May 2014 - BNC-all - ecn.purdue.edu

BNC E-news for the week of June 2nd
by Anthrop, Heather L 30 May '14

30 May '14

Seminar Survey Feedback Tours Seminar Dr. Jorge Garcia-Canadas Impedance Spectroscopy Methods Applied to Thermoelectric materials and Devices Tuesday, June 10th at 2:00 pm Birck 1001 For more information please visit: https://nanohub.org/groups/bnc/calendar/details/1024 Survey Feedback Citizenship Recognition - Andy Yang A special 'thank you' and recognition to user Andy Yang for his exemplary citizenship! Andy was working in the cleanroom over Memorial Day weekend, and on that Saturday Dave Lubelski came in to address an evaporator issue. Andy asked Dave to stay and support him while he worked in an acid hood. Andy did not want to work alone in the acid hood because it is a safety issue and a violation of policy. Thanks, Andy, for setting a fine example of being a responsible user of our facilities! Spinner 1 Spinner 1 has had intermittent vacuum issues. At times this has been caused by photoresist getting into the vacuum lines. This past week we found a loose vacuum line fitting and corrected it, so we believe another root cause of the vacuum problems has been found and fixed. Please let us know how Spinner 1 performs now that we have made this correction. VB6 Another height adjustment issue was brought to our attention. We would like to discuss this in person with the user so that we may permanently address the problem, so would the user please contact Bill Rowe or myself to discuss this in more detail? Thanks again for the constructive suggestions! Ron Tours There will be several tours in the month of June. Tuesday, June 3rd 2:45 pm - 15 guests Wednesday, June 4th 2:30 on - 2 guests Thursday June 5th 9:30 am - 8 guests Friday, June 6th 10:15 am - 24 guests Thank you, Heather L Anthrop Purdue University Birck Nanotechnology Center 1205 West State Street West Lafayette, IN 47907 (765) 494-7053

1 0

Defense exam: Sambit Palit, May 30th, 10:00AM, BRK 1001
by Sambit Palit 29 May '14

29 May '14

Dear all, I invite you for some free food, snacks and coffee on the occasion of my final defense examination. The details are as given below. Regards, Sambit Date: Friday, May 30th Time: 10:00 AM Location: Birck 1001 Title: Charging and Breakdown in Amorphous Dielectrics: Phenomenological Modeling Approach and Applications Abstract: Amorphous dielectrics of different thicknesses (nm to mm) are used in various applications. Low temperature processing/deposition of amorphous thin-film dielectrics often result in defect-states or electronic traps. These traps are responsible for increased leakage currents and bulk charge trapping in many associated applications. Additional defects may be generated during regular usage, leading to electrical breakdown. Increased leakage currents, charge trapping and defect generation/breakdown are important and pervasive reliability concerns in amorphous dielectrics. We first explore the issue of charge accumulation and leakage in amorphous dielectrics. Historically, charge transport in amorphous dielectrics has been presumed, depending on the dielectric thickness, to be either bulk dominated (Frenkel-Poole (FP) emission) or contact dominated (Fowler-Nordheim tunneling). We develop a comprehensive dielectric charging modeling framework which solves for the transient and steady state charge accumulation and leakage currents in an amorphous dielectric, and show that for intermediate thickness dielectrics, the conventional assumption of FP dominated current transport is incorrect, and may lead to false extraction of dielectric parameters. We propose an improved dielectric characterization methodology based on an analytical approximation of our model. Coupled with ab-initio computed defect levels, the dielectric charging model explains measured leakage currents more accurately with lesser empiricism. We study RF-MEMS capacitive switches as one of the target applications of intermediate thickness amorphous dielectrics. To achieve faster analysis and design of RF-MEMS switches in particular, and electro-mechanical actuators in general, we propose a set of fundamental scaling relationships which are independent of specific physical dimensions and material properties; the scaling relationships provide an intrinsic classification of all electro-mechanical actuators. However, RF-MEMS capacitive switches are plagued by the reliability issue of temporal shifts of actuation voltages due to dielectric charge accumulation, often resulting in failure due to membrane stiction. Using the dielectric charging model, we show that in spite of unpredictable roughness of deposited dielectrics, there are predictable shifts in actuation voltages due to dielectric charging in RF-MEMS switches. We also propose a novel non-obtrusive, non-contact, fully electronic resonance based technique to characterize charging driven actuation shifts in RF-MEMS switches which overcomes limitations in conventionally used methods. Finally, we look into the issue of defect generation and breakdown in thick polymer dielectrics. Polymer materials often face premature electrical breakdown due to high electric fields and frequencies, and exposure to ambient humidity conditions. Using a field-driven correlated defect generation model, coupled with a model for temperature rise due to dielectric heating at AC stresses, we explain measured trends in time-to-breakdown and breakdown electric fields in polymer materials. Using dielectric heating we are able to explain the observed lifetime and dielectric strength reduction with increasing dielectric thicknesses. Performing lifetime measurements after exposure to controlled humidity conditions, we find that moisture ingress into a polymer material reduces activation barriers for chain breakage and increases dielectric heating. Overall, this thesis develops a comprehensive framework of dielectric charging, leakage and degradation of insulators of different thicknesses that have broad applications in multiple technologies.

