Register now for the Stanford University Photonics Retreat!

The Stanford Optical Society and the
Stanford Photonics Research Center cordially invite you to the

 

All Stanford students, post-docs, and faculty interested in optics and photonics are invited to gather together for a weekend retreat near beautiful Point Reyes!

For more information: http://supr.stanford.edu

Register Online: 12:00 PM Tuesday, February 22 - 11:59 PM Friday, March 4

 

Cost for students & post-docs*:

$60 (OSA or SPIE Member) or $150 (non-member) 
*Interested faculty: please contact us at Stanford-photons@stanford.edu

Registration includes 2 nights shared lodging at the Marconi Conference Center, all meals, and transportation. Sign up or renew your OSA or SPIE membership for large savings!

Limited space is available and we expect that registration will close before the deadline, so sign up early.  Late registrants will be put on a waiting list.

 For more info, see general information and look at pictures from last year!

 

Corporate Partners

 

[Reminder] University PhD Dissertation Defense of Mihir P. Tendulkar CISX-101 Monday 10am

----- Forwarded Message -----
From: "Claire Nicholas" <claireni@stanford.edu>
Cc: apgradstudents@lists.stanford.edu, apfaculty@lists.stanford.edu
Sent: Friday, February 25, 2011 8:37:05 AM
Subject: RE: University PhD Dissertation Defense of Mihir P.Tendulkar

RE: University PhD Dissertation Defense of Mihir P.Tendul
REMINDER

Department of Applied Physics
University PhD Dissertation Defense

Impact of Hydrogen on the Forming and Switching of RF-Sputtered Pr(0.7)Ca(0.3)MnO(3) Thin Films for Resistance Change Memory

Mihir Prakash Tendulkar
Research Advisor: Professor Yoshio Nishi

February 28, 2011 @10:00 a.m.
(Refreshments served at 9:45 a.m.)

Location: Allen Building, (CIS-X formerly), Room 101

ABSTRACT
The continued scaling of NAND Flash memory technology is facing significant physical, electrical, and reliability challenges. Beyond the 16nm technology node, the issues associated with these challenges may offset or even counteract the benefits of increased density. An increased appetite for high-capacity memory devices motivates the need to investigate new functional devices and materials for next-generation memory technology. One promising solution is Resistance-change Random Access Memory (RRAM), which offers the advantages of low cost, simple device structure, low power write and erase, high-speed switching, and integration into monolithic memory.

Despite these advantages, some barriers must be overcome. Resistance-change films typically require "electroforming" - a one-time voltage application that induces a change in the film conductivity - before resistance switching can be accessed. Moreover, RRAM devices often display great variation, which partly arises from the lack of thorough understanding of the resistance switching mechanism. Filament formation through oxygen vacancies is typically cited as the underlying mechanism; however, the finer details remain hotly contested. Understanding these details may provide insight into overcoming the aforementioned hurdles.

In this work, hydrogen contamination of RF-sputtered Pr(0.7)Ca(0.3)MnO(3) (PCMO) thin films is investigated as a reason for large device-to-device variation. Significant hydrogen is shown to enter the films during standard deposition and processing steps. Its effects on electroforming, switching, dielectric loss, and optical absorption are presented. These measurements are considered together to devise a comprehensive model for hydrogen-assisted electroforming and switching in PCMO.

--
--++**==--++**==--++**==--++**==--++**==--++**==--++**==
apgradstudents mailing list
apgradstudents@lists.stanford.edu
https://mailman.stanford.edu/mailman/listinfo/apgradstudents

--
Mihir Tendulkar
Applied Physics PhD Candidate
Nishi Group, Stanford University

Reminder: EE PhD Oral Examination: Dany-Sebastien Ly-Gagnon, Tuesday, March 1st, 9:45am

Stanford University PhD Dissertation Defense - Department of Electrical Engineering

Integrated plasmonic waveguide photodetectors for optical interconnection of silicon chips

Speaker: Dany-Sebastien Ly-Gagnon
Research Advisor: Professor David A.B. Miller
Date: Tuesday, 1 March 2011
Time: 9:45 a.m. (Refreshments at 9:30 a.m.)
Location: Nano Building, Room 232

ABSTRACT

To keep pace with the scaling of semiconductor technology, the amount of energy required to transmit one bit of information needs to be drastically reduced. Optical interconnects may become a key technology in enabling high bandwidth interconnections, provided that its components operate at sufficiently low energies per bit. At the receiver, the capacitance of the photodetector limits the speed and power consumption that can be achieved. Lower capacitance can be achieved by reducing the physical size of the photodetector to nanoscale volumes, an order of magnitude smaller than the optical wavelength. Metallic nanostructures can be used to bridge this size mismatch between the optical mode and the optoelectronic device, enhancing interaction between the optical signal and the photodetector. Plasmonic waveguides provide an efficient way of routing optical signals with deep subwavelength mode dimensions and integrate well with nanoscale photodetectors, providing a route towards highly integrated low capacitance detectors for optical interconnects.

In this talk, I will present our work on integrated plasmonic waveguide photodetectors. We developed a model based on the modal characteristic impedance that allows us to calculate transmission and reflection in deep subwavelength metal slot waveguides. We illustrate how this approach can be used to design an asymmetric Fabry-Perot photodetector with high efficiency despite metallic losses. We experimentally demonstrate propagation of highly confined optical modes at near-infrared wavelength in two-conductor plasmonic waveguides and its detection with an on-chip integrated photodetector. Our results show that these optical modes can propagate several optical wavelengths and make it through 90 degree bends, while the strong optical confinement allows the signal to be detected in photodetectors with limited footprint.

chemistry of sih4

Hello, I wonder if you can direct me to the right people/literature
about the gas phase chemistry of silane(SiH4). I only know that it is
used for depositing Si at high temperature. But at condensed phase, the
compound shows very rich chemistry.

Best,
Shibing

--
Shibing Wang
Ph.D. Candidate
Department of Applied Physics
Stanford University

348 Via Pueblo Mall
Department of Applied Physics
Stanford, CA, 94305-4090
Tel: 650 862 3001

VACUUM TRAINING SEMINAR at Stanford University, March 9th

All,

Please respond to Shawn Jones if you plan on attending.

Regards,
SNF Sraff

>From: Shawn Jones <shawnj@lesker.com>
>
>Good afternoon,
>The Stanford Nanofabrication Facility, the Stanford NanoCenter and
>the Kurt J Lesker Company invite you to attend our upcoming Vacuum
>Training Seminar on Wednesday, March 9th. We will feature two
>different sessions, General Vacuum Technology in the morning
>followed by PVD Processes in the afternoon. The two sessions will be
>given by Kurt J. Lesker's Mike McKeown with a 1 hour lunch break in
>between. The entire event is free but due to space limitations we
>ask that you RSVP as acceptance will be on a first come, first served basis.
>Please RSVP to Shawn Jones
><mailto:shawnj@lesker.com>shawnj@lesker.com or contact me directly
>at (209) 401-6453 with any questions/comments. We will send
>additional parking information to all of those who RSVP.
>
>Shawn U. Jones | Regional Manager | Kurt J. Lesker Company | O:
>925.449.0104 | C: 209.401.6453 | <http://www.lesker.com>www.lesker.com
>If this email is transmitted to you in error, please notify me, and
>then delete this email and all copies. If this email is sent for
>legal or business purposes, (a) this email and its content or
>attachments may include confidential and/or proprietary information
>of Kurt J. Lesker Company, in which case all rights to that
>information are reserved by the Company, and (b) your right and
>authorization to retain, and use, this information is limited to the
>purpose(s) expressly stated in, or reasonably implied by, this
>email. Any questions should be directed to me. Thank you.
>

PhD defense, Nazanin Davani (March 7, Monday, 11 am, Packard 202)

Electrical and Optical Characterization of Molecular Junctions

Nazanin Davani

Stanford University PhD Dissertation Defense-Department of Chemical Engineering

Research Advisor: Professor Nicholas A. Melosh

 

March 7th (Monday), 2011 @ 11 am

(Refreshments served at 10:45 am)

 

Location: Packard 202

http://ee.stanford.edu/directions.php?bld=packard

Electronic transport through molecules has been intensively studied in recent years, due to scientific interest in fundamental questions about charge transport and the technological promise of nanoscale circuitry. A variety of experimental platforms have been developed to electronically probe molecular junctions. However, it remains challenging to fabricate reliable electronic contacts to molecules, and the vast majority of molecular electronic architectures are not amenable to standard characterization techniques, such as optical spectroscopy. Interesting phenomena like switching and rectification are observed in molecular junctions. However, due to limited quantitative information about the junction, the mechanism remains unknown and many fundamental questions about electronic transport remain unanswered.

