Transcript Initiative on More-than-Moore roadmapping

“More-than-Moore” ERD
Michel Brillouët – U-In Chung
+ other coming contributions
April 10, 2011
MtM WG - ITRS ERD - Potsdam
1
“More-than-Moore” ERD: technical background
Example: Wireless Sensor Networks
rf wave
Higher level function
011001010…
control
LNA
ADC
Intermediate level
function
nanoradio
LO
PA
antenna
filter
oscillator
Lower level functions
April 10, 2011
mixer
LO
nanoantenna
Energy
DAC
2011 ITRS-ERD MtM devices
switch?
ADC
spin-torque oscillator
NEMS nanoresonator
converter
C-electronics
MtM WG - ITRS ERD - Potsdam
RTD?
SET?
2
“More-than-Moore” ERD: structure of the contributions
• identify key figures of merit for the device / function
(see general MtM methodology from the ITRS White Paper)
• if available give figures for the state-of-the-art “classical” devices
and their predicted value “at the end of the roadmap”
(if possible refer to existing tables in the other ITRS chapters)
• list potential emerging devices
and give figures for demonstrated
and extrapolated performances
along the same metrics
• list a first set of significant publications supporting this exercise
• add any qualitative statement as needed
April 10, 2011
MtM WG - ITRS ERD - Potsdam
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“More-than-Moore” ERD: working group
introduction
rationales, technical content, method, etc.
spin-torque oscillator
C-electronics
as rf transistor, mixer…
M. Brillouët
A. Chen
U-In Chung
S. Das
rectifier
or any other non-linear emerging device
A. Ionescu
NEMS nanoresonator
RTD?
assess if there is significant activity
SET?
only if someone volunteers
M. Brillouët (p.i.)
Other volunteers: H. Bennett, S. Deleonibus, Y. Obeng
[+ G. Bourianoff, E. De Benedictis, S. Shankar??]
April 10, 2011
MtM WG - ITRS ERD - Potsdam
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Figures of merit for rf ERD
M. Brillouët
April 10, 2011
MtM WG - ITRS ERD - Potsdam
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rf-ams transistors
rf-ams CMOS
rf-ams bipolar
General Analog NPN Parameters
Performance RF/Analog [1]
1/f-noise (µV²·µm²/Hz)
Supply voltage (V) [2]
s current matching (%·µm)
Tox (nm) [2]
High Speed NPN (HS NPN) - Common to mmWave Table
Gate Length (nm) [2]
Emitter width (nm)
gm/gds at 5·Lmin-digital [3]
Peak fT (GHz)
1/f-noise (µV²·µm²/Hz) [4]
Peak fMAX (GHz)
s Vth matching (mV·µm) [5]
Maximum Available Gain (dB) @ 60 GHz
Ids (µA/µm) [6]
Maximum Available Gain (dB) @ 94 GHz
Peak Ft (GHz) [7]
NFMIN (dB) @ 60 GHz
Peak Fmax (GHz) [8]
BVCEO (V)
NFmin (dB) [9]
JC at Peak fT (mA/µm2)
High Speed PNP (HS PNP)
Precision Analog/RF Driver [1]
Emitter width (nm)
Supply voltage (V)
Tox (nm) [10]
Peak fT (GHz)
Gate Length (nm) [10]
Peak fMAX (GHz)
• gm/gds
• matching
• noise (1/f, NF)
• ft, fMax
@ some BV
BVCEO (V)
gm/gds at 10·Lmin-digital [11]
Power Amplifier NPN (PA NPN) - Common to PA Table
1/f Noise (µV²·µm²/Hz) [4]
Emitter width (nm)
s Vth matching (mV·µm) [5]
Peak fT (GHz) [VCB = 2 V]
Peak Ft (GHz) [7]
Peak fMAX (GHz)
Peak Fmax (GHz) [8]
Maximum Stable Gain (dB) @ 900 MHz
Availability of optional analog / High-voltage FETs
Maximum Stable Gain (dB) @ 1.8 GHz
BVCEO (V)
BVCBO (V)
April 10, 2011
from ITRS Wireless chapter
MtM WG - ITRS ERD - Potsdam
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Transistors for power amplifier
III-V HBT
Si MOS
SiGe HBT
III-V HBT transistor
Silicon MOSFET transistor
SiGe HBT transistor [9]
Fmax (at Vcc) (GHz)
Tox (PA) (Å) [8]
Fmax (GHz)
BVCBO (V)
Fmax (at Vdd)
BVCBO (V)
BVDSS (V)
Linear efficiency (%) [1]
Linear efficiency (%) [1]
Area (mm2) [2]
Linear efficiency (%) [1]
