Semiconductor Lasers for High Bit Rate
Optical Communication Networks
R. Paoletti, R&D managerR. Paoletti, R&D manager
TTCTTC-- Avago Technologies Italy, Via Schiaparelli 12, 10148 Torino, ITAvago Technologies Italy, Via Schiaparelli 12, 10148 Torino, ITALYALY
PaviaPavia, 22/06/2009, 22/06/2009
Roberto Paoletti, Pavia
22 June, 2009
Page 2
Semiconductor Lasers for High Bit Rate
Optical Communication Networks
Abstract
• Internet and intranet data traffic constantly increased during last years, and the consequent band demand is pushing research and development of high speed optical modules operating at 17 Gb/s (Fiber Channel applications, FC) and 40 / 100Gb/s (Gigabit Ethernet, GbE). Main requirements of such a transmitters are high performances, reliability, power consumption and manufacturability. Talk will reports semiconductor laser sources suitable for such demanding applications, underlying the key technologies, and benchmarking the results proposed by the world’s most important research centers.
Roberto Paoletti (M’97) Roberto Paoletti was born in Vado Ligure (Savona), Italy, in 1966. He received the
laurea degree in Electronic Engineer from the University of Genova in 1991, and the Ph. D. degree in
Electronic at the Electronic Department of Politecnico of Turin, Italy, in 1995, studying high frequency
characterization, modeling and equivalent circuits of high speed semiconductor lasers and packages.
In 1995 he joined the former CSELT, Torino, Italy, then TTC Agilent technologies and now Avago
technologies, Italy. In the last years he has been responsible of research projects on new laser devices, and
mainly involved in design, characterization and reliability of high speed optoelectronic devices. He is author
and co-author of more than 50 papers, 5 patents and a book on high frequency modeling and characterization of semiconductor laser sources, as well as reviewer for technical journals.
Mr. Paoletti is a member of the IEEE Lasers and Electro-Optics Society.
Roberto Paoletti, Pavia
22 June, 2009
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Outline
• Avago: company overview
• Laser sources for ““pluggable transceiver pluggable transceiver worldworld””
Roberto Paoletti, Pavia
22 June, 2009
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1939
Hewlett Packard
Foundation (T&M)
• Test & Measurement
• Life science
• Semiconductor components
• Computers/imaging…
November 1, 1999
Agilent spin-off
~80000 employees
Computers, printers, imaging, …
~40000 employees
T&M, Life science,
semiconductor components
December 1, 2005
Avago spin off
~ 6500 employees
Semiconductor
components
T&M, Life science
Acquisition of TTC
former optoelectronic technology division of CSELT
R&D Corporate Center of STET (now Telecom)
Avago History
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22 June, 2009
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Product leadership in target markets
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22 June, 2009
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� 40-years heritage of innovation and technology leadership
� Over 2,000 patent and patent applications
� Over 1,000 design engineers
Leading in Technology Innovation
Fiber Optic Products Division
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22 June, 2009
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Technical Edge: Innovation History and ExpertiseStrategic Partner of Choice World’s 1st production transceiver
1st to market with VCSEL transceivers
1st OC-48 part (2x9 SC Duplex)
1st 10G XENPAK
Agilent is spun off from HP
1st 12x2.5G parallel optic transceiver
1st to market with 10G SFP+
1st to market with 8G SFPs
Avago is spun off from Agilent
1st to market with 12x6G parallel optic
1st to demonstrate full 17G SFP1st to demonstrate full 100G parallel optics
1999
2001
2002
2005
2007
2008
1998
1996
1978
• Module design
• 30 years of first’s and standards leadership
• Leading green technologies – lowest power / extended temperature SFP+ designs
• IC development
• Enable next generation optics, time to market
• Lower cost, best power roadmaps, features
• Only POD supplier with DMI, pre-emphasis, etc.
