This document describes a 1D simulator for charge trapping flash memory. The simulator models programming, erasing, and retention by solving equations for Poisson, tunneling, continuity, and Shockley-Read-Hall. It was used to understand the impact of physical parameters and predict experimental data for SONOS and TANOS flash. The simulator extracted non-uniform trap distributions near interfaces and provided insight into improving charge trapping flash memory design.
Battery research study; Amsterdam RAI; 10-10-2012; European Utility week 2012Machiel Joosse
How reliable are theoretical battery lifetime calculations compared with reality?
The Dutch DSO’s Netherlands (within Netbeheer Nederland), joined forces to carry out a unique study of the predicted and actual battery lifetime. In this study, batteries were examined from gas meters that had already been operating for 4-5 years. The results were promising: after 4-5 years: the actual (practical) lifetime of the batteries examined turned out to be in line with the predicted (theoretical) values.
Battery research study; Amsterdam RAI; 10-10-2012; European Utility week 2012Machiel Joosse
How reliable are theoretical battery lifetime calculations compared with reality?
The Dutch DSO’s Netherlands (within Netbeheer Nederland), joined forces to carry out a unique study of the predicted and actual battery lifetime. In this study, batteries were examined from gas meters that had already been operating for 4-5 years. The results were promising: after 4-5 years: the actual (practical) lifetime of the batteries examined turned out to be in line with the predicted (theoretical) values.
This handout accompanies a presentation, "Data-Driven Enterprise off Any Beat," by Manuel Torres, enterprise editor for The Times-Picayune | Nola.com, for NewsTrain in Monroe, La., on Oct. 15-16, 2015. It offers tips on getting public records in general and by state, as well as resources at the federal level. NewsTrain is a training initiative of Associated Press Media Editors: http://bit.ly/NewsTrain
Depression’s Impact on Relationships and Relationships’ Impact on DepressionUCSF Dept. of Psychiatry
Presentation by Beverly Lehr, PhD, and Katherine Straznickas, PhD, at the UCSF Depression Center's "Depression: Pathways to Resilience and Recovery" event on September 13, 2014.
Prediction of the Open-Water Performance of Ducted Propellers With a Panel Me...João Baltazar
In the present work, a comparison between the results obtained by a panel code with a RANS code is made to obtain a better insight on the viscous effects of the ducted propeller and on the limitations of the inviscid flow model, especially near bollard pull conditions or low advance ratios, which are important in the design stage. The analysis is carried out for propeller Ka4-70 operating inside duct 19A. From the comparison, several modelling aspects are studied for improvement of the inviscid (potential) flow solution. Finally, the experimental open-water data is compared with the panel method and RANS solutions. A strong influence of the blade wake pitch, especially near the blade tip, on the ducted propeller force predictions is seen. A reduction of the pitch of the gap strip is proposed for improvement of the performance prediction at low advance ratios.
Under a Compulsory Course of "Materials Physics and Technology for Nanoelectronics" a team of BE Students of Nanotechnology, Nanoelectronics and Bionnotechnology prepared this seminar for Prof. Marc Heyns, marc.heyns@imec.be Kapeldreef 75, B-3001 Heverlee IMEC Building IV, room 2.33
Tel: 016 281 348
SWCNT Growth from Chiral and Achiral Carbon Nanorings: Prediction of Chiralit...Stephan Irle
Catalyst-free, chirality-controlled growth of chiral and achiral single-walled carbon nanotubes (SWCNTs) from organic precursors is demonstrated using quantum chemical simulations [1]. Growth of (4,3), (6,5), (6,1), (10,1), (6,6) and (8,0) SWCNTs was induced by ethynyl radical (C2H) addition to organic precursors. These simulations show a strong dependence of the SWCNT growth rate on the chiral angle, θ. The SWCNT diameter however does not influence the SWCNT growth rate under these conditions. This agreement with a previously proposed screw-dislocation-like model of transition metal-catalyzed SWCNT growth rates [2] indicates that the SWCNT growth rate is an intrinsic property of the SWCNT edge itself. Conversely, we predict that the rate of local SWCNT growth via Diels-Alder cycloaddition of C2H2 is strongly influenced by the diameter of the SWCNT. We therefore predict the existence of a maximum local growth rate for an optimum diameter/chirality combination at a given C2H/C2H2 ratio. We also find that the ability of a SWCNT to avoid defect formation during growth is an intrinsic quality of the SWCNT edge.
References:
[1] Li, H.-B.; Page, A. J.; Irle, S.; Morokuma, K. J. Am. Chem. Soc. 2012, 134, 15887-15896.
