High-Speed Opto-Electronic Components for Digital and Analog RF Systems

K. Y. LiouDirectorLaser Technology & Government BusinessMultiplex, Inc.kyliou@multiplexinc.com

WOCC April 23, 2005

5000 Hadley Road

South Plainfield, NJ 07080 USA

www.multiplexinc.com

Active Opto-Electronic Component Solutions for Optical Networks

Custom Design Systems

1550 Transponder

1310 Transponder

Tunable EML

980 Pump Laser (EDFA)

APD Receiver

PIN Receiver

1550 EML (10 Gb/s)

1310 EML (10 Gb/s)

1550 EML (2.5 Gb/s)

Access(2-10km)

Metro(20-40 km)

Regional(60-80 km)

Long-Haul80+ km)

* 2.5Gb/s application extends to >640 km

Electro-absorption Modulated Laser (EML)

-32 -31 -30 -29 -28 -27 -26 -25 -24 -23 -22<P> (dBm)

BER

0 km

50km

85km

1E-4

1E-5

1E-6

1E-7

1E-8

1E-91E-10

1E-121E-11

1E-13

1E-151E-14

-32 -31 -30 -29 -28 -27 -26 -25 -24 -23 -22-32 -31 -30 -29 -28 -27 -26 -25 -24 -23 -22<P> (dBm)

BER

0 km

50km

85km

0 km

50km

85km

1E-4

1E-5

1E-6

1E-7

1E-8

1E-91E-10

1E-121E-11

1E-13

1E-151E-14

1E-4

1E-5

1E-6

1E-7

1E-8

1E-91E-10

1E-121E-11

1E-13

1E-151E-14

DFB LaserSection

EA ModulatorSection

n-InP Substrate

InGaAsPGrating

Fe:InPBlocking

p-InGaAs/InP Cap

Selective-AreaMOCVD Grown MQW-SCH

HR

AR

• MQW DFB laser and EA modulator• Low cost integration by SAG (selective area growth)• Fiber packaging same as DFB laser• 80-km DWDM transmission• Replaces hybrid-packaged Laser-LiNbO3 modulators

even for long-haul DWDM

10 Gb/s

Wavelength Tunable EML

10-10

10-9

10-8

10-7

10-6

1.5561.5541.5521.5501.5481.5461.5441.542

1542 1556Wavelength (nm.)

From MOCVD Wafer Growth to Subsystems and Fiber Transmission Test

Selective Area MOVPE Growth

(1) Indium rich (compressive strain) MQW inside slot(2) Thicker MQW layers inside the slot (Red shifted)

• Vapor phase diffusion• Surface migration

Z

SiO2mask

E g> 40-50 meV(∆λ≈100 nm)

Laser ModulatorInP

40-60 µm

Increased concentrationGroup III Precursors

Enhanced

Micro Photo Luminescent Measurement

Group-III Precursors• Vapor-phase diffusion• Surface migration

Cross-Sectional View During Growth

DFB MOD.

z

z

Eg40 – 50 meV

Top View

SiO2mask

80

60

40

20

0

Wav

eleg

nth

Offs

et (n

m)

20151050SAG Oxide Width (µm)

Quantum Well Number: 9 Wells 7 Wells 3 Wells

• Calibration of SAG-MOCVD growth• Bandgap λ shift by well thickness (and alloy composition,

strain)• SAG mask design for active (source, modulator, detector)

and passive waveguide integration

Cross-sectional Transmission Electron Microscopy of MQW and DFB Grating Structure

Grating

MQW layers

56.5nm

158.7nm

213.1nm

36.9nm

52.2nm

132.6nm

10 Gb/s 85km EML Module

Laser operating current 100mA, modulated power 3.67dBm

Filtered eye diagram of 85km EML module

BER Fiber Transmission TestMTX510EW SN: FZ0091 Date: 3/17/2004

Vc2 = -3.70V Cross % = 47% laser current = 100mA Pmod = 3.67dBm

-32 -31 -30 -29 -28 -27 -26 -25 -24 -23 -22

<P> (dBm)

BER

0 km

50km

85km

1E-4

1E-5

1E-6

1E-7

1E-8

1E-9

1E-10

1E-121E-11

1E-13

1E-151E-14

Tunable EML (DBR laser+EA modulator)

-25 -24 -23 -22 -21 -20 -19 -18 -17 -16 -15

<P> (dBm)

BER

.