• Packaging and sub-assembly
• Proven mastery of bulk optic technology
• Capability for highly dense optical footprints
Flex Optics Bulk Optics
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22 June, 2009
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Outline
• Avago: company overview
• Laser sources for ““pluggable transceiver pluggable transceiver worldworld””
Roberto Paoletti, Pavia
22 June, 2009
Page 10
Outline
• Introduction
- Datacom – telecom networks history
- Pluggable solutions
• 10 Gb devices and technologies for pluggable transceivers
- Laser basic concepts
- Key design elements for high performances laser sources
- Advanced laser sources for pluggable transceivers
- TTC III-V technology overview
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22 June, 2009
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FIBER OPTIC History:
1960: First proposal of fiber optic for telecom.Basic design [Kao STC]
1970: Production of first fiber optic [Corning]
1977: First fiber optic network (1.5 miles)in Chicago [ATT Bell Labs]
1988: First transoceanic fiber-optic cable (3148 miles,40000 simultaeous telephone calls)
Dr. Kao
1960
LASER History:
1960: First Laser (Ruby) [Hughes Labs]
1962: First Semiconductor Laser (GaAs @T = - 200 oC) [GEC, IBM, MIT]
1970: First Semiconductor Laser at room temp. [Bell Labs, Ioffe Phys.Tech Inst. USSR]
1972: Invention of DFB Laser [Bell Labs]
1984: First Strained MQW in semiconductor laser
1990- Lasers for optical telecom
2000- Uncooled telecom lasers
GEC 1962
(Optical) Telecom History
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22 June, 2009
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DATACOM TELECOM
DFBFP
VCSEL EML
10 Gb/s LASER Sources
Long Haul
Metro
Storage
2-20 km 20-100 km
Enterprise
Today Optical Network
10km 100km100m10m 1km
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~250 x 250 mm
LASER
XFP(78 x 18mm)
X2XENPAK(100 x 50mm)
Evolution (since 2000)
PLUGGABILITY: PAY AS YOU GOPLUGGABILITY: PAY AS YOU GO
• Strong limits in space available and power budget
• Wide temperature operation (0÷85oC)
⇒⇒⇒⇒ Requirement on lasers:
• High temperature operation (preferably uncooled)
• Low cost, high manufacturing yield, high reliability
• no compromise on High performance
(high bit rate, high optical power, high spectral purity, …)
• Monolithic integration can provide:
• Small and smart devices (High functionality)
Pluggability: a keyword…From transceiver cards to hot-pluggable transceiver modules
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22 June, 2009
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Optical coupling:
Lens+Optical Isolator +
pigtailed fiber
Chip
laser
From a Butterfly Laser Module….The 1990 Technology
Temperature
control
Back detectorElectrical / RF
connections
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Avago Fiber Optics Portfolio
Enterprise SONETStorage Base StationParallel
10G leadership• 1st to market SFP+• 1st to market LRM• Superior VCSELs• Only extended temp range part• Lower power
High reliability, low cost 1G SFP
Proven supply assurance
Broad portfolio• OC-3 to 192 in multiple form factors and distances• Industrial tempavailable (includingXFP-LR/SR1)• Superior EMIperformance
#2 in market• 8G leadership• Industry’s most reliable 4G VCSEL• Industry’s best defect PPM rate• 1st 17G SFP demo• Only extended temp range 8G part
Strategic partner to key industry players
Innovative low cost design
Enabling time-to-mkt• 1st 100G POD demo• 1st 12x6G POD• World’s strategic parallel optics partner