The first part of the presentation will introduce the fabrication of Metal-Insulator-Metal (MIM) cross bar junctions using soft deposition technique. In this method, we softly deposit the premade metal contacts that are being supported with a polymer backing layer onto the organic layer. Using this method, we can efficiently fabricate large area, non-shorting devices, which are required for optical characterization of the molecular junctions.

Having established a means of fabricating reliable molecular devices, we have investigated the switching mechanism in molecular junctions based on n-type semiconductor Perylene tetracarboxylic diimide (TE-PTCDI) molecules. Using Surface Plasmon Resonance Spectroscopy (SPRS) we have been able to perform simultaneous optical-electrical measurements to study the molecular behavior quantitatively. Using in-situ optical spectroscopy on active molecular junctions, we find that only a small fraction of the molecules are actually switching in the junction. Finally, I present the results of our studies on the molecular rectification in C60-diamondoid hybrid molecules in large area junctions, as well as in smaller ensemble of molecules. The statistical studies along with a theoretical model show the origin of rectification in such molecular devices.

 

Lost USB Stick (Kingston Memory Stick) last seen in the Cad Room #151

Dear All,

 

This morning I had a hand written note on my desk from Edward from ERA 1 Consulting.  He was in a few evenings ago and left his (Kingston Memory Stick) USB stick in a computer in the Cad Room #151.  If you picked it up by mistake or know where it might be, please let me know or send Ed a note at era1consulting@yahoo.com .

 

Thank you for your time in this matter.

 

Sincerely,

 

Maureen

 

 

 

Maureen Baran

Stanford Nanofabrication Facility

Lab Services Administrator

mbaran@stanford.edu

650-725-3664

 

Re: Comment p5000etch SNF 2011-02-22 00:35:37: re: process b chamber stopped

Archived

Re: Problem p5000etch SNF 2011-02-24 06:56:53: Ch.B error

The turbo pump was off. Turned the pump back on. Ran 8 wafers with no problems.

Found Umbrella in the Kitchen Area

A concerned dweller of the Allen building found an umbrella in the Kitchen area this morning.  If it’s yours please come to my cubicle #41 and claim it.

 

Maureen

 

Maureen Baran

Stanford Nanofabrication Facility

Lab Services Administrator

mbaran@stanford.edu

650-725-3664

 

Problem p5000etch SNF 2011-02-24 06:56:53: Ch.B error

Same error as previously observed in Ch.B. Pressure is high and there are some gas flows before process even starts.

EE PhD Oral Examination: Dany-Sebastien Ly-Gagnon, Tuesday, March 1st, 9:45am

Stanford University PhD Dissertation Defense - Department of Electrical Engineering

Integrated plasmonic waveguide photodetectors for optical interconnection of silicon chips

Speaker: Dany-Sebastien Ly-Gagnon
Research Advisor: Professor David A.B. Miller
Date: Tuesday, 1 March 2011
Time: 9:45 a.m. (Refreshments at 9:30 a.m.)
Location: Nano Building, Room 232

ABSTRACT

To keep pace with the scaling of semiconductor technology, the amount of energy required to transmit one bit of information needs to be drastically reduced. Optical interconnects may become a key technology in enabling high bandwidth interconnections, provided that its components operate at sufficiently low energies per bit. At the receiver, the capacitance of the photodetector limits the speed and power consumption that can be achieved. Lower capacitance can be achieved by reducing the physical size of the photodetector to nanoscale volumes, an order of magnitude smaller than the optical wavelength. Metallic nanostructures can be used to bridge this size mismatch between the optical mode and the optoelectronic device, enhancing interaction between the optical signal and the photodetector. Plasmonic waveguides provide an efficient way of routing optical signals with deep subwavelength mode dimensions and integrate well with nanoscale photodetectors, providing a route towards highly integrated low capacitance detectors for optical interconnects.

In this talk, I will present our work on integrated plasmonic waveguide photodetectors. We developed a model based on the modal characteristic impedance that allows us to calculate transmission and reflection in deep subwavelength metal slot waveguides. We illustrate how this approach can be used to design an asymmetric Fabry-Perot photodetector with high efficiency despite metallic losses. We experimentally demonstrate propagation of highly confined optical modes at near-infrared wavelength in two-conductor plasmonic waveguides and its detection with an on-chip integrated photodetector. Our results show that these optical modes can propagate several optical wavelengths and make it through 90 degree bends, while the strong optical confinement allows the signal to be detected in photodetectors with limited footprint.

Sputtering facility

Dear members:

I’m looking for a facility that have sputter tools available which operates with 1 inch targets (like Metallica).

Thanks,
Rainer Fasching

Re: Problem p5000etch SNF 2011-02-22 00:33:36: chamber b process stopped

[reminder] EE PhD Oral Examination Kyun-Hoae Koo, Wednesday, February 23, 2011, 2:00pm

Stanford University Ph.D. Dissertation Defense - Department of Electrical Engineering

 

Title: " Performance Comparison Study of Future On-Chip Interconnects for High Performance VLSI Applications"

 

Speaker: Kyung-Hoae Koo

Advisor: Krishna C. Saraswat

Date: Wednesday, February 23rd, 2011

Time: 2:00pm (refreshments served at 1:45 pm)

Location: CISX-101  Auditorium

 

Abstract :

-----------------------------------------------------------------------------------------------------------------------------------

Optical interconnects and carbon nanotubes (CNTs) present promising options for replacing the existing Cu-based global/semiglobal (optics and CNT) and local (CNT) wires. This work quantifies the performance of these novel interconnects and compare it with Cu/low-κ wires for future high-performance integrated circuits. For a local wire, a CNT bundle exhibits a smaller latency than Cu for a given geometry. In addition, by leveraging the superior electromigration properties of CNT and optimizing its geometry, the latency advantage can be further amplified. For semiglobal and global wires, we compare both optical and CNT options with Cu in terms of latency, energy efficiency/power dissipation, and bandwidth density. The new circuit scheme, i.e. “capacitively driven low-swing interconnect (CDLSI),” has the potential to effect a significant energy saving and latency reduction. This work also presents an accurate analytical optimization model for the CDLSI wire scheme. It is found that the CDLSI circuit scheme outperforms the conventional interconnects in latency and energy per bit for a lower bandwidth requirement, whereas these advantages degrade for higher bandwidth requirements.

 

 

Re: Good etch recipe for Ta?

Mihir,

Ta can be dry etched in fluorine base chemistries. So the poly-si etch recipe (F124(C2ClF5)/ SF6) in the Dryteks should work. CF4 should also work. In the MRC, again I would try the poly etch ( F124/SF6).

Jim

James (Jim) P. McVittie, Ph.D. Sr. Research Scientist
Paul G. Allen Building Electrical Engineering
Stanford Nanofabrication Facility jmcvittie@stanford.edu
Stanford University Office: (650) 725-3640
Rm. 336X, 330 Serra Mall Lab: (650) 721-6834
Stanford, CA 94305-4075 Fax: (650) 723-4659

----- Original Message -----
From: "Mihir Tendulkar" <mihirt@stanford.edu>
To: "labmembers" <labmembers@snf.stanford.edu>
Sent: Monday, February 21, 2011 11:15:39 PM
Subject: Good etch recipe for Ta?

Hi labmembers,

I'm using a structure with a Ta top layer. I've patterned it with SPR-955 and attempted to dry etch it using the Ar milling recipe developed on the MRC.

The milling is mostly trashing my resist instead of etching the Ta. I suspect there is a protective TaOx layer inhibiting the etch. Has anyone found a reactive etch that works for this metal?

--
Mihir Tendulkar
Applied Physics PhD Candidate
Nishi Group, Stanford University

Dynamic Characterization of MEMS Using Laser Vibrometry, TODAY @ 2PM

On Tue, Feb 15, 2011 at 9:21 AM, Scott Lee <wslee@stanford.edu> wrote:

Hi all,

Next week, Eric Lawrence of Polytec will be demonstrating their latest laser vibrometry tools.  If you have samples that you would like to characterize, let me know and we may be able to arrange it.