[2] Ding, F.; Harutyunyan, A. R.; Yakobson, B. I. Proc. Natl. Acad. Sci. 2009, 106, 2506-2509.
This handout accompanies a presentation, "Data-Driven Enterprise off Any Beat," by Manuel Torres, enterprise editor for The Times-Picayune | Nola.com, for NewsTrain in Monroe, La., on Oct. 15-16, 2015. It offers tips on getting public records in general and by state, as well as resources at the federal level. NewsTrain is a training initiative of Associated Press Media Editors: http://bit.ly/NewsTrain
Depression’s Impact on Relationships and Relationships’ Impact on DepressionUCSF Dept. of Psychiatry
Presentation by Beverly Lehr, PhD, and Katherine Straznickas, PhD, at the UCSF Depression Center's "Depression: Pathways to Resilience and Recovery" event on September 13, 2014.
Prediction of the Open-Water Performance of Ducted Propellers With a Panel Me...João Baltazar
In the present work, a comparison between the results obtained by a panel code with a RANS code is made to obtain a better insight on the viscous effects of the ducted propeller and on the limitations of the inviscid flow model, especially near bollard pull conditions or low advance ratios, which are important in the design stage. The analysis is carried out for propeller Ka4-70 operating inside duct 19A. From the comparison, several modelling aspects are studied for improvement of the inviscid (potential) flow solution. Finally, the experimental open-water data is compared with the panel method and RANS solutions. A strong influence of the blade wake pitch, especially near the blade tip, on the ducted propeller force predictions is seen. A reduction of the pitch of the gap strip is proposed for improvement of the performance prediction at low advance ratios.
Under a Compulsory Course of "Materials Physics and Technology for Nanoelectronics" a team of BE Students of Nanotechnology, Nanoelectronics and Bionnotechnology prepared this seminar for Prof. Marc Heyns, marc.heyns@imec.be Kapeldreef 75, B-3001 Heverlee IMEC Building IV, room 2.33
Tel: 016 281 348
SWCNT Growth from Chiral and Achiral Carbon Nanorings: Prediction of Chiralit...Stephan Irle
Catalyst-free, chirality-controlled growth of chiral and achiral single-walled carbon nanotubes (SWCNTs) from organic precursors is demonstrated using quantum chemical simulations [1]. Growth of (4,3), (6,5), (6,1), (10,1), (6,6) and (8,0) SWCNTs was induced by ethynyl radical (C2H) addition to organic precursors. These simulations show a strong dependence of the SWCNT growth rate on the chiral angle, θ. The SWCNT diameter however does not influence the SWCNT growth rate under these conditions. This agreement with a previously proposed screw-dislocation-like model of transition metal-catalyzed SWCNT growth rates [2] indicates that the SWCNT growth rate is an intrinsic property of the SWCNT edge itself. Conversely, we predict that the rate of local SWCNT growth via Diels-Alder cycloaddition of C2H2 is strongly influenced by the diameter of the SWCNT. We therefore predict the existence of a maximum local growth rate for an optimum diameter/chirality combination at a given C2H/C2H2 ratio. We also find that the ability of a SWCNT to avoid defect formation during growth is an intrinsic quality of the SWCNT edge.
References:
[1] Li, H.-B.; Page, A. J.; Irle, S.; Morokuma, K. J. Am. Chem. Soc. 2012, 134, 15887-15896.
[2] Ding, F.; Harutyunyan, A. R.; Yakobson, B. I. Proc. Natl. Acad. Sci. 2009, 106, 2506-2509.
What can we learn from molecular dynamics simulations of carbon nanotube and ...Stephan Irle
We present the results of nonequilibrium molecular dynamics (MD) simulations of catalytic and non-catalytic carbon nanostructure formation processes, including single-walled carbon nanotube (SWCNT) and graphene nucleation and growth. In the talk, we discuss the significance of the findings in the light of more traditional, static descriptions of growth reaction mechanisms, and highlight differences as well as commonalities.
Design, test and mathematica modeling of parabolic trough solat collectors (P...Marco Sotte
Parabolic Trough Collectors are widespread in CSP applications. Their adoption is less developed in industrial heat demand applications. In the present thesis the design and test of two prototypes of PTC for the thermal loads in the range 80 - 250 °C is described. A mathematical model has also been developed to predict optical efficiency and thermal losses for any PTC. The model has been validated through comparison with the experimental results on the prototypes. Then it has been included in a custom-built simulation environment to predict yearly perfor- mances of a PTC field coupled with an industrial process heat demand. Energetic results are shown and final considerations are drawn for this application.
