First
40 Giga-bits per
second Silicon Laser
Modulator
Dr. Mario Paniccia
Intel Fellow
Director, Photonics Technology
Lab
1
Agenda
y What We Are Announcing
y Silicon Photonics Re-cap
y Tera-Scale Computing
y Why is a Silicon Laser Modulator Needed?
y How Does the Silicon Laser Modulator Work
y Results
y Summary
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What We are Announcing
y Research Breakthrough: 1st 40 Giga-bits per second
Silicon Laser Modulator
– Fastest Laser Modulator made from silicon
– Capable of putting one’s and zeros on a beam of laser light – 40 Billion
time per second
y Intel’s Vision
– Use silicon and CMOS manufacturing techniques to build integrated optical
devices
– Build Tera-Bit per second optical links to enable Tera-scale computing
– One Tera-bit = 1,000 Billion bits
y Background
– Intel announced a One Giga-bit per second silicon laser modulator in 2004
– We have now achieved new milestone of 40 Giga-bits/second (Gb/s)
– Using 25 Silicon Laser Modulators at 40Gb/s we can build a Tera-bit per
second Optical link (25 x 40 Gb/s = 1 Terabit/s)
“Achieving 40Gb/s using a silicon laser modulator is a significant milestone for silicon photonics in that we’ve matched the data
transmission speed records set by fastest III-V optical devices available today,” said Justin Rattner, Intel Chief Technology
Officer. “We see silicon photonics at the heart of future, low cost optical interconnects for tera-scale computing.”
Justin Rattner, Intel Chief Technology Officer
3
The Photonic Dilemma
Fiber can carry much more bandwidth than
copper
However, it is much more expensive…..
4
Photonics: The technology of emission, transmission,
control and detection of light (photons) aka fiberoptics & opto-electronics
Today: Most photonic devices made with exotic
materials, expensive processing, complex packaging
Silicon Photonics Vision: Research effort to develop
photonic devices using silicon as base material and do
this using standard, high volume silicon
manufacturing techniques in existing fabs
Benefit: Bring volume economics to optical communications
5
Intel’s Silicon Photonics Research
Continuous Wave
Silicon Raman
1GHz ( Feb ‘04)
10 Gb/s (Apr ‘05)
Laser
(Feb ‘05)
40 Gb/s (Jul ’07)
Electrically
Pumped
Hybrid
Silicon laser
(September 2006)
We have achieved 40 Gb/s milestone
Focus is now on integration 6
ENERGY-EFFICIENT PERFORMANCE
Tera-leap to Parallelism:
10’s to 100’s
of cores
Era of
Tera-Scale
Computing
Quad-Core
Dual Core
Hyper-Threading
Instruction level parallelism
More performance
Using less energy
The days of
single-core chips
TIME
All this compute capability may require
high speed optical links
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Future Physical I/O for Tera-scale Computing
Core-Core: On Die
Interconnect fabric
Memory: Package
3D Stacking
Chip-Chip: Fast Copper
FR4 or Flex cables
Memory
Memory
TeraTera-scale CPU
Memory
CPU 2
Memory
Board-board interconnect: electrical or optical?
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Integrated Silicon
Photonics chips
A Terabit Optical Chip
Optical Fiber
Multiplexor
25 modulators at 40Gb/s
25 hybrid lasers
An future integrated terabit per second
optical link on a single chip
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Why is a Silicon Laser Modulator Needed
On –Off On-Off
As the laser heats and cools the pulses get distorted
This causes errors in the data transmission
1 01 01 01 01
On –Off On-Off
Solution: Externally Modulate the Laser
High fidelity pulses with ext. mod
1 01 01
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Wave Mechanics of Light
CONSTRUCTIVE INTERFERENCE
DESTRUCTIVE INTERFERENCE
π out of phase
(or 180 degrees)
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Silicon Laser Optical Modulator
PHASE
SHIFTER
OFF
Phase shift
OFF light stays
IN phase
Light is
split into
two paths
Digital “1”:
constructive
interference
PHASE
SHIFTER
OFF
Phase Shifter - A transistor-like device
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Silicon Laser Optical Modulator
PHASE
SHIFTER
ON
Light is OUT of
phase
Light is
split into
two paths
Digital “0”:
destructive
interference
PHASE
SHIFTER
ON
Phase Shifter - A transistor-like device
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Optically encoding Data
LASER
101010
DRIVER
PHASE
SHIFTER
ON
10101010
PHASE
SHIFTER
ON
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Silicon Laser Modulator
• This new generation modulator is smaller and consumes less power than the
first generation modulator that operated at 10 Gb/s
• Based on traveling wave design
• Optimized optical and electrical RF signaling characteristics (high speed
transmission traces, termination resistance matching, parasitics reduced)
• Results presented at an invited talk at the IPNRA (Integrated Photonics and
Nanophotonics Research and Applications) July 2007 Salt Lake City, Utah USA
Metal contact
Phase shifter
waveguide
Silicon modulator on PCB
SEM picture of p-n phase shifter
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40Gb/s Silicon Laser Modulator
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40Gb/s Data Transmission
Results presented at IPNRA
Optical Roll-off
Normalized Modulator Output (dB)
1
0
-1
-2
-3
-4
~30 GHz roll-off
-5
-6
-7
-8
0
1
10
Frequency (GHz)
40Gb/s Data Transmission
Optical 3 dB roll off ~30 GHz
Worlds Fastest Silicon Laser Modulator
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100
Integrating into a Tera-scale System
This transmitter
would be combined
with a receiver
Rx
Tx
Which could then be built into an
integrated, silicon photonic chip!!
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Integrating into a Tera-scale System
This integrated silicon photonic
chip could then be integrated
into computer boards
And this board could be
integrated into a Terascale system
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Summary
y Research Breakthrough: 1st 40 Giga-bits per second
Silicon Laser Modulator
– Fastest Laser Modulator made from silicon
– Capable of putting one’s and zeros on a beam of laser light – 40 Billion
time per second
y Intel’s Vision:
– Use silicon and CMOS manufacturing techniques to build integrated optical
devices
– Build Tera-Bit per second optical links to enable Tera-scale computing
– One Tera-bit = 1,000 Billion bits
y Background
– Intel announced a One Giga-bit per second silicon laser modulator in 2004
– We have now achieved new milestone of 40 Giga-bits/second (Gb/s)
– Using 25 Silicon Laser Modulators at 40Gb/s we can build a Tera-bit per
second Optical link (25 x 40 Gb/s = 1 Terabit/s)
“Achieving 40Gb/s using a silicon laser modulator is a significant milestone for silicon photonics in that we’ve matched the data
transmission speed records set by fastest III-V optical devices available today,” said Justin Rattner, Intel Chief Technology
Officer. “We see silicon photonics at the heart of future, low cost optical interconnects for tera-scale computing.”
Justin Rattner, Intel Chief Technology Officer
20
Thank You
More Information is at:
Research blog:
http://blogs.intel.com/research/
High res pictures and press info:
http://www.intel.com/pressroom/kits/research/4Gmodulator.htm
Silicon Photonics Web-site
http://www.intel.com/research/platform/sp/
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