ProcessSpectrums of Signal to Process
(example: commercial wireless)(example: commercial wireless)
Land mobilesFixed wirelessAmateurRadiolocation
M: Mobile transmitB: Base station transmit
450 MHzGSM bands
419.8399.8389.8 429.8 457.6 467.6 486 496
MHz390.2380.2
BM
410.2 420.2 450.4 460.4 478.8 488.8
BM
BM
BM
890
900 MHzGSM bands 849792762 894
MHz777747
BM
824 869
BM
915 960935
BM
1900 MHzGSM/UMTS
bands 1930188017852110
MHz18051710
BM
1910 1990 21701850
BM
BM
1980
M
1920
B
20251900
GSM Bands
DCS 1800
PCS 1900
UMTS/FDD
UMTS/TDD
Broadcasting Satellites
380 500 740 960 1710 2170 MHz
470 1215 1980 2110
100 MHzBands (Needs more input!)
100 300
Groups of Spectrum
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7”x5.5”x1.3”
Typical Wireless Transceiver
5mmx5mmx1.2mm 2mmx3mmx0.5mm
Metallic cavity filter SAW or ceramic filters Active circuits
Best if Q >300Best if Q >300Would like Q’s >2,000Would like Q’s >2,000
Would likeQ’s >5,000
Would likeQ’s >5,000
Would likeQ’s >10,000
Would likeQ’s >10,000
Courtesy: Clark T.-C. Nguyen
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Processing Wireless Signals Optically
Antenna
Signal Analysis
Coax Cable
Signal Analysis
Antenna
Optical Fiber E to O O to E
SignalAnalysis
Antenna
Optical FiberE to O OSP* + O to E
*Optical Signal Processing,for e.g., separating signal into individual channels
•• GovernmentGovernmentAppsApps– Performance
critical• Optics compact!
•• CommercialCommercialAppsApps– Cost critical
• Opticsexpensive!
Need toNeed toreduce cost ofreduce cost of
opticalopticalcomponentscomponents
Reduce weight, size & powerReduce weight, size & power
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Cost Reduction by Integration
• Electronics in “standard siliconstandard silicon”– PCs, PDAs, cars, cell phones, GameBoys, DVRs,
…
–– standard silicon has highest volume, ensuresstandard silicon has highest volume, ensureslowest costlowest cost
•• No equivalent of No equivalent of ““standard siliconstandard silicon”” in inopticsoptics– Optical devices built on diverse technology
platforms• InP, LiNbO3, InGaAs, SiO2-PLCs, MEMS, LC, …
To reduceTo reducecost of opticalcost of opticalcomponentscomponents
IntegrateIntegrateoptics onoptics onstandardstandardsiliconsilicon
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Program Objectives Approach
Tasks
To demonstrate the world’s first denselyintegrated “Application Specific ElectronicPhotonic Integrated Circuit” (AS-EPIC)using an electronic warfare (EW)application as a demonstration vehicle.
Integrate the best technology and designsfrom BAE Systems, Lucent Technologies,MIT, and AWR to realize our AS-EPIC chip.This involves combining CMOScompatible, low loss, high index contrast(HIC) waveguides and electro opticcomponents to form optical filters,modulators, and detectors.
• Develop an integrated, broadband(2MHz-18GHz), RF-photonic channelizer.• Create an open-architecture opticalcomponent library that is completelycompatible with CMOS processes .• Fab devices at BAE Foundry andcharacterize at team test facilities
EW AS-EPIC
EPIC RF PhotonicChannelizer “Chip”
4.5X Increase IBW95X Reduction Size
80X Reduction in Weight5X Reduction in *Power*≥100X Reduction in Cost
EW Microwave Channelizer
7”
“Nickel” Size
EPIC RF PhotonicChannelizer “Chip”
Increased IBWReduction in Size
Reduction in Weight Reduction in Power Reduction in Cost
EW Microwave Channelizer
7”
“Nickel” Size
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Why Now?
1
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1000
10000
1980 1990 2000 2010 2020
QUANTUM REGIMEQUANTUM REGIME
FE
AT
UR
E S
IZE
(n
m)
FE
AT
UR
E S
I ZE
(n
m)
YearYear
Electron Electron λ λ (~ 10 nm)(~ 10 nm)
Photon Photon λ λ (~ 350 - 400 nm)(~ 350 - 400 nm)
20042004
90 nm90 nm
Moore’s Law
• Technological advances in standard silicon processingmakes this the right time!