Pentacene-Based Organic Field-Effect Transistors: Analytical Model and Simula...IDES Editor
Organic Field-Effect Transistors, OFETs, attract
much interest recently and their proficiency and hence
applications are being enhanced increasingly. However, only
analytical model of old field-effect transistors, developed for
silicon-based transistors, and their relevant numerical
analyses have been used for such devices, so far. Increasing
precision of such models and numerical methods are essential
now in order to modify OFETs and propose more effective
models and methods. This study pegs at comparing current
analytical model, simulation methods and experiment data
and their fitness with each other. Certainly, four aspects of
results of three abovementioned approaches were examined
comparatively: sub-threshold slope, on-state drain current,
threshold voltage and carrier mobility. We embark to analyze
related experiment data of OFETs made by pentacene, as the
organic material, along with various organic gate insulators
including CyEP, PVP, PMMA, Parylene-C and Polyimide and
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Zipping Up Ni-Fe Hydroxide-Coated Hematite Nanowires
IEDM-2006_Abhijeet_Paul_new
1. 12/04/06 E. E. Dept, IIT Bombay 1
Comprehensive Simulation of
Programming, Erase & Retention in
Charge Trapping Flash Memory
A. Paul, Ch. Sridhar, S. Gedam and S. Mahapatra
Department of Electrical Engineering
IIT Bombay, India
2. 12/04/06 E. E. Dept, IIT Bombay 2
Outline
Introduction
Physics of operation
Simulation details & assumptions
Results
Conclusion & outlook
Impact of parameters
Prediction of experimental data
3. 12/04/06 E. E. Dept, IIT Bombay 3
Introduction
Charge Trap Flash to replace
FG for NAND applications
Charge storage in traps in
nitride
A simulator to understand
Physics of operation
Impact of physical parameters
Impact of trap parameters
Substrate
Tunnel oxide
Nitride
Blocking oxide
Gate
4. 12/04/06 E. E. Dept, IIT Bombay 4
Simulator Features
Self consistent, 1D simulator
Provides electric field, tunneling current, trapped and
free carriers in the stack with time
Study impact of physical and trap parameters
Stack design: Impact of trap profiles on P, E and R
Simulation of Program, Erase and Retention
Extraction of experimental trap parameters
5. 12/04/06 E. E. Dept, IIT Bombay 5
Outline
Introduction
Physics of operation
Simulation details & assumptions
Results
Conclusion & outlook
Impact of parameters
Prediction of experimental data
6. 12/04/06 E. E. Dept, IIT Bombay 6
Program
Electron tunneling from Si
to N, and N to poly-Si
Hole tunneling from poly-Si
to N, and N to Si
Trapping / detrapping of
electrons & holes in nitride
Poly-Si
Top Ox
Nitride
Bottom Ox
Si-substrate
VG>0
7. 12/04/06 E. E. Dept, IIT Bombay 7
Erase
Detrapping & tunneling
of electrons from N to Si
VG<0
Poly-Si
Top Ox
Nitride
Bottom Ox
Si-
substrate
Tunneling of electrons
from poly-Si to N, trapping
Detrapping & tunneling of
holes from N to poly-Si
Tunneling of holes from
Si to N, trapping
8. 12/04/06 E. E. Dept, IIT Bombay 8
Retention
Thermal (FP) emission
followed by tunneling to
Si and poly-Si
Poly-Si
VG=0
Top Ox
Bottom Ox
Si-
substrate
Nitride
Trap to band tunneling
Trap to trap hopping
Not solved for holes due to
negligible hole tunneling
and trapping
9. 12/04/06 E. E. Dept, IIT Bombay 9
Outline
Introduction
Physics of operation
Simulation details & assumptions
Results
Conclusion & outlook
Impact of parameters
Prediction of experimental data
10. 12/04/06 E. E. Dept, IIT Bombay 10
System Equations
Poisson Tunneling
(FN or DT)
Continuity
& SRH
Substrate
Tunnel oxide
Nitride
Blocking oxide
Gate
11. 12/04/06 E. E. Dept, IIT Bombay 11
Simulation Flow
User Input Deck:
Structure, doping
Mesh
Trap profile
Bias, Time
Parameter file:
Physical & trap
Poisson-Schrödinger
Potential
Transport & Trapping
Tunneling (FN / DT)
Continuity & SRH
VT shift
Time
Final
result
NO
YES
12. 12/04/06 E. E. Dept, IIT Bombay 12
Assumptions
Bottom & top oxides are pure tunneling barriers with
no traps. Traps are only in nitride, fixed in time.
Elastic tunneling through barriers, calculated using
thermalized carrier concentration.