PA Area (mm2) [2]
Cost/mm2 (US$) [3]
PA Area (mm2) [2]
Cost/mm2 (US$) [3]
Cost/mm2 (US$) [3]
• fMax
• linear efficiency
@ some BV
April 10, 2011
from ITRS Wireless chapter
MtM WG - ITRS ERD - Potsdam
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Base station devices
Si LDMOS
GaN FET
Cost ($$/Watt) [2]
Cost ($$/Watt) [2]
Operating voltage (V)
Operating voltage (V)
Cds / W (pF/Watt) [3]
Cds / W (pF/Watt) [3]
P1dB power (Watt) [4]
P1dB power (Watt) [4]
P1dB power density (Watt/mm) [5]
P1dB power density (Watt/mm) [5]
P1dB Drain Efficiency (%) [6]
P1dB Drain Efficiency (%) [6]
Peak Drain Efficiency (%) [7]
Peak Drain Efficiency (%) [7]
Gain Compression at Peak Efficiency (dB) [8]
Gain Compression at Peak Efficiency (dB) [8]
High Efficiency Architecture drain eff at linearity spec @8dB OBO (%) [9]
High Efficiency Architecture drain eff at linearity spec @8dB OBO (%) [9]
etc.
April 10, 2011
MtM WG - ITRS ERD - Potsdam
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Conclusion
• device FoM useful for comparing with graphene / C-based rf transistors
• FoM and state-of-the-art / “end of the roadmap” have to be defined for:
– oscillators
– switch
– ADC
April 10, 2011
MtM WG - ITRS ERD - Potsdam
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Graphene / C-based electronics
for rf applications
U-In Chung + M. Brillouët
April 10, 2011
MtM WG - ITRS ERD - Potsdam
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Graphene RF Transistors
Key figures of merit of Graphene RF Transistor
Possibility of THz cutoff frequency
- Sub-100-nm transistors were fabricated using nanowire gate.
- High Fermi velocity of carriers in graphene, resulting in high drift velocity (~ 4 x 107 cm/s)
in channel, makes fT ~ 1THz for sub 70 nm channel length device
Comparison to Current Devices
Highest cutoff frequency of Current Devices
- GaAs mHEMT with a 20-nm gate: 660 GHz
- Si MOSFET with a 29-nm gate: 485 GHz.
- GaAs pHEMT with a 100-nm gate: 152 GHz.
SAMSUNG [3]
UCLA [1]
IBM (Science)
F.Schwierz, “Graphene Transistors,” Nature Nanotechnology 5, 487 (2010)
Left: RF Transistors on 6 inch wafer
Right: Single RF Transistor
Potential applications
Needs and Destination of next generation mobile
Low Noise Amplifier
Mixer
Challenges
Defect-free monolayer graphene growth
: CVD graphene has satisfactory uniformity of thickness[7]but transfer process, which is
prerequisite for CVD graphene, generate tearing of graphene.
: epitaxial one has no need for transfer, therefore no issue of transfer process, but
unsatisfactory uniformity of thickness[5].
Graphene-dielectric, graphene-metal inferface
: Graphene is highly inert material, which reduces the adhesion between graphene and dielectric
or metal.
: Charge impurities on the SiO2 surface reduces mobility of graphene.
: Hexagonal boron nitride is known as best surface for graphene, however, the low temperature
growth method would need to be developed.
References
[1]L. Liao, Y.-C. Lin, M.Bao, R. Cheng, J.Bai, Y. Liu, Y.Qu, K. L. Wang, Y. HuangX.Duan, “High-speed graphene
transistors with a self-aligned nanowire gate,” Nature 467, 305 (2010)
[2]Ph. Avouris, Y.-M. Lin, F. Xia, D.B. Farmer, T. Mueller, C. Dimitrakopoulos, K. Jenkins, A. Grill, “Graphene-Based
Fast Electronics and Optoelectronics,” IEDM 23.1 (2010)
[3]J. Lee, H.-J. Chung, J. Lee, H. Shin, J. Heo, H. Yang, S.-H. Lee, J. Shin, S. Seo, U. Chung, I. Yoo, K. Kim, “RF
Performance of Pre-Patterned Locally-Embedded-Back-Gate Graphene Device,” IEMD 23.5 (2010)
[4]X. Li, W.Cai, J. An, S. Kim, J. Nah, D. Yang, R.Piner, A.Velamakanni, I. Jung, E.Tutuc, S. K. Banerjee, L. Colombo, R.