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Optics Integration with SiliconOptics Integration with SiliconElectronicsElectronics
• Use same standard silicon processes to buildoptical and electronic functionality
Electronic & Photonic Integrated CircuitsElectronic & Photonic Integrated Circuits
ELECTRONICSELECTRONICS ininstandard siliconstandard silicon
OPTICS inOPTICS instandard siliconstandard silicon
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EPIC Channelizer ChipOptical Channellizer
Modulator
Filter 1
Filter n
Detector
Detector
Mul
ti-m
ode
Inte
rfer
omet
ricS
plitt
er
TIA
TIA
RF IN
LASER
• 20 X 20 mm Chip• 100 Photonic Devices• 1000 Electrical Devices• Modulator• Multimode Interferometric Splitter• Filter Bank• Detector• TIA• Optical Filter Elements• Optical Bends & Transitions
AS-EPICBlock Diagram
Modulator
One Element ofA Filter Bank
Detector/TIA
Mode-lockedLaser
300MHz to 2.2GHz RF
Detected Waveforms(Electrical)
Multimode InterferometricSplitter
OpticalChannelizer
Slice
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Optical Waveguides
SOI waveguides achieved 0.35 dB/cm transmission loss
Phase I Goal: <0.5 dB/cm achieved
Transmission Loss = 0.35 dB/cm
Phase I Goal: <0.5 dB/cm achieved
Transmission Loss = 0.35 dB/cm
Latest waveguide short loop demonstrated State of the Art transmission loss for “highly
confined” deposited waveguides (~4 dB/cm)
Standard test structure for waveguide loss
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Courtesy of Armani, Spillane, Kippenberg, Vahala
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Filter Layout
Phase shifter
• Can dynamically move the zeros & poles of the 4thorder filter providing wide range of passband tunability
Fully tunable 4th order pole-zero filter
In Κ=0.5R1 R2
R3 R4
Κ=0.5
In
β-φtot
φtot-β
κ1, φ1
Cross
Tunable MZcoupler κ2, φ2
κ1, φ∗1 κ2, φ∗2
Through
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Flexible Channel Tuning
Single designcan work for all
channels!
-40
-30
-20
-10
0
Tra
nsm
ittan
ce (
dB)
193.420193.416193.412193.408
Frequency (THz)
f0 f0+2.5 GHzf0-2.5 GHz
Modulator
Filter 1
Filter n
Detector
Detector
Mul
ti-m
ode
Inte
rfer
omet
ricS
plitt
er
TIA
TIA
CWLASER
SiliconChip
RF Out
RF Out
RF In
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Ge-on-Si PhotodetectorIntegration
102 103 1040
10
20
30
40
50
60
70
80
(Ban
dw
idth
) x
(Qu
antu
m e
ffic
ien
cy)
(GH
z)
Detector Size (µm2)
d=0.5um d=1.0um d=1.5um d=2.0um
Size : 5µm×20µmQ.E: 90%
Waveguide-Integrated,
EPIC Photodetector
Discrete, free-spacePhotodetectors
RC time limittransit timelimit
Waveguide -Detector Coupling
Efficiency
Speed (Gb/s)
Size (um)
Responsivity (A/W)
Wavelength BW(nm)
Ge Photodetector
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Micro-ring Modulator
1.5 Gbit/s using RZ pattern
• Lowest power consumptionreported to date. - Less than 0.3V and µA currentneeded for complete modulation inDC. - In AC, 3.3Vpp and 1mA currentwere used.• Expected theoretical bandwidthlimit >10Gb/s!
Diameter = 12_m
Width = 450nm
Gap = 200nm
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RF Performance of Channelizer
Better preamp, higher LO, lower optical loss willBetter preamp, higher LO, lower optical loss willfurther improve system NF and SFDRfurther improve system NF and SFDR
NF = 68dB IIP3 = 26dBm
SFDR = 88 dB*Hz2/3
Photonic LO f0+ 2.5GHz
Up-converted signal Tuned to f0+3.1GHz center
f0
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AS-EPICSummary
Devices• Optical filter: design, fabrication and test
– the most sophisticated tunable optical filter with CMOSprocessing
– the first optically-lossless CMOS thermo-optic switching(TOS)
• Si waveguide: design, fabrication and test– SOI (0.35dB/cm) and deposited silicon ( 4dB/cm)
• Ge detector: design, fabrication and test– BW=2.5GHz@1500nm, R>0.8A/W
• Si Modulator: design, fabrication and test– B=6 Gbit/sec, ER=15 dB, L=10 µm, 3mW
System• SFDR: measured 88 dB*Hz 2/3 in surrogate system• Channel Rejection: measured >28.6 dB rejection ratio