Thanks,

Scott

--------------------------------------------------------------------------------------------------------------------------

Technical Presentation:  Dynamic Characterization of MEMS using Laser Vibrometry

When:  Tuesday February 22, 2:00 PM

Where:  Room 338X, PAUL G. ALLEN BUILDING (04-050), 420 VIA PALOU MALL

 

Polytec presents technology for dynamic characterization of MEMS.  OurMicro System Analyzer (MSA-500) combines powerful tools for analysis and visualization of structural vibrations of MEMS.  The MSA-500 features laser vibrometry for measurement of out-of-plane motion with resolution down to picometers and bandwidth out to MHz.  Scanning measurements provide full-field mapping and 3D visualization of deflection shapes. The system also includes Strobe Video Microscopy for planar motion and White Light Interferometer for static topography measurements.  Our latest capabilities include our Ultra High Frequency (UHF-120) Vibrometer featuring 1.2 GHz frequency bandwidth.

 

This technology is used throughout the MEMS research community.  We present several characterization studies where our MSA has been instrumental in research and development of MEMS. 

 

Our engineers will present new advances in our measurement technology and discuss potential MEMS applications you may have. 

 

More information at:  http://www.polytec.com/int/applications/micro-nano-technology/

 

Eric Lawrence

Northwest Territory Manager

 

Polytec Inc.

Irvine Technology Center

16400 Bake Parkway

Irvine, CA 92618

 

Cell:  (714) 200-4019

 

Comment p5000etch SNF 2011-02-22 00:35:37: re: process b chamber stopped

fixed using "end current recipe" (even though there was nothing running?)

Problem p5000etch SNF 2011-02-22 00:33:36: chamber b process stopped

even though all my wafers successfully unloaded... not sure what happened.

Applied Physics PhD Oral Examination: Mihir Tendulkar, Monday, February 28, 2011, 10am

Stanford University Ph.D. Dissertation Defense - Department of Applied Physics

Title: "Impact of hydrogen on the forming and switching of RF-sputtered Pr(0.7)Ca(0.3)MnO(3) thin films for resistance change memory"

Speaker: Mihir Prakash Tendulkar
Research Advisor: Prof. Yoshio Nishi

Date: Monday, Feb 28th, 2011
Time: 10:00 am (Refreshments served at 9:45 am)
Location: CISX-101 (Auditorium)

Abstract:

The continued scaling of NAND Flash memory technology is facing significant physical, electrical, and reliability challenges. Beyond the 16nm technology node, the issues associated with these challenges may offset or even counteract the benefits of increased density. An increased appetite for high-capacity memory devices motivates the need to investigate new functional devices and materials for next-generation memory technology. One promising solution is Resistance-change Random Access Memory (RRAM), which offers the advantages of low cost, simple device structure, low power write and erase, high-speed switching, and integration into monolithic memory.

Despite these advantages, some barriers must be overcome. Resistance-change films typically require "electroforming" – a one-time voltage application that induces a change in the film conductivity – before resistance switching can be accessed. Moreover, RRAM devices often display great variation, which partly arises from the lack of thorough understanding of the resistance switching mechanism. Filament formation through oxygen vacancies is typically cited as the underlying mechanism; however, the finer details remain hotly contested. Understanding these details may provide insight into overcoming the aforementioned hurdles.

In this work, hydrogen contamination of RF-sputtered Pr(0.7)Ca(0.3)MnO(3) (PCMO) thin films is investigated as a reason for large device-to-device variation. Significant hydrogen is shown to enter the films during standard deposition and processing steps. Its effects on electroforming, switching, dielectric loss, and optical absorption are presented. These measurements are considered together to devise a comprehensive model for hydrogen-assisted electroforming and switching in PCMO.

--
Mihir Tendulkar
Applied Physics PhD Candidate
Nishi Group, Stanford University

Good etch recipe for Ta?

Hi labmembers,

I'm using a structure with a Ta top layer. I've patterned it with SPR-955 and attempted to dry etch it using the Ar milling recipe developed on the MRC.

The milling is mostly trashing my resist instead of etching the Ta. I suspect there is a protective TaOx layer inhibiting the etch. Has anyone found a reactive etch that works for this metal?

--
Mihir Tendulkar
Applied Physics PhD Candidate
Nishi Group, Stanford University

Pt dryetch

Hi all,

 

Does anybody have experience to dryetch Pt? 

 

Thank you in advance,

 

Jihwan



--
Jihwan An
Ph.D. Student
Rapid Prototyping Laboratory
Department of Mechanical Engineering
Stanford University, CA

cell : 650-862-0414
e-mail: jihwanan@stanford.edu
           gojh82@gmail.com

Re: XSEM sample prep...

There's a crystal shop in the nano building...they might be able to help?

On Fri, Feb 18, 2011 at 5:10 PM, Robert Huang <roberth@quswami.com> wrote:
> Sorry for the additional mass-mailing, but I should have been a little more
> specific in my original email.  I'm looking to do polish sample prep.  We've
> been doing cleaves so far, but we'd like to avoid any possible
> damage/artifacts from the cleaving itself.
>
>
>
> Robert
>
>
>
> From: Robert Huang [mailto:roberth@quswami.com]
> Sent: Friday, February 18, 2011 2:26 PM
> To: labmembers@snf.stanford.edu
> Cc: Arash Hazeghi
> Subject: XSEM sample prep...
>
>
>
> Fellow labmembers,
>
>
>
> Does anyone have information on where I can do cross-section SEM sample prep
> myself?  I'm hoping there's equipment/facilities somewhere on campus.
>
>
>
> Thanks.
>
>
>
> Robert

RE: XSEM sample prep...

Sorry for the additional mass-mailing, but I should have been a little more specific in my original email.  I’m looking to do polish sample prep.  We’ve been doing cleaves so far, but we’d like to avoid any possible damage/artifacts from the cleaving itself.

 

Robert

 

From: Robert Huang [mailto:roberth@quswami.com]
Sent: Friday, February 18, 2011 2:26 PM
To: labmembers@snf.stanford.edu
Cc: Arash Hazeghi
Subject: XSEM sample prep...

 

Fellow labmembers,

 

Does anyone have information on where I can do cross-section SEM sample prep myself?  I’m hoping there’s equipment/facilities somewhere on campus.

 

Thanks.

 

Robert

XSEM sample prep...

Fellow labmembers,

 

Does anyone have information on where I can do cross-section SEM sample prep myself?  I’m hoping there’s equipment/facilities somewhere on campus.

 

Thanks.

 

Robert

Comment p5000etch SNF 2011-02-18 14:23:05: Ch B and Ch C quals

Here are the Feb quals for chambers B and C;
Chamber B- CH.B OXIDE, 60s
Thermal Ox = 3559A/min
PR = 1728A/min
Si nitride = 2994A/min
Poly Si = 1079A/min
Sel PR = 2.1
Sel SiN = 1.2
Sel Poly = 3.3
Chamber C- CH.C POLY ETCH, 60s
Poly Si = 4740A/min
PR = 597A/min
Thermal ox = 442A/min
Sel PR = 7.9
Sel Th ox = 10.7
These results are also posted on the wiki.

Ag evap

Hi all,

Does anyone know where I can get Ag deposited on six inch wafers? I need 2 microns, so I'm looking for e-beam or regular evaporation?

Jeremy Theil

Sent from my iPhone

Polyimide processing

Dear labmembers,

Does anyone have experience with using polyimide from HDmicrosystems, specifically the PI-2600s series?

Thanks!

Ben

PDMS chip bonding

Hi all,

 

I need to make some dummy PDMS chips and test their bonding to my glass substrate with structures on it. Does any one have experience with the PDMS bonding? Also Does anyone have some silicone elastomer and curing agent that I can use to make some chips for a test? Thanks a lot!

 

Yuxin

Re: Comment p5000etch SNF 2011-02-15 14:57:10: Ch.C is down for loading problem

Slit door was not opening in time. Adjusted the pneumatic cylinder metering valve. Cycled 20 wafers through the chamber with no problems.

Re: Comment p5000etch SNF 2011-02-01 14:40:12: Replaced HBR cylinder

Slit door was not opening in time. Adjusted the pneumatic cylinder metering valve. Cycled 20 wafers through the chamber with no problems.

Re: Problem p5000etch SNF 2011-02-15 02:23:16: pump in chamber C problem?