Superior feature set –DMI, pre-emphasis
Unsurpassed delivery record
Proven quality
Market leader• 1st and only OBSAI/CPRI specific portfolio• High BER and industrial temp rates
Critical partner to leading players• Nextgen partner• Proven reliability
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22 June, 2009
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Outline
• Introduction
- Datacom – telecom networks history
- Pluggable solutions
• 10 Gb devices and technologies for pluggabletransceivers
- Laser basic concepts
- Key design elements for high performances laser sources
- Advanced laser sources for pluggable transceivers
- TTC III-V technology overview
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22 June, 2009
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MQW Active layer
• Active material: MQW Multi Quantum Well structure �
dimensional control at nanometric scale
• Wavelength selection: grating structure � dimensional control
at sub-µm scale
• Lateral confinement: ridge structure � dimensional control at
µm range
QUANTUM WELL
BARRIER
X 300.000 Grating
Confinement
Structure
Lasers for pluggable modules: key device elements for outstanding performances
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Fabry-Perot Laser
1280 1285 1290 1295 1300 1305
-70
-60
-50
-40
-30
-20
Wavelength (nm)
Amplitude (dBm)
Device:br00T20u; I = 30.0 mA; Peak: 1291.0 nm; 23-Jan-2003
Optical cavity = active material
Ibias
Multimodal emission
Short haul – not necessarily true…
L Nn
====λλλλ
2
N= integer
n=refractive index
λλλλ = wavelength
λλλλ
Cavity modes
0 50 1000
5
10
15
20Optical Power (T=20, 40, 60, 80, 85 °C)
Current (mA); - 24-Nov-2008
Power (m
W)
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Grating
•Phase shifted grating allows to get
100% single mode yield, for ideal
AR/AR coatings on both facets
θ 90+θb
b+Λ = m (λ / n)
b = Λ sinθΛ (1+sinθ)=m(λ / n)
Λ =m(λ / 2n)Λ =m(λ / 2n)Bragg wavelength
DFB Laser
1280 1300 1320 1340 1360-70
-60
-50
-40
-30
-20
-10
0
10
Wavelength (nm)
Rel. Amplitude (dB)
λ Peak: 1316.9 nm; SMSR: 53 dB
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Ridge structure
•No lateral blocking layers
•Very simple technological
process (one-step epi-growth)
•Suitable for Al-based lasers
and low cost devices
Optimised facet cleavage processOptimised facet cleavage process
Heat pathHeat path
Narrow reverse mesa (small cavity, fast chips)Narrow reverse mesa (small cavity, fast chips)
TiTi--PtPt--Au metalAu metal
SiOSiO22
Au plated padAu plated pad
To get performances: design (ridge )
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To get performances: control (MQW)
QWs Period 150
152
154
156
158
160
162
164
FA048
FA041
FA056
FA038
FA044
FA052
DA035
DA038
DA034
DA032*
DA040
DA044
DA101U
DA115*
DA071*
DA126
DA129
DA133
DA107L
DA117
FA095*
DA158L
DA171
DA199-203
DA215-219
DA229
FA128-132
FA117-121
FA122-126
DA259-261
DA269-273
DA279-284
DA297-302
DA315-320
DA333-338
Process name
PERIOD [Å]
MANIFOLD
MAN
IFOLD
MAN
IFOLD
R & D
ON-LINE DATA POINTS ON-LINE - 2 MRbar/1.128 line USL
ON-LINE LCL ON-LINE - 1 MRbar/1.128 line TARGET
ON-LINE CL ON-LINE + 1 MRbar/1.128 line LSL
ON-LINE UCL ON-LINE +2 MRbar/1.128 line ON-LINE OUTLIERS
All production wafers are inspected before wafer fabprocessing MQW period control within 0.3 nm (3σσσσ)
MQW period control chart
Out of control:Out of control:
NO Performances; NO reliabilityNO Performances; NO reliability
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0 10 20 30 40 50 60 70 80 90 1000