1 0

FW: Business @ Purdue News -- BUSINESS UPDATE -- May 28, 2014
by Anthrop, Heather L 28 May '14

28 May '14

Business@Purdue News<mailto:Business@Purdue%20News> Released: May 28, 2014 ________________________________ BUSINESS UPDATE Resume Normal Ariba Operations The errors have been resolved and normal Ariba activity may resume. Requisitions that were created today have automatically processed. The Split by Amount enhancement was implemented last night, which caused the errors. Requesters may now use the functionality in split accounting by amount. For step by step instructions, please see the Split Accounting in Ariba QRC<https://spa2010.itap.purdue.edu/Business/businessatpurdue/_layouts/WordView…>. For additional assistance, contact the Procure-to-Pay Helpdesk<mailto:pshelpdesk@purdue.edu> or call 765-49-47279. Contact: Cindi Stinebaugh, Procurement Services, stinebau(a)purdue.edu<mailto:stinebau@purdue.edu>

1 0

Business @ Purdue News -- BREAKING NEWS -- May 28, 2014 - 9 a.m.
by Anthrop, Heather L 28 May '14

28 May '14

If you have any questions or concerns please see the business office. Business@Purdue News<mailto:Business@Purdue%20News> Release Date: May 28, 2014 - 9:00 am ________________________________ Breaking News Discontinue Use of Ariba Until Further Notice Ariba requisitions are currently failing. Please discontinue submitting, editing, deleting, or approving requisitions until further notice. A Business Update will be sent as more information is available. ________________________________ Contact: Cindi Stinebaugh, Procurement Services, pshelpdesk(a)purdue.edu<mailto:pshelpdesk@purdue.edu>, 47279

1 0

BNC e-news for the week of May 26th
by Anthrop, Heather L 23 May '14

23 May '14

Holiday In observance of Memorial Day, Purdue University will be closed Monday, May 26th. Thank you, Heather L Anthrop Purdue University Birck Nanotechnology Center 1205 West State Street West Lafayette, IN 47907 (765) 494-7053

1 0

Spring Fling - May 22nd
by Turner, Jaime J 21 May '14

21 May '14

Dear all, Please be aware that Spring Fling is tomorrow May 22nd. Offices will be closed in Birck between 11-11:30am (for the rest of the day) for staff to attend. Please be aware of this and plan accordingly. Thanks! Jaime Turner Birck Nanotechnology Center 1205 West State Street West Lafayette, IN 47907-2057 Email: jjturner(a)purdue.edu<mailto:jjturner@purdue.edu> Phone: 765-494-3509

