Final Sabbatical Report to the University of Wisconsin-Platteville
December 15, 2015
Harold T. (Hal) Evensen
Engineering Physics
My 2014-2015 sabbatical with the Advanced Materials for Energy and Electronics
Group, in the department of Materials Science and Engineering at UW-Madison, was
a rewarding experience professionally, academically, and personally. I worked with
Professor Mike Arnold’s group and learned to isolate semiconducting carbon
nanotubes (CNTs) and much of the surrounding technology and terminology around
carbon nanotube-based electronics. Most significantly, I learned to fabricate aligned
monolayer films of carbon nanotubes (CNTs) using a process recently developed by
that group (but not well understood). In order to gain an understanding of the
process, we constructed a computer-controlled apparatus to study the deposition
process and gain reproducibility. We gained some crucial insights on the process,
and also produced large (~1 inch square) areas of aligned CNTs, much larger than
the previous ‘record’ of 20 micrometer squares. This work has had two continuing
impacts: (1) I have continued this research to support eight UW-Platteville student
researchers in the Fall 2015 semester; (2) I successfully applied for a National
Science Foundation Research Opportunity Award, which funded a portion of my
sabbatical: I feel strongly that this path could be used by other faculty on our
campus.
Pre-Sabbatical Goals
My research goals (as stated in my sabbatical proposal) were: (1) to investigate the
effects of strain on graphene nanoribbons; (2) to learn various materials
characterization techniques; (3) high speed optical measurements; (4) fabrication
and manipulation of carbon nanomaterials; (5) application of carbon nanomaterials
to sensors; (6) create a foundation for future research and professional activity in
carbon nanomaterials. At the time of writing the proposal, I had hopes of getting
involved in the use of carbon nanomaterials for energy (i.e. solar cells). The broader
goals, which followed several of the Regents’ priority areas, were as follows:
1. Become introduced to current experimental practice in the field of carbon
nanomaterials.
a. Contribute toward the understanding of charge transfer in carbon
nanotube films, and/or nanopatterned graphene films.
i. Learn the equipment and techniques for producing and
characterizing these carbon nanomaterials.
ii. Apply this knowledge to write a grant proposal for work to be
done at UW-Platteville; submit to U.S. funding agencies.
iii. Apply this knowledge to nanomaterials/engineering education
at UW-Platteville.
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iv. If appropriate, establish an ongoing research collaboration with
the Advanced Materials for Energy and Electronics Group at UWMadison.
2. Instructional collaboration: exchange ideas on teaching and education.
a. Make contacts that may facilitate future access for UW-Platteville
students and faculty at UW-Madison:
i. Materials Science & Engineering department;
ii. Nanoscale Science and Engineering Center;
iii. Materials Research Science and Engineering Center
b. Learn about their educational methods for tools and techniques related
to nanomaterials (for both curriculum and outreach).
3. Instructional impact: incorporate ideas, techniques, skills into at least one
course. Possible courses include Modern Physics, Applied Optics, Sensors Lab,
Engineering Physics Lab, Principles & Applications of Nanotechnology, and
courses still under development for Micro/Nanomaterials program.
4. Continue research to engage students at UW-Platteville, supporting students
enrolled in MSNT 4000, Research in Microsystems & Nanotechnology, and/or
EP 4990, Independent Study in Engineering Physics.
These goals have been largely met, and several are in progress, as discussed below.
Research Goals and Outcomes
Preliminaries
As could probably have been expected, the exact research topic shifted from that of
the proposal. Before my arrival on the UW campus in September 2014, the UW
group developed a need for some more “heads and hands” to deal with Floating
Evaporative Self-Assembly (FESA), an exciting new process by which polymerwrapped, semiconducting carbon nanotubes are dissolved in chloroform (an “ink”)
and deposited onto a silicon surface in an aligned monolayer; that is, the tube-like
carbon nanotubes (CNTs) lie on the surface in a single layer, all lined up with each
other. This was extremely significant, as electrons move much more easily along the
length of a CNT: creating aligned CNT films is a key obstacle to the further
development of carbon nanotube transistors. These promise smaller, faster, and
more energy efficient electronics. Based on their preliminary work, the group had
already created “world-record” thin-film CNT transistors, beating previous bestdesigns by orders of magnitude.