5
10
15
20
25
30
35
40
45
Current (mA); - 09-Aug-2002
Power (m
W) T=20-100 ºC
InGaAsP-based
MQW
InGaAsP-based
MQW
MQW active material optimization
0 10 20 30 40 50 60 70 80 90 1000
5
10
15
20
25
30
35
40
0 10 20 30 40 50 60 70 80 90 1000
Current (mA); - 20-Aug 2004
5
10
15
20
25
30
35
40
Power (m
W)
T=20-100 ºC
InGaAsAl-based
MQW
InGaAsAl-based
MQW
T0=95 KT0=48 K
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Optical coupling:
Lens+Optical Isolator +
pigtailed fiber
Chip
laser
Direct Modulation of Laser ModuleButterfly Laser Module
Temperature
control
Back detectorElectrical / RF
connections
RF
Roberto Paoletti, Pavia
Intensity modulation of laser sources
• Laser chip equivalent circuit
0 5 10 15 20-25
-20
-15
-10
-5
0
5
10
Frequency (GHz)
Rel. Amplitude (dB)
Ith+ 10 mA: (I
th= 6 mA); f
-3dB= 7.93 GHz
Ith+ 30 mA: (I
th= 6 mA); f
-3dB= 13.29 GHz
Ith+ 50 mA: (I
th= 6 mA); f
-3dB= 16.47 GHz
Ith+ 70 mA: (I
th= 6 mA); f
-3dB= 18.56 GHz
Ith+ 90 mA: (I
th= 6 mA); f
-3dB= 19.95 GHz
Increasing I-Ith
thr IIf −∝
thr IIf −∝Parasitics
Active material
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Intensity modulation of laser sources:
chip parasitics
Geometrical analysis
Equivalent circuit
Simulation and experimental results
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22 June, 2009
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Outline
• Introduction
- Datacom – telecom networks history
- Pluggable solutions
• 10 Gb devices and technologies for pluggabletransceivers
- Laser basic concepts
- Key design elements for high performances laser sources
- Advanced laser sources for pluggable transceivers
- TTC III-V technology overview
Roberto Paoletti, Pavia
22 June, 2009
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Agilent uncooled InGaAlAs ridge FP laser
for 10GBASE-LRM product (300 m MMF)
Device design:•Active layer: Al based materialDesigned to enhance T0
• 9 InGaAlAs 55Å wells; strain +0.8%
• 8 InGaAlAs100Å barriers; strain –0.4%
• 2xSCH1: InGaAlAs 350Å• 2xSCH2: InAlAs 500Å
• Device technology:High yield/low cost/Al compatible
• Reversed mesa ridge• Auto-aligned mesa
•Optical cavity:Very fast chip at high T operation
• Narrow cavity volume • Hr coating optimised versus
both Temperature and speed
200 µµµµm long x 250 µµµµm wide device
Avago/TTC Post
Deadline Paper at
OFC 2005
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Device results - static
20 °C base chip temperature:• Threshold 7.6 mA•High power 23 mW
85 °C base chip temperature:• threshold 15.6 mA • power 16.8 mW
95 °C base chip temperature:• threshold as low as 18 mA• Still more than 15 mW
0 10 20 30 40 50 60 70 80 90 1000
5
10
15
20
25
fa021ak113: Optical Power (T=20, 40, 60, 80, 85, 90, 95 °C)
Current (mA); - 23-Dec-2004
Power (m
W)
T=20ºC; Ith= 7.6mA; PIth+30
= 8.9mW; Pmax
= 23.8mW
T=40ºC; Ith= 9.3mA; PIth+30
= 8.5mW, Pratio,Ith+30
=0.95; Pmax
= 22.4mW
T=60ºC; Ith=11.5mA; PIth+30
= 7.8mW, Pratio,Ith+30
=0.88; Pmax
= 20.0mW
T=80ºC; Ith=14.5mA; PIth+30
= 7.1mW, Pratio,Ith+30
=0.80; Pmax
= 17.4mW
T=85ºC; Ith=15.6mA; PIth+30
= 6.9mW, Pratio,Ith+30
=0.78; Pmax
= 16.8mW
T=90ºC; Ith=16.6mA; PIth+30
= 7.0mW, Pratio,Ith+30
=0.78; Pmax
= 15.9mW
T=95ºC; Ith=17.9mA; PIth+30
= 6.7mW, Pratio,Ith+30
=0.76; Pmax
= 15.3mW
Key points:• High optical power enable
high coupling loss• Small threshold increasing up
to 95 C since high T0 • Small bias variation over T• Small efficiency degradation
over T
⇒ Constant eye quality with
constant modulation current!