1 0

BNC e-news for the week of May 19th
by Anthrop, Heather L 16 May '14

16 May '14

NCN-NEEDS Summer School Purchasing PVD Users Seminar Survey Feedback NCN-NEEDS Summer School Spintronics: Science, Circuits, and Systems July 23 - 25, 2014 Martin Jischke Hall room 1001 For more information please visit: https://nanohub.org/groups/needs/summer_school Purchasing For a purchase request to be fully processed an explanation of why the purchase is being made MUST be filled out on the purchase request form. For the most current form please visit: https://nanohub.org/groups/bnc/File:DP_Purchase_Request.xlsx PVD Users Due to a recent power/grounding issue in bay "K" of the cleanroom, power supplies from the "Lesker and Leybold" evaporators have been damaged. These must be sent back to the factory for repair. Until the repairs are completed, we have formulated a plan to keep all users research moving in the right direction. For normal Lesker processes, the CHA will be the evaporator to use. We can shift the processes from the Leybold to the Varian or Airco. A new Sputtering system will come online the week of 05/26/14 that will be able to sputter the following materials: Ti, Au, Cu, TiO2, Al2O3, Al, Al/Si1%, Si3N4 and soon to be Ni and SiO2. For the time being, all samples will have to be submitted to Dave Lubelski for deposition. Once the evaporators are back online, training will begin for the sputtering system. Please give a minimum notice of 24 hours for sputtering source changes. Thank You, Dave Lubelski Seminar Professor Gregory B. Raupp Director, Macro Technology Works Initiative Arizona State University High Performance Flexible Electronics for Revolutionary Human-scale Systems: Thinking Outside the Box Monday, May 19th at 11:00 am in Birck 1001 For more information please visit: https://nanohub.org/groups/bnc/calendar/details/995 Survey Feedback Optical Microscopes Concerns about our two Nikon optical microscopes were recently brought to our attention and we immediately scheduled a microscope field service engineer to come in for a preventive maintenance visit. Last Friday he completed a general service on both scopes, cleaning the optics and light path, and checking the mechanical movement. A minor part for the 'north' scope has been ordered and will be installed when it arrives. Both scopes are in good working order. Also please note the Nomarski filters are available and located in the plastic container next to the microscopes. Please feel free to use these as needed, and return them to the storage box when finished. Equipment Availability We've had a number of comments from students and other users stating that it can be difficult to gain access to equipment and/or staff for training and processing. Our recent analysis shows equipment is actually being used, based on a 24/7 use model, only 20 - 30 % of the time it is available. And our equipment uptime, thanks to our engineering staff, is more than 90%. This analysis is done by looking back into Coral reports at the real usage times. So actual equipment availability is good but there is a large problem where equipment reservations are made in Coral and then not used and not cancelled. When unused reservations are not cancelled it blocks others from being able to use the tools. This situation happens for a variety of legitimate reasons . . . previous processing steps may have had issues so the samples aren't ready when planned for the reserved equipment time, additional measurement or characterization time is required prior to the next processing step, personal issues arise which cause research progress to be temporarily suspended, etc. For this fiscal year (since July 1, 2013) we have compiled a report from Coral which shows that 20 users accounted for 2554 reservations that were missed and not cancelled. Therefore there were 2554 instances since last July where Coral shows equipment blocked from use by unused reservations. We are seriously evaluating changes in our operational systems to address this issue, and we would welcome suggestions from the user community. In the meantime, please be diligent about cancelling your reservations when you realize they are not going to be used. This frees up equipment in Coral for other users and relieves the pinch points that many of you have noted. Thanks again for your inputs, and your cooperation, and we look forward to receiving your ideas on how we can address this issue. Ron

1 0

Bagwell Lecture, Federico Capasso, Wednesday May 14, 2pm Burton Morgan 121
by Shakouri, Ali 12 May '14