Work done at UW
Despite this success, in September 2014 the process was still not well understood
and was very challenging to replicate. Therefore, my first task was to construct an
experimental apparatus that would allow us to systematically explore the
parameters needed to create these aligned CNT films. I worked with a very friendly
and knowledgeable graduate student, Jerry Brady, and while he trained me on the
FESA process (as well as the purification of semiconducting CNTs from the
commercially-produced “soot” that was our starting material), I designed and built
an apparatus that allowed us to precisely control all of the parameters that were
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known (or thought) to affect the film
deposition. A photo of one iteration of
the apparatus is shown in Figure 1. It
turned out that my “mechanical” skills
were very useful to the group, as well
as my ability to quickly learn Matlab
(last used in my post-doc…) to control
the apparatus. Figure 2 shows the
control panel for the system.
This apparatus was very successful:
the CNT films were reproducible and
large, and we were able to optimize the
deposition process. This led to a long Figure 3. Photo of an early-generation FESA apparatus.
series of experiments during which
we worked to optimize such parameters
as: (1) flow rate of CNT “ink;” (2) distance
between the “ink” needle and the silicon
substrate; (3) size of the needle; (4)
distance between the needle and the water
surface; (5) lift rate of the silicon
substrate. We also used video
microscopes to capture the deposition
process and gain insights. Our efforts
were largely geared toward the
production of large films (inch-square and
beyond) with high uniformity and few
Figure 1. Control screen for the FESA apparatus. We were
defects.
able to run automated experiments that varied the
substrate’s lift rate, and the flow rate of the carbon
We also developed a variation on FESA, nanotube “ink.”
called “continuous FESA,” which used a
continuous flow of the carbon nanotube
“ink” instead of a series of droplets. This
has the potential for smoother deposition,
and led to a patent application by the
Wisconsin Alumni Research Foundation
(WARF), on which I am listed as a coinventor.
I also spent time on an attempt to deposit
(non-aligned) CNTs using a piezoelectric
Figure 2. Scanning electron microscope (SEM) image of
inkjet-style pipettor, which shoots small
aligned carbon nanotube film.
droplets (~100 picoliters) of CNT ink onto
the substrate. Though this was ultimately unsuccessful, I did gain experience in
other methods of depositing CNT films and learned about their characterization.
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This also provided me an opportunity to work with students on other projects, to
get a broader perspective on the research in the group.
After many, many experiments and much analysis, Jerry and I hit upon a good set of
operating parameters that enabled us to deposit aligned films on the order of one
square inch. We sent films to industrial collaborators (who were subsequently able
to produce world-record high-frequency CNT electronics with the goal of mobile
communications), and also made large-format transistors (which truly need large,
continuous films). We also had a better picture of the steps involved in producing
the CNT films – at least at the macroscopic scale.
In May, we had a significant breakthrough – and this has had
significant repercussions for my continued work at UWPlatteville. We learned that FESA – which required a fair bit
of equipment and automation, see Figure 1 – had a simple
model system that would allow us to focus on the “physics”
of the film deposition, which we called “Stationary FESA.” In
short, we had a water droplet resting on a silicon surface;
we would then add droplet(s) of CNT ink onto the water
droplet. The ink would spread over the water, changing the
contact angle between the water and the substrate (see
Figure 4). We discovered that an aligned CNT film was
deposited in the region immediately adjacent to the water
droplet after the contact angle changed with the addition of
the chloroform ink (see Figure 5).
Figure 4. Stationary FESA
process.
Figure 5. Scanning electron microscope image of the CNT deposits left adjacent
to the water droplet (droplet is at the right edge of figure (e)).
This answered several
question we had about
where the deposition
was occurring, and
explained several of the
features we had seen in
our studies. See Figure
5; (f) shows a “coffee
stain,” which is at the
chloroform/air/substrate interface and results in a disordered tangle of CNTs.
Region (g) shows the random deposition at the chloroform/substrate interface.
Region (h), however, shows a small band of aligned CNTs, right at the
chloroform/water/substrate interface. This experiment thus identified both
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another means of depositing aligned CNTs, and showed the location of the critical
region for deposition. Further studies are focusing on this triple interface.
What made this discovery especially exciting for me is that it offers a simple
platform that allows us to study this phenomenon at UW-Platteville. Thus began a
collaboration with the UW group: while they focus on scaling up the FESA process
into “scalable nanomanufacturing,” at UW-Platteville we are able to focus on the
understanding the deposition mechanism and on finding first-principles methods to
improve the quality of the films. Stationary FESA is small and flexible enough that
we can study the effect of a wide range of parameters, including changing the ink,
the substrate, the deposition temperature, the volumes involved, etc. The
collaboration is off to a good start, with eight UW-Platteville students working with
me in the Fall 2015 semester on independent research projects. I continue to
maintain my UW contacts through monthly group meetings in Madison on Friday
afternoons.
Outcomes of the Research
One of my research goals was to make a contribution in the (new-to-me) field of
carbon nanoelectronics and to become better able to perform independent research
in this field. The sabbatical was priceless in this regard; it appears that we have
tapped a potentially rich vein of research with some very promising early results.