Ch_0; Back to BackCh_4; Back to BackCh_9; Back to BackCh_0; After 50kmCh_4; After 50kmCh_9; After 50km

1E-4

1E-5

1E-6

1E-7

1E-8

1E-9

1E-10

1E-12

1E-11

1E-13

1E-14

PRBS=231-1 @ 10Gb/s

Rel

ativ

e Po

wer

(dB)

Wavelength (µm)

10-10

10-9

10-8

10-7

10-6

1.5561.5541.5521.5501.5481.5461.5441.542

-10

-20

-30

-40

0

Rel

ativ

e Po

wer

(dB)

Wavelength (µm)

10-10

10-9

10-8

10-7

10-6

1.5561.5541.5521.5501.5481.5461.5441.542

-10

-20

-30

-40

0

10-10

10-9

10-8

10-7

10-6

1.5561.5541.5521.5501.5481.5461.5441.542

10-10

10-9

10-8

10-7

10-6

1.5561.5541.5521.5501.5481.5461.5441.542

-10

-20

-30

-40

0

• Wavelength tuning characteristics (12 nm range)

• Fiber transmission test at 50-GHz spaced ITU channels

10 Gb/s TEML

2.5 Gb/s 640km EML Module

Laser operating current 60mA, modulated power 0.07dBm

Integrated wavelength locker for DWDM

Filtered eye diagram of 640km 2.5 Gb/s EML module

The Multiplex Family of EMLs

Gen-1 EML Gen-2 EML Gen-3 EML

7-pin with GPO 14-pin butterfly package 21-pin package

Industry-standard configuration

30GHz through pin replaces GPO

50GHz RF feed-through pins

Qualified to Telcordia GR-468-CORE

EML driver IC inside package

G-S-G coplanar 50 Ohms ports

Qualified to Telcordia GR-468-CORE

Integrated driver IC and wavelength locker

EMLsHigh-Speed

• 2.5G EML w/WLL - Current Product

• 10G GPO EML w/WLL - March/2005

• 10G Tunable EML w/WLL (5nm Tuning Range) - Current Product

• 10G Tunable EML w/WLL (12nm Tuning Range) - Q3/2005

• Miniature 10G Tunable EML w/WLL - Q3/2005

Next Generation EML Products

Introducing: Injection Locked Laser Transmitter

R&D Team: Multiplex Inc, UC Berkeley, UCSDSponsored by: DARPA RFLICS

Directly Modulated Analog Fiber Optic Links

LaserOutputAnalogSignal

InputAnalogSignal

Direct Modulated Link

Issues of Direct Mod Laser– Low RF efficiency– Limited bandwidth– Nonlinear distortions

Issues of Direct Mod Laser– Low RF efficiency– Limited bandwidth– Nonlinear distortions

Mod

ulat

ion

Res

pons

e

Modulation Frequency

Increase Efficiency

Increase Bandwidth

Monolithic Injection Locking Using Two Section DFB Laser

OpticalCirculator

PolarizationController

IDC+IRF

Slave LaserOutput

IDC

Master Laser

Conventional Optical Injection Locking: Bench Top

• Single laser package• No optical isolator / circulator• Automatic polarization match

and optical alignment• Current tuning• Environmentally robust

SlaveDFB

MasterDFB

SlaveDFB

MasterDFB

New Monolithic Optical Injection Scheme Invented in RFLICS Program

Injection-locking by Two-section DFB LaserLocking Regime of Externally Injection-locked Laser

-40 -30 -20 -10 0-25

-20

-15

-10

-5

0

5

10

S tab leLocking

U nstab leLocking

U nlocking

U nlocking

in j / Poutfr ) [dB ](= PIn jection R atio

∆f (

=f M

Lf S

L)

[ GH

z ]

-

Linewidth Enhancement Factor α

Asymmetric Stable Locking Range

Negative Detuning in Monolithic Injection-locked Laser

MasterMasterSectionSection

Slave Slave SectionSection

Frequency∆f

Frequency

Injection Locked

No isolator between Master & Slave Section

Monolithic Injection Locking UsingTwo Section DFB Laser

• Single laser package• No optical isolator / circulator• Automatic polarization match and

optical alignment• Current tuning• Environmentally robust

New Monolithic Optical Injection Scheme Invented in RFLICS Program

SlaveDFB

MasterDFB

Fully packaged module with output fiber, optical isolator, master laser power monitor, TEC, RF input port

Integrated master-slave laser on submount with 25Ω termination for direct modulation

Monolithic Injection-locked laser in 25-GHz fiber-packaged module

20 GHz Modulation Applied to Slave Laser

Modulation Response

0 5 10 15 20 25-50

-40

-30

-20

-10

0

10

20

30free-running (ML 0 mA) Injection-locked (ML 10 mA)Injection-locked (ML 15 mA)Injection-locked (ML 18.6 mA)