12 May '14

Dear Colleagues: I would like to invite you to attend the 2014 Bagwell Lecture at Burton Morgan 121 on Wednesday May 14, 2-3pm. Prof. Federico Capasso from Harvard University will talk about "New Frontiers in Optics and Photonics with Designer Electronic and Optical Materials." (see below the abstract). This lecture series was established in honor of Professor Philip F. Bagwell, who passed away in 2002. Professor Bagwell did pioneering work on mesoscopic electron transport, on semiconductor-superconductor heterojunctions, and on related devices. His interest was in the underlying physics. His quest was for fundamental understanding and his objective was to boil down complex problems down to clear descriptions and fundamental contributions. He thought deeply about problems, but also had a broad range of interests. I look forward to see you on Wednesday. Best regards, Ali Bagwell Lectures: ---------------------- 2004 Herbert Kroemer 2005 Albert Overhauser 2007 Jeff Hawkins 2009 Steven J. Hillenius 2010 Eugene A. Fitzgerald 2011 Zhores I. Alferov 2011 Wilfried Haensch 2014 Federico Capasso ----------------------- New frontiers in Optics and Photonics with Designer Electronic and Optical Materials Federico Capasso capasso(a)seas.harvard.edu<mailto:capasso@seas.harvard.edu> School of Engineering and Applied Sciences Harvard University, Cambridge, MA 02138 Wednesday, May 14, 2 - 3pm; Burton Morgan 121 The control of electrons and photons in artificially structured materials at the nanoscale by quantum and electromagnetic design has opened unique opportunities for major advances in science and technology. I will present a tutorial account of some these developments. From the design of the electronic resonances and their coupling to light in nanometer thick materials a new class of light sources (quantum cascade lasers) has emerged that now cover almost the entire infrared and far-infrared spectrum, leading to an explosive growth in applications. By structuring surfaces at the sub-wavelength with nanoscale optical resonators and nanometer thin layers "metasurfaces" have emerged that have led to powerful generalizations of the laws or reflection and refraction, new thin film interferences and new ways to generate light beams and surface optical waves with "arbitrary" wavefronts. Applications of this new "flat optics" will be presented. Finally, I will show how quantum fluctuations at the nanoscale can be designed to control macroscopic quantum electrodynamical phenomena such as attractive and repulsive Casimir forces and their interaction with micro/nanomechanical structures. Federico Capasso is the Robert Wallace Professor of Applied Physics at Harvard University, which he joined in 2003 after a 27 years career at Bell Labs where he did research, became Bell Labs Fellow and held several management positions including Vice President for Physical Research. His research has spanned basic science and applications in the areas of electronics, photonics, nanoscale science and technology including plasmonics, metasurfaces and the Casimir effect. He pioneered banstructure engineering of artificially structured materials and devices and invented the quantum cascade laser. He performed the first measurement of the repulsive Casimir force. He and his group recently discovered powerful generalizations of the laws of reflection and refraction applicable to metasurfaces and demonstrated that the latter can be used to design new planar optical components (flat optics). He is a member of the National Academy of Sciences, the National Academy of Engineering, a fellow of the American Academy of Arts and Sciences; His awards include the King Faisal International Prize for Science, the American Physical Society Arthur Schawlow Prize, the Wetherill Medal of the Franklin Institute, the IEEE Edison Medal, the SPIE Gold Medal, the European Physical Society Quantum Electronics Prize; the Berthold Leibinger Zukunftspreis (the future prize), the Julius Springer Prize for Applied Physics, the Jan Czochralski Award of the European Material Research Society for lifetime achievements in Materials Science; the IEEE D. Sarnoff Award in Electronics, the IEEE/LEOS Streifer Award, the Optical Society of America Robert Wood prize, the Rank Prize in Optoelectronics, the Material Research Society Medal, the Welker Medal, the Duddell Medal and Prize of the Institute of Physics (UK), the Newcomb Cleveland Prize of the American Association for the Advancement of Science, the "Vinci of Excellence" LMVH Prize and the New York Academy of Sciences Award.