Slit door was not opening in time. Adjusted the pneumatic cylinder metering valve. Cycled 20 wafers through the chamber with no problems.

Re: Problem p5000etch SNF 2011-02-15 01:33:11: waiting for blade in for too long in chamber C

Slit door was not opening in time. Adjusted the pneumatic cylinder metering valve. Cycled 20 wafers through the chamber with no problems.

EE PhD Oral Examination Kyun-Hoae Koo, Wednesday, February 23, 2011, 2:00pm

Stanford University Ph.D. Dissertation Defense - Department of Electrical Engineering

 

Title: " Performance Comparison Study of Future On-Chip Interconnects for High Performance VLSI Applications"

 

Speaker: Kyung-Hoae Koo

Advisor: Krishna C. Saraswat

Date: Wednesday, February 23rd, 2011

Time: 2:00pm (refreshments served at 1:45 pm)

Location: CISX-101  Auditorium

 

Abstract :

-----------------------------------------------------------------------------------------------------------------------------------

Optical interconnects and carbon nanotubes (CNTs) present promising options for replacing the existing Cu-based global/semiglobal (optics and CNT) and local (CNT) wires. This work quantifies the performance of these novel interconnects and compare it with Cu/low-κ wires for future high-performance integrated circuits. For a local wire, a CNT bundle exhibits a smaller latency than Cu for a given geometry. In addition, by leveraging the superior electromigration properties of CNT and optimizing its geometry, the latency advantage can be further amplified. For semiglobal and global wires, we compare both optical and CNT options with Cu in terms of latency, energy efficiency/power dissipation, and bandwidth density. The new circuit scheme, i.e. “capacitively driven low-swing interconnect (CDLSI),” has the potential to effect a significant energy saving and latency reduction. This work also presents an accurate analytical optimization model for the CDLSI wire scheme. It is found that the CDLSI circuit scheme outperforms the conventional interconnects in latency and energy per bit for a lower bandwidth requirement, whereas these advantages degrade for higher bandwidth requirements.

 

 

Seminar at 4:00, Allen 101X, Maryam Ziaei-Moayyed

see you there --

Comment p5000etch SNF 2011-02-15 14:57:10: Ch.C is down for loading problem

Recovered the user's wafer.
The chamber slit valve open position is not being sensed. Need to troubleshoot.

Dynamic Characterization of MEMS Using Laser Vibrometry, Feb. 22 @ 2PM

Hi all,

Next week, Eric Lawrence of Polytec will be demonstrating their latest laser vibrometry tools.  If you have samples that you would like to characterize, let me know and we may be able to arrange it.

Thanks,

Scott

--------------------------------------------------------------------------------------------------------------------------

Technical Presentation:  Dynamic Characterization of MEMS using Laser Vibrometry

When:  Tuesday February 22, 2:00 PM

Where:  Room 338X, PAUL G. ALLEN BUILDING (04-050), 420 VIA PALOU MALL

 

Polytec presents technology for dynamic characterization of MEMS.  OurMicro System Analyzer (MSA-500) combines powerful tools for analysis and visualization of structural vibrations of MEMS.  The MSA-500 features laser vibrometry for measurement of out-of-plane motion with resolution down to picometers and bandwidth out to MHz.  Scanning measurements provide full-field mapping and 3D visualization of deflection shapes. The system also includes Strobe Video Microscopy for planar motion and White Light Interferometer for static topography measurements.  Our latest capabilities include our Ultra High Frequency (UHF-120) Vibrometer featuring 1.2 GHz frequency bandwidth.

 

This technology is used throughout the MEMS research community.  We present several characterization studies where our MSA has been instrumental in research and development of MEMS. 

 

Our engineers will present new advances in our measurement technology and discuss potential MEMS applications you may have. 

 

More information at:  http://www.polytec.com/int/applications/micro-nano-technology/

 

Eric Lawrence

Northwest Territory Manager

 

Polytec Inc.

Irvine Technology Center

16400 Bake Parkway

Irvine, CA 92618

 

Cell:  (714) 200-4019

 

Problem p5000etch SNF 2011-02-15 02:23:16: pump in chamber C problem?

I managed to get to the manual mode, however, i could not get the wafer out of the chamber C in manual mode. It seems that turbo pump in chamber c is not working well to get to the vacuum level.

Problem p5000etch SNF 2011-02-15 01:33:11: waiting for blade in for too long in chamber C

wafer was lifted up, everything seems to be okay but the blade was not getting in to the chamber. Cannot abort to get to the manual mode.

RSoft's BeamPROP software

Hi everyone,

We have recently developed a series of simulations using RSoft's BeamPROP software (which is primarily used for using the beam propagation method to simulate waveguide devices), but have reached the end of our trial version and are considering purchasing a license. I wanted to check to see if anyone in the SNF community has a copy of this software that they would be willing to let me occasionally use, or if anyone is interested in sharing the cost of a license with us.

Thanks,
Stephanie Claussen

Re: Problem p5000etch SNF 2011-01-19 16:54:10: Limits on HBr Usage

OK to use HBr any time now.

New Course Announcement, E204: Research Ethics for Engineers & Scientists

Dear labmembers --

Have you ever wondered:

- How is authorship on a paper decided? Who gets to be first author?
What are the responsibilities of a contributors to jointly authored paper?
- Who should be included as an inventor on a patent?
- Is it OK to omit "bad" data points from an analysis?
- What can and should you do if you suspect fraudulent data?
- How should peer review be handled? How is it actually done?
- Are you responsible for anticipating the ways, good and bad, that your
research might be used? What are a researcher's specific
responsibilities to society?
- What are the responsibilities of mentors and mentees?
- What kinds of conflicts of interest are important to avoid?

Explore these issues and more, in E204, Research Ethics for Engineers
and Scientists, a new course that examines the practical aspects of
ethics for researchers with lectures, discussions, guest speakers, and
real case studies. This course is 1-2 units and will be held Spring
term, on Wednesdays, 4:15-6 pm, in Allen 101. The course instructor is
Prof. Robert McGinn, Director of the Program in Science, Technology &
Society. For more information, see the Bulletin or contact Prof. McGinn,
Mary Tang, or Mike Deal.

For students supported by NSF fellowships, this course satisfies the NSF
requirement for "Training in the responsible and ethical conduct of
research."

(Reminder) PhD Oral Examination, Cheng-Chieh Chao, TODAY, Monday, Feb 14, 2011, 3:15 pm, McCullough 335

Stanford University Oral Examination

Cheng-Chieh Chao
Department of Mechanical Engineering
Advisor: Prof. Fritz B. Prinz

Monday Feb 14th, 3:15 pm (refreshments at 3 pm)
McCullough Building, Room 335

Atomic layer deposition for solid oxide fuel cells

Solid oxide fuel cells (SOFCs) are attractive for their high energy conversion efficiency in the usage of fuels ranging from hydrogen to hydrocarbons. Nevertheless, they have limited applications because this high efficiency cannot be achieved without high operating temperatures, which pose significant engineering challenges, diminishing the SOFCs practicality for applications such as portable power sources. Lowering the operating temperatures of SOFCs may improve thermal stability and offer shorter start-up times, which in turn might broaden their use as auxiliary power units for automobiles. Although many studies have aimed at lowering the SOFC operating temperatures, this temperature reduction has been inevitably accompanied by a decrease in the electrochemical performance, which is contributed by a larger activation loss and ohmic loss. These two losses are related to sluggish reaction kinetics at the electrode/electrolyte interface (interfacial resistance) and poor ionic conductivity in the electrolyte (electrolyte resistance) at reduced temperatures. In this talk, I will present the approaches to reduce both losses with the help of atomic layer deposition (ALD).

In the first approach, ALD was used to fine-tune the electrolyte surface properties, which improved the reaction kinetics at the electrode/electrolyte interface. In the second approach, the nucleation of ALD platinum catalyst was investigated by TEM to improve the catalyst nanostructure, which reduced the activation loss during fuel cell operation. In the third approach, ALD was used to fabricate an ultra-thin SOFC electrolyte, which reduced the ohmic loss during fuel cell operation. In the last approach, by combining the nanosphere lithography (NSL) and ALD process, a corrugated thin-film electrolyte was fabricated to provide a larger area for interfacial reactions. By reducing activation loss and ohmic loss with these approaches, the electrochemical performance of SOFC was improved at low temperatures.