Centre of eye power
Bias variation (0-85 °C)
Measured on chip on carrierMeasured on chip on carrier
Slope eff. ratio= 80%
110 °C
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Technologies for LRM application: EDC (Electronic Technologies for LRM application: EDC (Electronic
Dispersion Compensation)Dispersion Compensation)
•EDC uses adaptive electrical
filtering techniques to compensate
for limitations incurred during fiber
propagation:
- modal dispersion
- chromatic dispersion
- polarization modal
dispersion
•EDC can be realized in an
integrated circuit.
•EDC can enhance the performance
of existing transceivers and
enabling new applications.
EDC technology
10 Gbps to 300m over legacy
multimode fiberTX CDR/
LD
FP/DFB
LinTIA
220m MMF RX CDR
Electronic Dispersion
Compensation
algorithm
D
t1
D
t2
D
tn
LPF CDR
Signal
Feedback
Adaptive controller
t1 tn
EQ
Why?
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Modal dispersion in MM fibersModal dispersion in MM fibers
back
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Eye diagram in the XFP module
70 C module 4.5 dB e.r. 43%
mm
0 C module 4.5 dB e.r. 43% mm
0 10 20 30 40 50 60 70 80 90 1000
5
10
15
20
25
30
35
40
45
Current (mA); - 09-Aug-2002
Power (m
W)
20 °C
100 °C
40 °C
60°C
80 °C
90 °C
1270128012901300131013201330134013501360
-70
-60
-50
-40
-30
-20
-10
Wavelength (nm)
Rel. Amplitude (dB)
l Peak: 1314.0 nm; SMSR: 46 dB
T=100 C
1260127012801290130013101320133013401350
-80
-70
-60
-50
-40
-30
-20
-10
Wavelength (nm)
Rel. Amplitude (dB)
l Peak: 1306.7 nm; SMSR: 49 dB
T=20C
Agilent uncooled InGaAsP BH 10
Gb DFB for 10GBASE-LR product:
2001 results
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Spectral broadening of a direct modulated
DFB laser
timetime
“0”
“1”
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Dispersion penalty
Back-
to
back
After
a fibre
link
TX output RX optical input Decision input
Pulse broadening causes intersymbol interference (ISI) and then eye closure :
less signal for the same received power
Noise depends on receiver, not on link : same noise
To get the same S/N more input power is needed : this is dispersion penalty
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Dispersion penalty at 2.5 Gb, 80 km, for a
directly modulated DFB laser
-35 -34 -33 -32 -31 -30 -29 -28 -27 -26
1e-3
1e-4
1e-5
1e-6
1e-7
1e-8
1e-9
1e-10
1e-11
1e-12
Optical input power [dBm]
BER
file: b28t20bb.; Sens. 10
-10: -29.6
file: b28t2080km.; Sens. 10
-10: -26.5
0, and 80 km
3.1 dB DP
DP
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Electro-absorption
Modulated DFB Laser
(EML)
Electro-absorption
Modulated DFB Laser
(EML)
• Device based on the monolithic integration between a DFB laser
and an Electro-Absorption Modulator (EAM).
• The DFB is biased at a constant current (CW).
• The EAM switch from transparency to opacity by applying
modulated voltage (HF signal).
DMDM--DFBDFB EMLEML
Key advantage of EML: The high frequency response is directly related to the fast dynamics of the modulator and not to the dynamic of the DFB laser: better eye quality, lower dispersion
penaltyCarrier relaxation
in DFB laser
Integrated EAM-DFB (EML)
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10Gb/ s filtered eye
10Gb/ s eye after 50km SMF
10Gb/ s unfiltered eye
BER test at 0, 50km SMF
0.6dB0 km
50 km SMF
10 Gb/s eye after 100km SMF BER test at 0,100km SMF
0.6dB
100 km SMF
0 km
50°C operation of 1550 nm 10Gb/s EML
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And what next?