S. Ruoff,“Large-Area Synthesis of High-Quality and Uniform Graphene Films on Copper Foils,” Science 324,
1312 (2009)
[5] C. Berger, Z. Song, T. Li, X. Li, A. Y. Ogbazghi, R.Feng, Z. Dai, A. N. Marchenkov, E. H. Conrad, P. N. First, W. A.
de Heer, “Ultrathin Epitaxial Graphite: 2D Electron Gas Properties and a Route toward Graphene-based
Nanoelectronics,” J. Phys. Chem. B 108, 19912 (2004)
[6]J.S.Moon, D. Curtis, S. Bui, T. Marshall, D. Wheeler, I. Valles, S. Kim, E. Wang, X. Weng, M. Fanton,“Top-Gated
Graphene Field-Effect Transistors Using Graphene on Si (111) Wafers,”IEEE Elect. Dev. Lett. 31, 1193 (2010)
[7]I.Jeon, H. Yang, S.-H.Lee, J.Heo, D. H. Seo, J. Shin, U-I.Chung, Z. G. Kim, H.-J. Chung, S.Seo, “Passivation of Metal
Surface States: Microscopic Origin for Uniform Monolayer Graphene by Low Temperature Chemical Vapor
Deposition,” ACS Nano 5, 1915 (2011)
[8]D.Waldmann, J.Jobst,F. Speck,T.Seyller, M. Krieger, H. B. Weber, “Bottom-gated epitaxial graphene,” Nature
Materials online edition (2011)
[9]L. Liao, J.Bai, R. Cheng, Y.-C. Lin, S. Jiang, Y.Qu, Y. Huang, X.Duan, “Sub-100 nm Channel Length Graphene
Transistors,” Nano Lett. 10, 3952 (2010)
[10] F.Schwierz, “Graphene Transistors,” Nature Nanotechnology 5, 487 (2010)
Latest results on ft / fMax
↘ parasitics (R, C…)
• gm/gds
• matching
• noise (1/f, NF)
• ft, fMax
@ some BV
↗ µ or v
from F. Schwierz Nature 472 41 (2011)
April 10, 2011
MtM WG - ITRS ERD - Potsdam
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rf CVD graphene transistors
gate
ox. Al + ALD Al2O3
Au/Pd contacts
134meV surface phonon
low Dit
59meV surface phonon
high Dit
DLC
SiO2
graphene
CVD on Cu
transfer w. PMMA
from static Id-Vd
• Dirac point -7V ⇐ fixed charge
• short channel effect (low Vg modulation of Id)
ft = 155GHz @Lg=40nm
from rf measurements
with de-embedding
no T dependency
fMax=20GHz @ Lg=550nm
fMax=13GHz @ Lg=140nm
Rc limited?
April 10, 2011
from Y. Wu Nature 472 74 (2011)
MtM WG - ITRS ERD - Potsdam
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Graphene for rf mixer
full-wave rectifier → frequency doubling
frequency mixer
if...
→ no odd-order inter-modulation
T. Palacios et al. IEEE Comm. Mag. 48 122 (2010)
April 10, 2011
MtM WG - ITRS ERD - Potsdam
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Graphene for rf NEMS
resonator
• high stiffness
• low density
rf switch
potential GHz
high current capability
(>7 kA/cm²)
Actual:
Q = 104 @5K
50-80 MHz
high Rc
C. Chen et al. Nature Nano 4 861 (2009)
K.M. Milaninia et al. APL 95 183105 (2009)
April 10, 2011
MtM WG - ITRS ERD - Potsdam
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Spin-Torque nano-oscillators
U-In Chung
April 10, 2011
MtM WG - ITRS ERD - Potsdam
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Spin torque oscillator
Key figures of merit of spin torque oscillator
1. frequency tunability ( 0.1 GHz ~ 40GHz or more)
- frequency can be tuned by external magnetic field or spin torque current
- frequency can also be tuned by magnetic materials and structures
Frequency tuning by different materials
Domain wall, Vortex <1GHz
GMR and MTJ Free & Pinned, <20GHz
AF exchange bias, SAF <40GHz
Additional H field >40 GHz
2. compact size (nanometer-sized oscillator)
- cost effective
STO size : ~ 100 ⅹ 100 nm2
Comparison to existing oscillator technologies
Crystal oscillator
VCO : L – high K
RF MEMS
STO
Size
< 1 cm3
< 1mm2
< 1mm2
< 1um2
Q
104 to 106
100 (enhanced
inductor)
1000
>1000 (GMR)
Output Power
40mW
1mW
(0 dBm)
1mW
(0 dBm)
< 1uW(currently)
Phase noise
-170dBc
-115 dBc
-110 dBc
N.A.