Re: Ion implantation company for heated non-standard ion implants

CORE Systems is the place to go.
1050 Kifer Road, Sunnyvale, CA 94086 (408) 328-1340
Ask for Chuck.
Good luck,
Betty

----- Original Message -----
From: "Jenny Hu" <jennyhu@stanford.edu>
To: "labmembers" <labmembers@snf.stanford.edu>
Sent: Sunday, February 13, 2011 3:43:00 AM
Subject: Ion implantation company for heated non-standard ion implants

Hi Labmembers,

Does anyone know of any reliable ion implantation companies that can do a heated (~200oC) implant of non-standard ions such as Si, S, and Te? I know Innovion and Coresystems are very good implant companies, however, for non-standard ions they add a $1000 set-up in addition to their $500/implant fee. In the past I have used Luxience for affordable implantation of these elements, but they do not offer heated implants.

Thank you very much in advance for your help.

Sincerely,
Jenny

Ion implantation company for heated non-standard ion implants

Hi Labmembers,

Does anyone know of any reliable ion implantation companies that can do a heated (~200oC) implant of non-standard ions such as Si, S, and Te? I know Innovion and Coresystems are very good implant companies, however, for non-standard ions they add a $1000 set-up in addition to their $500/implant fee. In the past I have used Luxience for affordable implantation of these elements, but they do not offer heated implants.

Thank you very much in advance for your help.

Sincerely,
Jenny

Re: Problem p5000etch SNF 2011-02-10 02:57:21: bonded piece detached from the wafer and lost in Chamber C

Recovered sample chip and wet cleaned the chamber..

Seminar Tuesday February 15, 4-5pm in Allen 101x: Maryam Ziaei-Moayyed of Sandia National Laboratories

Hello all,

Maryam Ziaei-Moayyed (Stanford PhD 2009) of the Advanced MEMS Department at Sandia National Labs will be delivering a seminar on Tuesday the 15th in Allen 101x at 4pm.

The talk is entitled "Micro and Nanoscale Acoustic Devices for Communication, Sensing, and Energy" and the full abstract is attached.

Thanks,

j

Re: capacitance-voltage depth profiling - request for info

Julie,
i'm not sure what you mean by a "well profile". There are problems with CV profiling unless you really understand what you are measuring, which is the free carrier concentration that has a Debye spreading to it. There is a similar problem with SRP, but a bit different since you are removing the material and this is more like differential Hall measurements. I decided to send this to a wider distribution since all of this was unraveled so long ago, only OLD guys like me even remember it. If you are trying to find a "well" with localized doping, you need to correct for this spreading to get the dopant distribution (Kleinfelder paper) and if it's inhomogeneous composition, as in a quantum well, then you need to account for the band discontinuities and their effect on the carrier distribution to get the band picture correct (Kroemer). I have attached a couple of OLD papers describing each issue. I am sure there is CV capability at SNF, but it would not be movable, but I think you can bring your samples here.
Regards,
Jim Harris
On Feb 10, 2011, at 10:44 AM, Segal, Julie wrote:

> Labmembers,
> We would like to use CV-profiling to characterize a well profile in silicon. (We have gotten conflicting results from SRP/SIMS.) Does anyone have a set-up for this that we might be able to borrow? (Capacitance meter with variable bias voltage, software, etc?) Or can you refer us to someone else who might have this capability?
> Thanks!
> - Julie
> !DSPAM:4d5433fa9782096920807!
>

James S. Harris '64
James & Ellenor Chesebrough Professor E-Mail:Harris@snow.stanford.edu
Department of Electrical Engineering http://www-ee.stanford.edu/~harris/
ALLEN Rm 328, 420 Via Palou Mall Ph: (650)723-9775
Stanford, CA 94305-4075 Fax: (650)723-4659
Adm. Asst.: Gail Chun-Creech Ph: (650)723-0983

capacitance-voltage depth profiling - request for info

Labmembers,
We would like to use CV-profiling to characterize a well profile in silicon. (We have gotten conflicting results from SRP/SIMS.) Does anyone have a set-up for this that we might be able to borrow? (Capacitance meter with variable bias voltage, software, etc?) Or can you refer us to someone else who might have this capability?
Thanks!
- Julie

Problem p5000etch SNF 2011-02-10 02:57:21: bonded piece detached from the wafer and lost in Chamber C

Please do not use Chamber C.

EE410 moving towards Electrical Test

All,

The final EE410 class lab sections are next week (2/14). Thank you
for the cooperation you showed as the groups moved through the
facility. Once the wafers are completed the class will move to the
electrical test platform in the TCAD room. Starting the week of Feb.
21st, and for the following couple of weeks the probe station will be
heavily utilized by the EE410 class. Please be aware the class has
priority and could be using the probe station around the clock during
these weeks.

Regards,

EE PhD Defense, Hyung Dong Lee (Wednesday, Feb 9th, 2011, 10:00 am, CISX Auditorium)

Stanford University Ph.D. Dissertation Defense

Title: "Understanding of NiO-based unipolar resistive switching"

Hyung Dong Lee
Electrical Engineering
Research Advisor: Prof. Yoshio Nishi

Data: Wednesday, Feb 9th, 2011
Time: 10:00 am (Refreshments served at 9:45 am)
Location: Paul G. Allen Building Auditorium (CISX 101X)

Abstract
  As NAND Flash memory technology is facing challenging issues such as electronic coupling between adjacent cells or high coupling of the control gate with floating gate in scaling down to and beyond 16nm technology node, investigations of new functional devices or materials has been attempted for next-generation memory technology to continue development of memory technology beyond 16 technology generation. One of new emerging non-volatile memories is resistance change random access memory(ReRAM) satisfying the requirements to replace NAND Flash; low cost, simple structure, promising 8nm technology node, low power dissipation, high endurance, possible integration in crossbar arrays in 3D.
  In ReRAM, understanding the switching mechanism was very complicated because there have been many different switching phenomena in circumstances under ultimate electrical stress. One of them, oxidation/reduction of transition metals is generally accepted for unipolar switching. In this switching phenomenon, both thermal and chemical processes are correlated with the effect of electric field. In this talk, to suggest clearer understanding of switching mechanism for unipolar switching, defect states in NiO are investigated, which are closely related to conductivity in the transition metal-based resistive materials. Setting up feasible "ON" and "OFF" states in atomic scale gave an insight into atomic structure of conductive filament, role of oxygen (or oxygen vacancies) and its migration. With the understandings from first principle simulations, physically quantitative model about reset/retention and filament formation could be suggested. In addition to that, obtained experimental results like reduction of reset current and long retention time of "ON" resistances due to inserted interfacial layer could be explained based on the quantitative model.

PhD Oral Examination, Cheng-Chieh Chao, Monday, Feb 14, 2011, 3:15 pm, McCullough 335

Stanford University Oral Examination

Cheng-Chieh Chao
Department of Mechanical Engineering
Advisor: Prof. Fritz B. Prinz

Monday Feb 14th, 3:15 pm (refreshments at 3 pm)
McCullough Building, Room 335

Atomic layer deposition for solid oxide fuel cells

Solid oxide fuel cells (SOFCs) are attractive for their high energy conversion efficiency in the usage of fuels ranging from hydrogen to hydrocarbons. Nevertheless, they have limited applications because this high efficiency cannot be achieved without high operating temperatures, which pose significant engineering challenges, diminishing the SOFCs practicality for applications such as portable power sources. Lowering the operating temperatures of SOFCs may improve thermal stability and offer shorter start-up times, which in turn might broaden their use as auxiliary power units for automobiles. Although many studies have aimed at lowering the SOFC operating temperatures, this temperature reduction has been inevitably accompanied by a decrease in the electrochemical performance, which is contributed by a larger activation loss and ohmic loss. These two losses are related to sluggish reaction kinetics at the electrode/electrolyte interface (interfacial resistance) and poor ionic conductivity in the electrolyte (electrolyte resistance) at reduced temperatures. In this talk, I will present the approaches to reduce both losses with the help of atomic layer deposition (ALD).