Res

pons

e (d

B)

Frequency (GHz)

SL 73.8 mA

Red – injection locked

Blue – unlocked

0 5 10 15 20 25 30 35 40 45 50 55 60 65-50

-40

-30

-20

-10

2nd

Harm

onic

Dis

tort

ion

(dB

c)

ML Current (mA)

Locking Range

Modulation Freq. = 9 GHz

20 dB

0 5 10 15 20 25 30 35 40 45 50 55 60 65-50

-40

-30

-20

-10

2nd

Harm

onic

Dis

tort

ion

(dB

c)

ML Current (mA)

Locking Range

Modulation Freq. = 9 GHz

20 dB

Monolithic Injection Locked DFB Laser

• Improved RF modulation linearity• Suppression of harmonic distortion• Increased spurious-free dynamic range• Enhanced modulation bandwidth

Enhanced performance without increasing cost by InP-InGaAsP chip integration

The Multiplex Family of Receivers

Gen-2 Receiver Gen-3 ReceiverGen-1 Receiver

PIN PIN and APD versions PIN and APD versions

Ultra-compact surface-mount MSA package

Single Output Co-planar differential outputs

First with integrated limiting amplifier Unique “Gull-Wing” Pins

(> 20GHz BW)Small-form package

APD (Avalanche Photodiode) Design

Bonding pad

Insulator

InP

Multiplication Region

Q-layer

InGaAs absorber

InP

N-contact

Center junction

Guard ring

Charge Layer

AR coating Incident light

Avalanche Multiplication

Electric Field

Hole

Electron

M= 8

Electron Current

Hole Current

Incident Light

APD BER Measurement

BER MeasurementRP192DL-R2100073

λ=1.55µm; PRBS=231-1 @ 10Gb/s

-35 -34 -33 -32 -31 -30 -29 -28 -27 -26 -25

<P> (dBm)

BER

25 Deg. C;V_APD=24.14V

75 Deg. C;V_APD=26.60V

-10 Deg. C;V_APD=21.84V

1E-4

1E-5

1E-6

1E-7

1E-8

1E-9

1E-10

1E-12

1E-11

1E-131E-141E-15

RECEIVERSHigh-Sensitivity

Next Generation10Gb Receiver Products

• Ultra High Sensitivity APD Receiver: 2-3 dB better sensitivity than the current APD receiver.Sample: Q3/2005; Production Q4/2005

( Ultra Low Noise Lens APD)

• Dispersion Compensation Receivers: Optical dispersion compensation + Ultra High Sensitivity APD Receiver

Demonstration: Q2/2006

The Multiplex Family of Transponders

Gen-1 Transponder Gen-2 Transponder Gen-3 Transponder

200-pin MSA 300-pin MSA 300-pin MSA Flat-Top

Ability to mount customer-designed external heat sink

MSA small-form-factor: 2” x 3” x 0.5”

MSA small-form-factor: 2.2” x 3” x 0.56”

DWDM ITU wavelength locked (stabilized)1310 or 1550nm EML PIN and APD versions

Tunable over 16 channels

PIN and APD versions

SR-1, SR-2, IR-1, IR-2 and LR-2

The Power of Vertical Integration

2km TXPR (1310)1310 EML

1550 EML

TEML

PIN

APD

40km TXPR (1550)Tunable TXPR (1550)

80km TXPR (1550)40km TXPR (1310, dispersion free)

80km Tunable TXPR (1550)

Core Technology Building BlocksProducts:Expertise:Technology:

APD PIN EML TEML PUMP

Packaging and AssemblyRF Design Optical Design IC Design

INTEGRATIONVe

rtic

al In

tegr

atio

n

MOCVD growth & Processing

Modules

Custom-Design Systems

Subsystems

Expanding

Chips

Foundry ServicesEPI-Wafer Growth & Chip Processing

Custom SystemsTranspondersTunable EMLsPump Combiner

EMLsReceiversPump

Chips

Multiplex FacilitiesCorporate Headquarters

& Front-End Manufacturing

- MOCVD wafer growth

- Chip fabrication

- Administration

Back-End Manufacturing

- Module packaging

- Subsystem Assembly

High-Speed Design Center

Facilities are located in South Plainfield, New Jersey

Multiplex Proprietary Information

北京市朝阳区建国路88号现代城4号楼3001室

3001 Bldg.4, Xian Dai City 88 Jian Guo Road, Chao Yang DistrictBeijing, 100022 ChinaTel: 011-86-10-85800526

Multiplex, Inc. Beijing Office