1 0

BNC e-news for the week of May 12th
by Anthrop, Heather L 09 May '14

09 May '14

Parking Seminar Survey Feedback Training Parking 20 parking spaces have been reserved from 10:00 am - 3:00pm on May 14th for an event in DLRC. Seminar Alexander V. Kildishev Quantum Photonics Faculty Candidate Seminar Ongoing Transformation of Computational Nanophotonics Thursday, May 15th at 9:30 am in Birck 1001 For more information please visit: https://nanohub.org/groups/bnc/calendar/details/993 Survey Feedback Vistec VB6 We have received input that the Vistec VB6 electron beam system has had maintenance and process issues. We would like to briefly summarize the approach we've been taking to resolve the problems. Vistec engineering and field service have worked diligently with us to find and fix system problems, and over the last 7 years Vistec has spent over a half-million dollars (under maintenance contracts) on parts to fix issues as they were found. That does not include the Vistec engineers' time and expenses. (It is in Vistec' s best interest to keep our machine functioning at a high level). Since the upgrade to Linux on our control system last year the software is checking parameters that the previous VAX/VMS software was incapable of checking. This significantly moved us forward to improve the machine uptime and improve the capability of the system through various machine checks and calibrations. Two system tests, a stitch test and a stability test, gave results that were within machine specification. Vistec is currently reviewing what other tests could be run to help indicate any issues that could be addressed. We have also uncovered some unreported user-generated problems. Recently we had a problem due to a user entering a value into the machine which was incorrect. It was fixed quickly and the machine was immediately returned to use. Last week a height problem was plaguing some users. A user had not followed procedure on loading of the cassette into the microscope and disturbed the height setting for all subsequent users. They did not report the problem and the next users assumed it was a VB6 problem. Once discovered the problem was fixed in 30 minutes . . . the height is fine now for all cassettes. When things aren't working correctly please report them to Bill Rowe as soon as they are noticed so that Bill can address them right away. We are still working closely with Vistec to make improvements on the VB6. Just this week they sent a new scan generator board to make improvements in our video. We are also waiting on one of their programmers to fix a problem in our software that would allow us to look at the video on our two large monitors rather that our stand-alone monitor. Information has also been exchanged with Vistec about the warnings we receive in the job calibration program for stigmation. We continue to strive to make the VB6 a machine with high uptime and very good capabilities, taking a continuous improvement approach with Vistec as our key partner in these efforts. Equipment Maintenance We have received some feedback that our process equipment suffers from low uptime and that maintenance is an issue, but nothing specific was noted. I would ask that future such inputs be a little more specific so that we may address specific process areas/equipment as they arise. Thanks again for the very constructive feedback. Ron Training Employees who use Concur Travel and Expense to arrange travel, create travel requests and expense reports can gain some hands-on experience by attending TRVLC 200 - Concur Traveler Training. For more information please visit: Traveler Training Offered in May<https://spa2010.itap.purdue.edu/Business/_layouts/CopyUtil.aspx?Use=id&Acti…>

1 0

Three quick updates/notes
by Peroulis, Dimitrios 09 May '14

09 May '14

Dear all, 1. Thank you all for your very useful comments in our weekly cleanroom feedback surveys over the past 6 weeks. As you may have already noticed in the last couple of weeks, we are now including actions we are taking based on your comments to every weekly Friday memo. If you don't see an action based on your response, it does not mean we have ignored it. It simply may require a longer-term action plan from our side. 2. The feedback survey is now online! Just go to https://nanohub.org/groups/bnc/users and click the survey link under operations. If you prefer a direct link, please check this one<https://purdue.qualtrics.com/SE/?SID=SV_eQbN3nYi83Hhzk9>. 3. With the end of the semester nearing, please check and identify any chemicals you will no longer need. Please see Ira for disposal. Also as a reminder chemicals are not to be stored in totes and all chemicals going onto the cleanroom need to go through Ira. This is ensure that the containers are cleanroom compatible and maintain our chemical inventories. Thank you, Dimitri ________________________________________________________________________________ Dimitrios Peroulis Professor, School of Electrical and Computer Engineering Deputy Director, Birck Nanotechnology Center Purdue University 1205 West State Street West Lafayette, IN 47907-2057 tel: (765) 494-3491, fax: (765) 494-4731 email: dperouli(a)purdue.edu<mailto:dperouli@purdue.edu> http://sites.google.com/site/peroulisteam/ ________________________________________________________________________________

1 0