In the first approach, ALD was used to fine-tune the electrolyte surface properties, which improved the reaction kinetics at the electrode/electrolyte interface. In the second approach, the nucleation of ALD platinum catalyst was investigated by TEM to improve the catalyst nanostructure, which reduced the activation loss during fuel cell operation. In the third approach, ALD was used to fabricate an ultra-thin SOFC electrolyte, which reduced the ohmic loss during fuel cell operation. In the last approach, by combining the nanosphere lithography (NSL) and ALD process, a corrugated thin-film electrolyte was fabricated to provide a larger area for interfacial reactions. By reducing activation loss and ohmic loss with these approaches, the electrochemical performance of SOFC was improved at low temperatures.

request for small amount of SU-8

Hi,

 

I am wondering if anyone would be able to spare a few ml (~20 ml should be plenty) of SU-8 material and thinner to make dilutions. I would like to use it for testing to see if it is suitable to create a surface mold of fixed animal tissue surface. If you have some to spare, or have additional suggestions, please do let me know. Thank you for your help.

 

Regards,

 

James

 

***************************************
James Su, Ph.D.
Postdoctoral Scholar
Materials Science & Engineering
Heilshorn Lab
476 Lomita Mall
McCullough Hall, Rm 319
Stanford University
Stanford, CA 94305

jamessu@stanford.edu
Tel: 650.724.4768
***************************************

 

Re: Comment p5000etch SNF 2011-01-26 11:15:53: Replaced Freon 318 cylinder

Archived

Re: Problem p5000etch SNF 2011-01-19 14:52:12: Limits in HBr use in ChC

New cylinder has been installed. HBr sensor has been quiet.

Special Process Clinic, Today, 2-3 pm

Greetings labmembers!

Process Clinic today (Monday) from 2-3 pm. We meet in the cubicle area near Maureen's office.
We have a special guest: Bill Martin, representing mask making services. So, please bring your
processing questions, SpecMat requests, and mask layout questions. Staff, experienced labmembers
(and Bill Martin!) will be on hand to help brainstorm solutions and review requests. All in the
lab community are welcome.

Your SNF staff

--
Mary X. Tang, Ph.D.
Stanford Nanofabrication Facility
CIS Room 136, Mail Code 4070
Stanford, CA 94305
(650)723-9980
mtang@stanford.edu
http://snf.stanford.edu

About to run out of disk space ....

SNF Lab Members:

We are about to run out of disk space once again on the Sunrays. If
this happens, nobody will be able to run Coral or anything else.

There are two things that you can do to help:

1. Everyone can help by firing up Firefox and reducing the cache size to
about 5 MB. By default it is set to 50 MB and with the number of
labmembes that we have, that ends up consuming a lot of disk space.

To do this open firefox. For most versions, if you select the Edit menu
item there is a Preferences submenu item.
When that opens, click the Advanced icon and then the Network tab on the
panel that opens. Under "Offline storage" change the amount of space
used for the cache down to about 5 MB and then click the "Clear Now" button.
Then close the Preferences panel.

If everyone does this, it will help us significantly.

2. Some of your have large amounts of disk space in use. While the
staff members that are high on this list will be given a bit more
latitude, please look for big files that you can eliminate or have
stored on other machines. To get an idea of your biggest files, you can
log into a Sunray, open a terminal window and then issue the command:

du -k | sort -nr | more

which will list the biggest files or directories in your home
directory. If you see things that you no longer need, please get rid of
things.

Thanks,

John

Following is the ordered list of disk usage (in kB) for those folks who
have over 100 MB of disk usage. (100 MB = 100000 kb). Currently our
disks are listed as 100% full. That likely means that we are within an
hour or two of this machine .... including Coral ... grinding to a halt.

1225337 jwc
1044061 mtang
1020686 cbellew
666308 maurice
514516 maxms
440414 sbiaa
420633 chen0622
416189 lyjiao
374435 pnataraj
371071 gunjim
363839 vossough
358788 eenriquez
346010 mtan
338853 mvikram
325852 bchui
324741 naiqian
318531 rostam
301736 jtsai
285481 mislam
284875 chongxie
278637 karthikv
273455 mdickey
258185 popomoo
255130 cachang
253079 megrubbs
249337 svo
248300 jperez
234371 junil
232940 gyama
231869 ywidjaja
226998 calarrudo
224455 zpatel
223332 cmfaulkn
223216 renshen
219094 king
211709 nppatil
211496 eata
210093 liangjl
203080 chienyuc
201621 rparsa
199773 rik
195717 takuyan
193334 kosarb
192539 tomada
192356 mrlin
192325 mcvittie
187607 alsune
184189 haiwei
183427 wanglele501
181415 jennyhu
178817 ocakkaya
178459 ryw
178049 jcdoll
177225 fpurkl
172861 dongl
171585 hopcroft
168281 ghyrn
167067 faridz
167020 insun
166899 altug
166850 wanki
165991 gth
163867 fanzeng
163865 axiu
163237 dgunning
161021 pponce
160432 mkseo
159848 jweisse
157607 hrleebh
157520 dasgupta
156143 dalyx
154632 cbaxter
152729 junjun
152426 jsnapp
152118 jfoster
151430 sdogbe
151167 daesung
151009 jasonlin
150327 dkozak
150049 djwong
149880 cursive
149655 cmcg
148735 jhaydon
147845 yoavb
147671 jjeong1
147381 lindaw
147076 ajamo
144446 hktran
143156 fanpy
141970 jleu
141954 kghadiri
141621 dongrip
140797 mcherry
139546 chingmei
138855 aeonia
135831 dniemann
135829 pbrink
134022 suyog
133909 nharjee
133492 tdo
133376 sipark
133336 alexneu
132408 oisaadat
131581 ericp
131203 yoonjin
131032 xzhuan1
130979 haniff
129460 masaharu
128750 kimsangb
128662 rrick
128142 ybkim
126825 muchiao
125926 ehsans
124516 cfchiang
124385 ahazeghi
123848 erichall
123120 iwjung
122775 dpb167
122030 okilic
120981 swalker
120884 ginel
120535 rshyam
120399 damodei
118982 kattsai
118848 mnakamura
118775 kokab
118769 grupp
117261 jprovine
117053 barlian
116523 ylinn
115130 ludwig
114926 maryamzm
114683 yiyang
114405 lwchang
114404 dfulgencio
113957 jimkruger
113411 hsyoon
113260 malekos
112909 cdietz
111981 yinliu
111960 bdai
111956 jeh0513
111569 kupnik
111465 dwnam
111241 wslee
111125 zguo
111036 fatihs
110760 johana
110660 flannery
109791 audet
109535 clifton
108493 laurahughes
107844 kcbalram
107625 patlu
107336 takane
107231 whlee
106128 mmessana
105872 srikantv
105628 ytcheng
105048 vishal
104736 xuanwu
104599 ayz
104584 shuluc
104323 grahamab
104068 wangss
103655 evander
103650 jsegal
103466 zeyuan
103058 helencxy
102771 me342e
102499 mferrier
102327 mihirt
102318 mattm3
102316 awu
102137 kavehm
101992 jpadovani
101952 edfei
101801 arion
101299 asanders4
101240 rhenn
101184 ycjun
100612 novak
100379 kasliwal
100092 rlalley

(Reminder) MSE PhD Defense, Seong-Geon Park (Feb 7th, Monday, 10:30 am, CISX Auditorium)

University PhD Dissertation Defense

 

“The study of Resistive Switching Mechanism in TiO₂ using First Principles Calculation.”

 

Seong-Geon Park

 

Research Advisor: Prof. Yoshio Nishi

 

Monday, Feb 7^th, 2011,  10:30 am (Refreshments served at 10:15 am)

 

Location: Paul G. Allen Auditorium (CISX 101)

http://cis.stanford.edu/misc/directions.html

 

 

Abstract

Recently the interest in Resistive Random Access Memory (ReRAM) has been significantly increased, as it is now considered as the promising candidate for the next generation of non-volatile memory devices, due to its high density, low operating power, fast switching speed, and compatibility conventional CMOS process. Among many resistance switching materials, TiO₂ has been widely studied. However, the most challenging issue is that the underlying switching mechanism is lacking an in-debt understanding. It has been proposed that the resistance switching is strongly coupled to the presence and a preferential distribution of oxygen vacancies involving the formation of a conductive filament. Although many experiments have been done to address the switching mechanism during the last decade, it is hard to figure out what happens in microscopic level. Therefore systematic interpretation about the microscopic details of the role of oxygen vacancies in the formation of a conductive filament is essential.  To address the conduction and resistance switching mechanism, the effect of oxygen vacancies on the electronic structures in TiO₂ has been investigated using first principle study based on density functional theory.