Single energy level, non-interacting electron & hole traps.
No traps at substrate and Poly-Si interfaces.
Effective mass in nitride is a fitting parameter.
Free carrier density < trapped carrier density in nitride.
Drift as the only transport mechanism in nitride.
13. 12/04/06 E. E. Dept, IIT Bombay 13
Outline
Introduction
Physics of operation
Simulation details & assumptions
Results
Conclusion & outlook
Impact of parameters
Prediction of experimental data
14. 12/04/06 E. E. Dept, IIT Bombay 14
Simulated Electric Field for P & E
Program: Increase in
negative trap charge in N
Erase: Decrease in
negative trap charge in N
Reduction in E (bottom)
Reduction in E (top)
Increase in E (bottom)
Increase in E (top)
15. 12/04/06 E. E. Dept, IIT Bombay 15
Impact of Effective Mass
Higher m*: lower JTUN
Higher m* (tunnel-oxide):
lower VT shift in P
Higher m* (top-oxide):
faster VT shift in E
(reduced back injection
through top-oxide)
e,ox
T
e,ox
T
e,ox
T
16. 12/04/06 E. E. Dept, IIT Bombay 16
Impact of Attempt to Escape Frequency
Higher :
Faster de-trapping
Lower VT shift in P
Higher VT shift in E
17. 12/04/06 E. E. Dept, IIT Bombay 17
Impact of Capture Cross-section
Higher : Faster trapping
Higher VT shift in P
Lower VT shift in E
18. 12/04/06 E. E. Dept, IIT Bombay 18
Impact of electron trap depth
Deeper traps: More
electron capture
Increase in trap depth
Increases ∆Vt during P
Increase in trap depth
Decreases ∆Vt during E
19. 12/04/06 E. E. Dept, IIT Bombay 19
Impact of Trap Profile – Program
Lower VT shift for lower trap density near tunnel oxide
20. 12/04/06 E. E. Dept, IIT Bombay 20
Impact of Trap Profile – Erase
Slower erase for lower trap density near tunnel oxide
21. 12/04/06 E. E. Dept, IIT Bombay 21
Prediction of Experimental P / E Results
SONOS: n+ poly-Si / 5.8nm SiO2 / 8nm Si3N4 / 5nm SiO2 / p-Si
22. 12/04/06 E. E. Dept, IIT Bombay 22
Prediction of Experimental P / E Results
SONOS: n+ poly-Si / 5.8nm SiO2 / 6nm Si3N4 / 5nm SiO2 / p-Si
During Erase devices
were pre-programmed
for 10s at Vg =11V.
23. 12/04/06 E. E. Dept, IIT Bombay 23
Prediction of Experimental R Results
SONOS: n+ poly-Si / 5.8nm SiO2 / 8nm Si3N4 / 5nm SiO2 / p-Si
Experimental data
is for pre-cycling
retention.
24. 12/04/06 E. E. Dept, IIT Bombay 24
Extracted Trap Distribution
All other parameters
are identical for these
devices
Higher trap density
near interfaces than
center
Larger trap density
at top interface
25. 12/04/06 E. E. Dept, IIT Bombay 25
Prediction of TANOS Result – Program
OT/N/OB = 15nm / 6.5nm / 4nm
Shin, IEDM 05
simulated
20us
~4V
~4
V
20us
26. 12/04/06 E. E. Dept, IIT Bombay 26
Prediction of TANOS Result – Erase
OT/N/OB = 15nm / 6.5nm / 4nm
Shin, IEDM 05
simulated
~4V
2 ms
~4V
2 ms
27. 12/04/06 E. E. Dept, IIT Bombay 27
Extracted Trap Distribution – TANOS
Higher trap density
near interface than
center
Larger density at top
interface
Similar trap profile for
SONOS and TANOS
28. 12/04/06 E. E. Dept, IIT Bombay 28
Outline
Introduction
Physics of operation
Simulation details & assumptions
Results
Conclusion & outlook
Impact of parameters
Prediction of experimental data
29. 12/04/06 E. E. Dept, IIT Bombay 29
Conclusion & Outlook
Self consistent, 1D simulator for P, E and R
Solves Poisson, Tunneling, Continuity & SRH
Good prediction of experimental results (SONOS &
TANOS) over wide experimental conditions
Provides physical and trap parameters, trap profiles
Useful tool to understand device physics, stack design,
parameter extraction
Acknowledgement:
IIT Bombay: J. Vasi, D. K. Sharma, N. Jain
Renesas Technologies (Japan): E. Murakami, K. Kubota, S. Kamohara