• Economic crisis ⇒⇒⇒⇒ profitability of Optics low since 2001;
• BUT
- need for more speed and ability of transport more data remains unsatisfied
- 100Gb/s Ethernet standardized and planned
- 1Tb/s Ethernet is starting to be discussed
• So Low cost, low volumes (right now, especially in telecom) applications
- Many believe that photonic integration is the only solution of the problem, like “discrete transistor versus ICs”
- Particularly true for telecom (data formats…)
- R&D still in good shape? Surely hit by the downturn…
Sources: Optical Fiber Conference 2009 and related overviews;Sources: Optical Fiber Conference 2009 and related overviews;
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40 and 100 Gb/s standard
• (IEEE P802.3ba)
- for 40Gb/s (40GBASE – SR4, 850nm, 4 x 10GbE; 40GBASE – LR4, 1300nm, 4 x 10GbE CWDM)
- for 100 Gb/s (100GBASE – SR10, 850 nm, 10 x 10GbE; 100GBASE – LR4, 1300 nm, 4 x 25GbE, DWDM)
• 16G FC standard for Fiber channel
• Standard and MSA have focused the technology development:
- 16G FC transceiver SFP+ (Avago 980, Optnext 1300)
- First 40Gb/s and 100Gb/s CFP MSA (Multi-Source Agreement) Optnext, Finisar
• Pushing the DFB technology up to 25Gb/s uncooled !
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DFB technology: beyond the limits….
• OFC session: Uncooled and semicooled DFB laser sources at 25 and 40 Gb/s
- Key players: Avago, Finisar, Optnext/Hitachi, Fujitsu, NTT
• Avago: best eye quality up to 70C, 25Gb/s
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… but manufacturability
is key!
DF019DF013DF011DF007
12
10
8
6
4
2
0
Wafer
Threshold_Front
Boxplot of Threshold_Front
BoxPlot of Threshold / Max. Power / SMSR for 4 wafers• Several hundredths chip/wafer automatically tested
• Tight statistics
• Good reproducibility wafer to wafer
���� Uniform / high yield technological processDF019DF013DF011DF007
35
30
25
20
15
10
5
0
Wafer
Power__Imax_Front
Boxplot of Power__Imax_Front
DF019DF013DF011DF007
50
45
40
35
30
Wafer
SMSR__100mA
Boxplot of SMSR__100mA
Accelerated Life test
• ALT conditions: 95 ºC, 80 mA ACC
• Burn In conditions: 100 ºC, 90 mA, 24 h
•• Devices stable over > 5000Devices stable over > 5000
���� reliable technological process
Delta Output Power (%)
-40
-30
-20
-10
0
10
20
30
40
0 1000 2000 3000 4000 5000 6000
aging time T (h)
Delta Output Power (%)
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Photonic integration trends
• On telecom network:
- Low cost, 100Gb/s, modulation format…
• ⇒⇒⇒⇒ Photonics on InP
- Infinera, (OFC2009, OThN2) Transmitter PIC for 10-Channel x 40Gb/s per Channel Polarization-Multiplexed RZ-DQPSK Modulation
- High complexity; system on a chip….
-
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Passive and tuning
waveguides
DBR and SOA active
waveguide
Wide tunable laser: DBR Array
InP Monolithically
integrated
DBR Array + PICBent
waveguide
sMMI
SOA
4 grating pitches (EBL)
⇒⇒⇒⇒ 10 nm spaced
Bragg Wavelengths
Bent
output
Output beam
400 um
1670 um
40 um
Medium
tuning
DBR
array
Paoletti et al. ECOC 2003Paoletti et al. ECOC 2003
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Device results: emitted spectrum
1.52 1.53 1.54 1.55 1.56 1.57 1.58 1.59 1.6-70
-60
-50
-40
-30
-20
-10
0
chip4-M35-2 @ 20°C: Iact
=50mA
Wavelength - nm -
Rel. Optical Power -dB -
41 nm tuning range
Paoletti et al. ECOC 2003Paoletti et al. ECOC 2003
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Revolution on active material:Is Quantum Dot ready to go?