 

In this talk, I will first discuss “ON”-state (Low Resistance State) conduction mechanism of rutile TiO₂ in terms of oxygen vacancies, and then the transition from “ON” to “OFF”-state (High Resistance State) will be demonstrated. Although it is known that TiO₂ exhibits n-type semiconducting conductivity with extra electron carriers generated by the formation of oxygen vacancies, “ON” and “OFF”-state conductivity during resistance switching cannot be explained by isolated single oxygen vacancy. I will demonstrate electronic characteristics such as density of states, electron localization function, band decomposed charge density distribution, and energy band structure, and show how they changes by oxygen vacancies. The influence of the number of oxygen vacancies and different configurations of multi vacancies on the resistance change will be discussed. Oxygen vacancy ordering and the diffusion of either vacancy or hydrogen has a significant impact on both the formation of a conductive filament and the transition from “ON” to “OFF”-state. Results from this work suggest “ON”-state conduction and resistance switching modeling that could be described by the formation and rupture of a conductive filament incorporating oxygen vacancy ordered structure.

SNF renovation project

SNF labmember and faculty communities:

As most of you are aware, we won a $4.2M stimulus grant from the NSF
last year that will allow us to upgrade the SNF's infrastructure, as
well as expand our capabilities with a new nanosynthesis lab to be
located in the maintenance staff's office area. Stanford is
contributing another $2M toward this project.

Ashok Singh is the project manager from DPM and together with an
architectural and engineering firm, we're preparing the RFP for the
project, which will be announced in mid-March. The selection of the
general and sub contractors on the "design/build" project will be made
by early May.

This major investment will give us all a more capable facility.
However, we will need to do two shutdowns during December - January of
this year (2011-2012) and next (2012-2013). The precise timing and
duration of the shutdowns will be determined, once the contractors dig
into the logistics of the process. The duration is likely to be 4-6
weeks. As more detailed plans are developed, we will do our best to
announce those things that affect the availability of SNF to allow you
to plan your research activities accordingly.

Roger

Re: Problem p5000etch SNF 2011-02-04 10:44:37: wafer inside

Recovered the user's wafer. User forgot to enter a chamber recipe.

EE PhD Defense, Hyung Dong Lee (Wednesday, Feb 9th, 2011, 10:00 am, CISX Auditorium)

Stanford University Ph.D. Dissertation Defense

Title: "Understanding of NiO-based unipolar resistive switching"

Hyung Dong Lee
Electrical Engineering
Research Advisor: Prof. Yoshio Nishi

Data: Wednesday, Feb 9th, 2011
Time: 10:00 am (Refreshments served at 9:45 am)
Location: Paul G. Allen Building Auditorium (CISX 101X)

Abstract
As NAND Flash memory technology is facing challenging issues such as electronic coupling between adjacent cells or high coupling of the control gate with floating gate in scaling down to and beyond 16nm technology node, investigations of new functional devices or materials has been attempted for next-generation memory technology to continue development of memory technology beyond 16 technology generation. One of new emerging non-volatile memories is resistance change random access memory(ReRAM) satisfying the requirements to replace NAND Flash; low cost, simple structure, promising 8nm technology node, low power dissipation, high endurance, possible integration in crossbar arrays in 3D.
In ReRAM, understanding the switching mechanism was very complicated because there have been many different switching phenomena in circumstances under ultimate electrical stress. One of them, oxidation/reduction of transition metals is generally accepted for unipolar switching. In this switching phenomenon, both thermal and chemical processes are correlated with the effect of electric field. In this talk, to suggest clearer understanding of switching mechanism for unipolar switching, defect states in NiO are investigated, which are closely related to conductivity in the transition metal-based resistive materials. Setting up feasible "ON" and "OFF" states in atomic scale gave an insight into atomic structure of conductive filament, role of oxygen (or oxygen vacancies) and its migration. With the understandings from first principle simulations, physically quantitative model about reset/retention and filament formation could be suggested. In addition to that, obtained experimental results like reduction of reset current and long retention time of "ON" resistances due to inserted interfacial layer could be explained based on the quantitative model.

Problem p5000etch SNF 2011-02-04 10:44:37: wafer inside

Wafer loaded into the front chamber but not the process chamber B. Process in chamber B did not start.

Re: Problem p5000etch SNF 2011-02-03 16:48:04: No HBr

HBr turned back on

copper CMP

Hi all,

I'm sorry to spam you again. Does anybody have experience doing copper CMP (chemical mechanical planarization) either at Stanford or with a company in the bay area? If so, could you please contact me, I have a few questions.
Thank you for your help.

Francois

Problem p5000etch SNF 2011-02-03 16:48:04: No HBr

Re: Problem p5000etch SNF 2011-02-03 10:45:09: wafer didin't come out from chamber C

Recovered the wafer. The clamp intermittently did not stop at the release during the unload. Adjusted the clamp's pneumatic cylinder mid position metering valve.

Al thermal evaporation

Hi All

I want to do thermal evaporation of Al with a thickness of ~ 300 nm and encounter a problem. It is corrosive at high temperature and damage the boat easily. Also, molten Al tend to travel around the boat and cause short circuit between electrodes.

Since we do not have the capability of modifying source feeding mechanism. Is there any way we can improve on the boat? Like additional coating or wetting additives to confine the molten Al. Please give us any suggestion that could be helpful. Thank you very much for your help!

Hungtao

Problem p5000etch SNF 2011-02-03 10:45:09: wafer didin't come out from chamber C

Re: Problem p5000etch SNF 2011-02-01 16:55:29: HBR turned off

HBr is back on

PHD Defense - Fabrication Methods for Environmentally Hardened Sensors

 

 

Department of Electrical Engineering

University PhD Oral Examination

Fabrication Methods for Environmentally Hardened Sensors

Anthony F. Flannery Jr.

February 3, 2011 @ 2:00 PM

Refreshments at 1:45 PM

CIS-X 101 (Auditorium)

Abstract

Micromachined sensors have continued to open exciting new doors in the field of metrology. Applications for different types of sensors and sensing systems have proven a fertile ground for cross-disciplinary research and many new sensor developments are being made in the fields of biology, pharmacology, chemistry, and genetics. The need for sensors that can function successfully in a broad range of environments is clear. Whether the task is to produce devices which can tolerate harsh chemical environments or those which will not interfere with delicate biochemical processes, developments in both materials and fabrication techniques will continue to be necessary as sensors leave the laboratory and interface with the real world.

In this work, a process for low-temperature, low-stress PECVD silicon carbide was developed. The deposition conditions were CMOS compatible. This also makes the film suitable for devices with gold and other materials with lower temperature limits. Key electrical and physical properties relevant to micromachined transducers were determined. The chemistry of the film was also investigated and an important criterion to achieve chemical resistance was discovered, adding understanding to its usefulness in fabricating environmentally hardened transducers.

Work was also done developing two main fabrication techniques. The first was an improved method for depositing and patterning high stress metals, specifically iridium. Iridium is of particular interest because of its useful electrochemical properties and its chemical resistance. Advancements were made in the areas of stress reduction and liftoff structures. The second was in the area of non-planar lithography, allowing the application of chemically resistant coatings on the sidewalls of microfluidic structures.

These techniques were applied in several different applications. An iridium microelectrode array capable of performing electrochemical analysis in hydrofluoric acid was fabricated and tested. The effect of coating a micromachined pressure sensor was explored. A gasketing process for fabricating chemically resistant microfluidic channels was proposed and fabricated.

 

RE: Local vendor/service to fix Temptronic temperature controller

Hello Jenny,

If you have issues with Temptronics chuck or controller, I believe that you have to call directly their service Engineer. I can check who is the service Engineer for the bay area.

Best Regards,

Mahesh Hingorani
Semi Test Solutions
4423 Fortran Drive #190
San Jose, CA 95134
Cell: 510-468-9769

-----Original Message-----
From: Matthew Kerby [mailto:mkerby@stanford.edu]
Sent: Wednesday, February 02, 2011 4:08 PM
To: 'Jenny Hu'; 'labmembers'
Cc: mahesh@semitestsolutions.com
Subject: RE: Local vendor/service to fix Temptronic temperature controller

Here is a local probe station vendor who may be able to help you.

