roadmap to 100ge, a cwdm solution -...
TRANSCRIPT
1
Roadmap to 100 GbE, a CWDM Solution
IEEE 802.3 Higher Speed Study Group
IEEE 802.3 Higher Speed Study Group
Interim Meeting , Monterey CA
January 17-19, 20
Xavier Clairardin, Kotura
2
Proposed SMF Study Alternative
•CWDM laser array
–Un-cooled CWDM DML array
–1430 –1610nm, 20nm spacing
–ITU G.694.2 Grid
•10 GbsPINsarray
•Existing 10 GbsElectronics
•SOI Integration platform
–Mux/ Demuxintegrated Gratings
–Automated Flip Chip bonding
–Passive Alignment
–Non herm
etic package
–Small Photonic Chip fits in Small
Form
Factor MSA such as XENPAK
•100m –10km Reach over SMF
MUX DEMUX
10xPhotodiodes
Monitoring
Photodiodes
10 x CWDM DFB
Laser Arrays
10 x TIA10 x Laser Driver
Optical Output
100 GE
Optical Input
100 GE
Electrical Output
10 x 10 GE
Electrical Input
10 x 10 GE
1550nm 10x10 G un-cooled DML CWDM array
3
Leveraging Silicon Photonics
A platform
that integrates optics & electronics on the same
silicon chip using standard CMOS m
anufacturing techniques.
Electrons & Photons in Silicon
Silicon
SiO
2
p+ / n+ doped
metal
Optical beam
Array of CMOS Photonics Chips
4
Silicon Allows Very Small Mux/Demux
15mm
3.5mm
15mm
7mm
•CMOS Si process
•100’s of chips per wafer
•1/10 size of a standard AWG
•Small chip fit SFF MSA such XENPAK
5
Silicon DeMuxresponse over 10 CWDM channels
12nm
RX Demuxdesigned with 12nm Flat passband
•Allows 4nm for DFB registration
•Allows 8nm for variation of Demuxover 100oC
•Provides <-30dB adjacent channel x-talk.
DFB λ λλλ
registration: +/-2nm
6
MuxResponse over 10 CWDM channels
6.4nm
TX Muxdesigned with broad Gaussian 6.4nm Passband
allowing 4nm for DFB registration.
5pm/oC ∆λ/∆T difference between Si and InPover Temp Range
provides for 20oC for temperature differential across chip.
High therm
al conductivity of Si provides good therm
al management
DFB λ λ λ λ registration: +/-2nm
7
Waveguide Optical Coupling
•Three dim
ensional mode expander reduces waveguide coupling loss to
< 0.5 dB
•Total insertion loss of <1dB fiber-to-fiberdemonstrated
•Reduced Back facet reflection (<-50dB)
•Im
proved PDL (<0.05dB)
8
-1.5
-1-0.5
00.5
11.5
-5
-4.5-4
-3.5-3
-2.5-2
-1.5-1
-0.50
Offset(um)
coupling Loss(dB)
Horizontal
Vertical
02
46
810
-3
-2.5-2
-1.5-1
-0.50
Distance(um)
coupling Loss(dB)
Coupling Loss ~ -1.2dB with passive alignment tolerance:
X±0.5um, Y ±0.3um, Z = 3um±1um
DFB Laser Coupling to a W
aveguide
9
Laser Hybridization –
Automated passive alignment
Key Strengths
•Tuning capability is Key for DWDM applications
•Silicon has similar ∆n/∆T as III/V
•High therm
al conductivity enables high power dissipation and good temp control
•No compromise in perform
ance
•Low cost process
•Very high yield
Key Components
•Lasers
•Detectors
•SOAs& LOAs
•SLDs
Laser
Monitor PD
Waveguides
10
Photodiode Hybridization
Active area
Pn
Absorptive area
p-n
junction collects
photo-current
Phase 1: Integrated Mirror with
Surface Mount Photodiode
Phase 2: Integrated
Power Monitor
Si Ge
Future Photodiode
Integration
11
CYOPTICS CWDM Laser Array
12
MUX
Monitoring
Photodiodes
10 x CWDM DFB
Laser Arrays
10 x Laser Driver
Electrical Input
10 x 10 GE
100 GbEthernet
DEMUX
10xPhotodiodes
10 x TIA
Electrical Output
10 x 10 GE10X10 GE Link Budget Considerations
13
Economic Feasibility
14
Example of Photonic integration : Next Gen FTTH Triplexer
Laser: Passive
Auto-aligned
Passive Fiber
Attach
VOAs
Surface
Mount PD
Monolithically
Integrated Front
Facet Monitor
Mux/ Demux
Grating Element
Absorbers
n
Si
15
10 GE Landscape
10GBASE-EW
10GBASE-ER
10GBASE-LW
10GBASE-LR
10GBASE-LX4
1310nm LAN / WWDM SMF
10GBASE-SW
850nm W
AN
Serial MMF
10GBASE-SR
850nm LAN
Serial MMF 65m
300m
10Km
40Km
1310nm LAN / WWDM M
MF
1550nm W
AN / Serial SMF
1550nm LAN / Serial SMF
1310nm W
AN / Serial SMF
1310nm LAN / Serial SMF
16
100 GE Current Reach/PMD Objectives
Extended Reach
Long Reach
Interm
ediate Reach
Short Reach
MMF
100m
300m
2Km
10Km
40Km
Current Objectives
Potential Interm
ediate
SMF
SMF
SMF
17
Roadmap to Lower Cost & Higher Perform
ance
Integration“D
o whatever you can in CMOS and the rest in InP,” (Infinera)
•Start with silicon m
ux/demux& hybridization platform
–Silicon Photonics: Mux/demux, Hybridization platform
–Leverage existing chip sets at 10GE: TIA’s, laser drivers
–InPplatform
: 10X10GE CWDM DFB lasers array, monitors, detectors
•Im
plement monitors in silicon
–InP: 5X 20 GE CWDM DFB laser array, detectors
–Electronic chips: commercial TIA’s, laser drivers
•Replace laser array with broad light source
•Im
plement modulators & detectors in silicon
–InP: Low cost broadband light source
Time