OFC2009, OWJ1, OFC2009, OWJ1, ““HighHigh--Speed and TemperatureSpeed and Temperature--Insensitive Operation in 1.3Insensitive Operation in 1.3--µµm m InAs/GaAsInAs/GaAsHighHigh--Density Quantum Dot LasersDensity Quantum Dot Lasers”” , Fujitsu, Fujitsu
200 um long 1.3um ridge FP laser, with amazing performances… on
GaAs . Announced to be “ready for production”….
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The Turin Technology
Centre (TTC)
Via G. Schiaparelli 12 10148 Torino ItalyVia G. Schiaparelli 12 10148 Torino Italy
Acquisition by Agilent Technologies 19 April 2000
Activity: R&D and Production (laser chip)
• Short term Development projects (transceivers @ 2.5 Gbit/s and @10 Gbit/s)
• Medium term Research projects for active and passive devices
• Development and Production of 10G FP/DFB/EML laser source
Facilities
• EPI (2 MOCVD), material characterization, processing (including EBL), die fab (singulation, coating, testing, assembly and reliability tests)
Expertise: optoelectronic and photonic technologies
• New devices and components conception and design
• Semiconductors
• Device design, prototyping and characterisation
Offices surface: 1005 m2
Laboratory surface: 3281 m2
Roberto Paoletti, Pavia
22 June, 2009
Page 46
Key StrengthDeveloping a reliable technology….
• Reliability has always been the key strength in a III-V world
• Customer reliability expectation is almost compared to the ‘telecom”field, but for low cost – consumer products
⇒⇒⇒⇒ Reliability is the key investment in the III-V area
Example: DFB (SFP+, XFP)
qualified for Cisco:
• 7 M device* hours
• Long endurance test
Enormous investments…
Roberto Paoletti, Pavia
22 June, 2009
Page 47
Key StrengthTesting a production volume….
• Testing is one of the most expensive part in the III-V production
• Typical application require 100% testing of the laser chip!
• Only key team have testing capability suitable for mass-production
- Investment not scalable for start-up
⇒⇒⇒⇒ (low cost) testing developing is a key strength.. Also from R&D design perspective
SMSR 30 mA (dB)
0.00
4.00
8.00
12.00
16.00
20.00
24.00
28.00
32.00
36.00
40.00
44.00
48.00
DA012__Y2 (346)
DA012__Y4 (264)
DA012__Y8 (336)
DA013__Y1 (103)
DA013__Y3 (246)
DA017__Y2 (357)
DA017__Y4 (316)
DA017__Y6 (247)
DA022__Y2 (249)
DA022__Y5 (98)
DA022__Y7 (377)
DA043__Y2 (490)
DA043__Y4 (519)
DA044__Y1 (417)
DA044__Y3 (761)
DA046__Y2 (387)
DA046__Y4 (427)
DA046__Y6 (628)
DA047__Y2 (110)
DA047__Y4 (570)
DA054Z_Y1 (204)
DA054Z_Y3 (321)
DA055U_Y2 (289)
med 25% 75%
Example: DFB qualificationExample: DFB qualification•• Statistic of 9 qual wafers:Statistic of 9 qual wafers:•• Based on 15K chip tested across 8 Based on 15K chip tested across 8 waferswafers
Roberto Paoletti, Pavia
22 June, 2009
Page 48
www avagotech.com
www.torinoscienza.it/lab-vr/agilent
(visita virtuale ai laboratori TTC)
San Jose
-9h
Torino
Singapore
+6h
Chip development requires team work
across the globe: not an easy task!
Roberto Paoletti, Pavia
22 June, 2009
Page 49
The end!• Books
- G. Guekos, Photonic Devices, Springer, 1999, ISBN 3-540-64318-4
- L. A. Coldren, S. W. Corzine, “Diode lasers and photonic integrated circuits”, John Wiley and sons, inc.,
- P. Vasil’ev, “Ultrafast diode laser”, Artec House Boston-London
- K. Petermann, “Laser Diode Modulation” and Noise, Dordrecht, The Netherlands: Kluwer Academic Publishers
• Related published paper
- F. Delpiano, R. Paoletti, P. Audagnotto and R. Puleo, "High Frequency Modelling and Characterisation of High Performance DFB Laser Modules", IEEE Transaction on Components, Hybrids, and Manufacturing Technology, Part B, Vol. 17, No 3, pp. 412-417, august 1994.