Mahesh Hingorani
Semi Test Solutions
4423 Fortran Drive #190
San Jose, CA 95134
Cell: 510-468-9769
http://www.semitestsolutions.com

-----Original Message-----
From: Jenny Hu [mailto:jennyhu@stanford.edu]
Sent: Wednesday, February 02, 2011 3:15 PM
To: labmembers
Subject: Local vendor/service to fix Temptronic temperature controller

Hi Labmembers,

Does anyone know of a local vendor/service company for fixing Temptronic temperature controllers or Cascade Microtech probe stations? Thanks in advance for your help!

Sincerely,
Jenny

RE: Local vendor/service to fix Temptronic temperature controller

Here is a local probe station vendor who may be able to help you.

Mahesh Hingorani
Semi Test Solutions
4423 Fortran Drive #190
San Jose, CA 95134
Cell: 510-468-9769
http://www.semitestsolutions.com

-----Original Message-----
From: Jenny Hu [mailto:jennyhu@stanford.edu]
Sent: Wednesday, February 02, 2011 3:15 PM
To: labmembers
Subject: Local vendor/service to fix Temptronic temperature controller

Hi Labmembers,

Does anyone know of a local vendor/service company for fixing Temptronic temperature controllers or Cascade Microtech probe stations? Thanks in advance for your help!

Sincerely,
Jenny

Local vendor/service to fix Temptronic temperature controller

Hi Labmembers,

Does anyone know of a local vendor/service company for fixing Temptronic temperature controllers or Cascade Microtech probe stations? Thanks in advance for your help!

Sincerely,
Jenny

RE: polishing alumina / SiO2

Hello all,

I am also interested in knowing this. My samples are also small chips
(10x10mm) with SiO2 substrates. Instead of alumina, I would like to polish
samples covered with thin SiO2 (< 100nm spin-on-glass) with a similar rate
and surface roughness.
Thanks a lot for your help.

Yao-Te

-----Original Message-----
From: Francois Amet [mailto:amet@stanford.edu]
Sent: Wednesday, February 02, 2011 2:20 PM
To: labmembers@snf.stanford.edu
Subject: polishing alumina

Hi all,

I need to polish samples covered with alumina (ALD grown) down to 1nm rms
roughness or less. The underneath substrate is SiO2, and the etch rate of
alumina should be slow enough (a few nm per minute). The samples are small
chips (5x5mm or 15x15mm) Does anybody know a company in the bay area which
could do this job?
Thank you very much for your help!

Francois

polishing alumina

Hi all,

I need to polish samples covered with alumina (ALD grown) down to 1nm rms roughness or less. The underneath substrate is SiO2, and the etch rate of alumina should be slow enough (a few nm per minute). The samples are small chips (5x5mm or 15x15mm) Does anybody know a company in the bay area which could do this job?
Thank you very much for your help!

Francois

Problem p5000etch SNF 2011-02-01 16:55:29: HBR turned off

Re: Problem p5000etch SNF 2011-01-28 16:06:23: No HBr

Fire trucks outside the building this afternoon ....

SNF Lab Members and Allen Building Occupants:

A number of you likely saw the PAFD trucks with lights flashing along
Via Pueblo this afternoon.

Some of the crews working in the steam tunnels that run under Via Pueblo
detected an odor that they could not identify and called in PAFD. The
Fire Department investigated all steam tunnels and all surrounding
buildings both in person and with detectors and could not identify
either the source of the odor or what it may have been. There were no
detectable levels registered on the sensors that they have that include
natural gas, hydrogen sulfide and flammable gas. In fact, only the
first people on the scene seemed to have smelled it and later-arriving
personnel were unable to smell/detect anything.

Some SNF lab members and building occupants know that there have been
occasional unpleasant smells in and around the building for the past
couple of months .... often later in the evening or in the early morning
... that have also resisted identification. At this point, we do not
know whether the late night/early morning smell is the same as was
present this afternoon and nobody has been able to identify the source
or the nature of the odor but, whatever it is, it does not register on
available sensors as a toxic or flammable gas. PAFD left the scene
convinced that there was no immediate hazard but also unable to find a
plausible source for these odors.

If you smell any strange odors in and around the building, please let
building staff or University EH&S know in hopes that any strange odors
can be identified.

Thank you for your continued support,

John

Comment p5000etch SNF 2011-02-01 14:40:12: Replaced HBR cylinder

Re: ITO deposition

Hi all,

Thank you for help.

If other members want to deposit ITO, following email thread would be useful.

Thanks again, lab members.

Boram

Han-Bo-Ram Lee, Ph.D
Bent Research Group
Department of Chemical Engineering
Stanford University

Mail : Rm 113, Stauffer III Bldg., 381 North South Mall, Stanford, CA 94305
Email : sixram[at]stanford.edu or sixram[at]gmail.com
WWW : bentgroup.stanford.edu/

On Tue, Feb 1, 2011 at 10:43 AM, Alex Butterwick <abutterwick@gmail.com> wrote:

Hi Boram,

I was wondering if you learned anything.  We are also interested in depositing ITO.  I know the Berkeley microfab lab has the capabilities and we've thought about doing it there.

Thanks for your help.

Best,

Alex

On Jan 26, 2011, at 4:54 PM, Han-Bo-Ram Lee wrote:

Hi all,

Is there anyone know about available ITO deposition by sputtering?

It's not matter that the chamber is in a lab or from company service.

Thanks in advance.

Boram

Han-Bo-Ram Lee, Ph.D
Bent Research Group
Department of Chemical Engineering
Stanford University

Mail : Rm 113, Stauffer III Bldg., 381 North South Mall, Stanford, CA 94305
Email : sixram[at]stanford.edu or sixram[at]gmail.com
WWW : bentgroup.stanford.edu/

Seminar Today: 4:00 pm, Allen 101X: Prof. L.-S. Fan

FYI, great seminar this afternoon.

Jose I. Padovani
----------------

Flexible 4,096-Pixel Multi-Electrode Arrays of Electrodes, CMOS and Image
Sensors: a tool for interfacing retinal circuitry and a basis for retinal
prosthesis
Long-Sheng Fan
National Tsing Hua University/Univ. California, Berkeley


Abstract
To achieve localized retinal neural stimulation with high granularity over
reasonable field of view within power constraints, we integrated a flexible
4,096-element retina chip 30 mm in thickness using a flexible 180nm CMOS
Image Sensor (CIS) technology. The retina chip is 3x3 mm in size (including
multiplexing electronics for pixel characterizations) with an array of 10 mm
electrodes and photo sensors 30 mm in pitch. The flexible format allows
better proximity between electrodes and retina neurons for localized
stimulation, and the integrated local electronics allows supplying
individual electrode the adequate and appropriate stimulation waveforms
right next to each individual electrodes. The chip senses local light
intensity and generates corresponding biphasic current at each pixel. Images
are projected onto the chip and corresponding biphasic currents for
stimulating retina tissue from each pixel are mapped. Loose patch and
whole-cell patch clamp techniques in vitro are used to characterize the
mouse retinal ganglion cells responses on these arrays with bipolar cells
facing down. With local active devices and signal processing capability, it
could also potentially be an enabling tool to interface retinal neurons to
the individual cell level for studying retinal neural network.

Biography
Long‑Sheng Fan received his MS & Ph.D. degrees in Electrical Engineering
and Computer Sciences both from the University of California at Berkeley. He
joined IBM Almaden Research Center as a Research Staff Member working on
magnetic sensors, AFM recording and he was an original advocator for
dual-stage servo in magnetic drives and demonstrated a magnetic recording
servo track density beyond 50kTPI using a multilevel metal MEMS
microactuator technology, which was transferred to an IBM pilot line. He
has served as a section editor for Sensors and Actuators (1994‑1997), a
government consultant and a member of proposal review panel of NSF and NIH,
and he is the IEEE Technical Program Vice Chair of Transducers 2009 and
designated Technical Program Chair of IEEE Transducers 2011. Dr. Fan joined
National Tsing-Hua University as a Tsing-Hua Professor and the Director of
the Institute of Nano Engineering and MicroSystems during 2003-9, and he was
the coordinator of Heterogeneous Integration Program of the SoC National
Program in Taiwan, promoting MEMS IP reuse with standard process modules &
EDA for MEMS/IC co-design. He is an IEEE Fellow and currently a Visiting
Professor in EECS, UCB. His academic research interest is in the biomedical
microsystems for medical implants & MEMS-enabled medical instruments.