Power
consumption
[email protected]
0.4mA @ 0.82V
35mA @ 3.3V
1~5mA @ 1V
Tunable range
0%
10%
1%
10~100%
Agility
microseconds
nanoseconds
Potential applications
Needs and Destination of next generation mobile
Mobile convergence
Reconfigurability
Low power
Compact Design
STO : Wideband tunable nano-oscillator
Challenges
Auto-oscillation structures
: Spin torque oscillators have to eliminate the need for external magnetic field that
is used for most current experimental demonstrations.
: Now, three different approaches have been suggested for the auto-oscillation.
(perpendicular polarizer + in-plane free layer, wavy spin torque,
magnetic vortex structures)
Increase of Output Power
: The best metallic spin-transfer oscillators (MTJ oscillators) measured to date produce about
100 pW(~140 nW), while a few microwatts would likely be required for practical GHz
communication applications
: For the increase of output power, synchronization of spin torque oscillators has been proposed.
If phase locking is achieved for a collection of N oscillators, depending on how the devices are
wired, the maximum output power may grow as quickly as N2.
Phase noise (phase stability)
: For the most of telecommunication applications, low phase noise is extremely important issues.
The nonlinearities of spin torque oscillators are main sources of frequency instabilities, which
result in the broadening of linewidth of oscillation spectrum.
: Synchronization of spin torque oscillators is also one of the possible solutions.
References
Experimental Demonstrations
[2003] Nature_425_380_Microwave oscillation of nanomagnet driven by a spin-polarized current
[2004] Phys.Rev.Lett._92_027201_Direct current induced dynamics in CoFe NiFe point contacts
[2005] Nature_437_389_Mutual phase-locking of microwave spin torque nano-oscillators
[2005] Nature_437_393_Phase-locking in double point contact spin tranfer devices
[2008] Nat.Phys._04_803_Bais driven high power microwave emission from MgO based TMR devices
Auto-oscillation structures
[2007] Nat.Mat._06_447_Spin-torque oscillator using a perpendicular polarizer and a planar free layer
[2007] Nat.Phys._03_498_Magnetic vortex oscillator driven by d.c. spin-polarized current
[2007] Nat.Phys._03_492_Shaped angular dependence of the spin-transfer torque and
microwave generation without magnetic field
Issues of Challenges(phase noise)
[2008] Phys.Rev.Lett._100_017207_Generation Linewidth of an Auto-Oscillator with a Nonlinear Frequency
shift Spin-Torque Nano-Oscillator
[2009] Phys.Rev.Lett._102_257202_Temporal Coherence of MgO Based Magnetic Tunnel Junction Spin Torque
Oscillators
NEMS resonators
A. Ionescu
April 10, 2011
MtM WG - ITRS ERD - Potsdam
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RTD for ADC
M. Brillouët
April 10, 2011
MtM WG - ITRS ERD - Potsdam
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RTD for ADC
from the Web of Science (RTD AND ADC):
• only 6 papers from 1993 to 2011 (+2 from the references)
Benefits
• lower device count → low power consumption
• high speed (sub-ps switching time)
Issues
• use of III-V (InGaAs) [issue from the past?]
• low peak-to-valley current ratio
 variability
Proposal
• drop RTD for ADC as a specific topic
• extend a later survey into NDC-devices for ADC?
April 10, 2011
MtM WG - ITRS ERD - Potsdam
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Back-up slides
April 10, 2011
MtM WG - ITRS ERD - Potsdam
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