- R. Paoletti, D. Bertone, A. Bricconi, R. Fang, L. Greborio, G. Magnetti, M. Meliga, "Comparison of Optical and Electrical Modulation Bandwidths in three different 1.55 µµµµm InGaAsP Buried Laser Structures", SPIE'S International Symposia - Photonics West '96, pp. 296-305, 30 Jan. - 1 Febr. 1996, S. Josè, CA, USA.
- R. Paoletti, M. Meliga, I. Montrosset, “Optical Modulation Technique for Carrier Lifetime Measurement in Semiconductor Lasers”, IEEE Photonics Technology Letters, Vol. 8, No. 11, pp. 1447-1449, November 1996.
- R. Paoletti, M. Meliga, G. Oliveti, M. Puleo, G. Rossi, L. Senepa, “10 Gbit/S Ultra-Low Chirp 1.55µµµµM Directly Modulated Hybrid Fiber Grating - Semiconductor Laser Source”, 23rd European Conference on Optical Communication ECOC '97, Mo 3B. 22-25 September 1997, Edimburgh (UK).
- R. Y. Fang, D. Bertone, M. Meliga, Montrosset*, S. Murgia, G. Morello, G. Magnetti, G. Oliveti, R. Paoletti, “A simple structure 1.55 µµµµm InGaAsP/InP Spot Size Converted (SSC) laser”, IEEE Photonics Technology Letters, Vol. 10, No. 6, pp. 775-777, June 1998.
- G. Rossi, R. Paoletti, M. Meliga, “SPICE simulation for analysis and design of fast 1.55 µµµµm MQW laser diodes”, IEEE Journal of Lightwave Technology, Vol. 16, No. 7, July 1998.
- R. Paoletti, M. Agresti, G. Burns, G. Berry, D. Bertone. P. Charles, P. Crump, A. Davies, R.Y. Fang, R. Ghin, P. Gotta, M. Holm, C. Kompocholis, G. Magnetti, J. Massa, G. Meneghini, G. Rossi, P. Ryder, A. Taylor, P. Valenti and M. Meliga, "100 °°°°C, 10 Gb/s directly modulated InGaAsP DFB lasers for uncooled Ethernet applications", post-deadline at European Conference on Optical Communication ECOC '2001, October 2001,Amstedam (NL).
- R. Paoletti, M. Meliga, "Uncooled, high speed DFB lasers for Gigabit Ethernet applications", invited paper at SPIE'S International Symposia - Photonics West Optoelectronics 20021, 19 - 25 Jan. 2002, S. Josè, CA, USA.
- R. Paoletti, C. Coriasso, M. Agresti, P. Gotta, G. Magnetti, A. Moro, D. Sarocchi, D. Soderstrom, C. Cacciatore, L. Fratta, M. Vallone, A. Stano, E. Liotti, P. Valenti, G. Roggero, G. Fornuto, G. Burns, R.Harrell, P. Charles, D. Clark, G. Berry and M. Meliga, "Small chip size, low power consumption, fully electronic controlled tunable laser source with 40 nm tuning range and 20 mW output power for WDM applications", ECOC 2003, 21 - 25 Sept. 2003, Rimini, Italy
- R. Paoletti, M. Agresti, D. Bertone, L. Bianco, C. Bruschi, A. Buccieri, R. Campi, C.Dorigoni, P. Gotta, M. Liotti, G. Magnetti, P. Montangero, G. Morello, C. Rigo, E. Riva, D. Soderstrom, S. Stano, P. Valenti, M. Vallone, M. Meliga" Highly reliable and high yield 1300 nm InGaAlAs directly modulated ridge Fabry-Perot lasers, operating at 10 Gb/s, up to 110 ºC, with constant current swing ", Post deadline at Optical Fiber Conference OFC 2005, Anaheim (CA)