epic: the convergence of electronics & photonics

communications technology roadmaphttp://mph-roadmap.mit.edu

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


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


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




Courtesy: Clark T.-C. Nguyen


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


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


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


Why Now?

1

10

100

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!


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


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


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


Courtesy of Armani, Spillane, Kippenberg, Vahala


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


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


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


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


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


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

epic: the convergence of electronics & photonics

Documents