I took copious notes of the procedures used for fabricating and testing the devices: I
am certainly better-prepared to do work in this field at UW-Platteville, having
gained direct experience with CNT isolation; Raman mapping of CNT films; SEM
operation; characterization of CNT transistors. Finally, I was able to ‘flex’ some
muscles from my post-doc by building up a Matlab code to control the new
apparatus, and to investigate the application of a piezoelectric “shooter” to our
work.
While I have not yet applied to any external agencies for research support, I have
submitted a proposal to the 2016 Regent Scholars program (UW System), based on
my sabbatical and subsequent Fall 2015 research. My collaborators at UW are
preparing a NSF Scalable Manufacturing grant; if they clear the on-campus
winnowing, I will become part of that proposal, which would support summer
research and several opportunities for Platteville students.
A paper summarizing our current state of knowledge on FESA, including presenting
the large-scale transistor results, is in preparation. I presented a poster at the UWPlatteville Faculty/Staff Research Poster Day this past semester, and plan to give a
seminar in the Spring.
Unfortunately, with the Spring 2015 shelving of the Microsystems and
Nanomaterials (MSNT) major at UW-Platteville, I am unable to fulfill my goals for
“Instructional Collaboration.” Further, the heavy teaching load precipitated by the
budget crisis has caused me to choose between bringing my research into an
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existing course, and developing a research program involving undergraduates. I
chose the latter, and am taking advantage of being “freed” from my MSNT Program
Coordinator duties to focus on providing a wide range of research opportunities for
students who are pursuing the MSNT Minor, or are simply interested in joining a
research project. This is a “new thing” for me, after 17 years at UW-Platteville, and
I’m having a lot of fun.
Sabbatical Opportunitites for UW-Platteville Faculty: Collaboration and Funding
I was very pleased with my sabbatical, and I feel that this could present a model that
could be used by other faculty to overcome typical obstacles to a sabbatical.
I believe that one obstacle is cost; taking half-salary for a year can pose a financial
challenge. Another is family obligations. In my case, I had originally dreamed of
repeating my 2008 trip to the University of Newcastle; however, my children are
now in senior high school and were definitely not interested in missing SAT’s, ACT’s,
a sports season, etc. for a sabbatical. Therefore, I needed to figure out how to have a
good research experience without going far away. (The challenge of simultaneously
paying for a mortgage and a rental combines these first two issues, too.) Finding a
collaborator at UW-Madison allowed me to commute instead of move, thus reducing
the cost and the logistics.
For funding, I was excited to learn about the NSF Research Opportunity Award
(ROA) from my colleague Wei Li (though I don’t know of anyone besides me who
has taken advantage of this). The NSF ROA allows existing NSF award winners to
support faculty from undergraduate institutions. This is generally intended as a
means of supporting research conducted during a summer or a sabbatical. As stated
in the program description, "An ROA is intended to increase or maintain the visitor's
research capability and effectiveness, to improve research and research teaching
capabilities at his or her home institution, and to enhance the impacts and outcomes
of the NSF-funded research of the host principal investigator." I was thus able to
“piggy back” onto an existing grant in Prof. Arnold’s group. Since I didn’t apply until
December 2014, it only provided a few months of support (but was still much
welcomed!).
Another sabbatical challenge, which I learned in 2008, was to sustain the research
effort once I returned to campus. This is really only possible with good research
student – and training them takes time! The ROA award had an additional feature
that I feel was a very important part of continuing my research at UW-Platteville. At
the urging of the NSF Program Officer, I included support for a UW-Platteville
undergraduate to take a REU-type (Research Experience for Undergraduates)
position in the summer of 2015 with the UW group. This student would then be
required to continue the research with me at Platteville for at least the Fall 2015
semester. This allowed me to have someone who could get up to speed on the
project in the Summer, and then in the Fall help establish the research on our
campus and help train other students. I was fortunate to find Chemistry senior
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Kjerstin Gronski, who by all accounts had a rewarding summer in Madison and has
been good to have working with me on campus this semester.
Therefore, this combination of a collaboration with UW-Madison and ROA funding
helped to overcome issues associated with cost, logistics, and continuation of the
work. I’m very happy with how things worked out, and I see this as a path that
could potentially be taken by other faculty at UW-Platteville.
Post-Sabbatical Reflection
Personal
I didn’t have “formal” international travel like I did with my 2008 sabbatical, though
I did take advantage of my free summers in 2014 and 2015 to do some travel that
had professional aspects. In 2014, I traveled to India with my wife for two weeks
while she taught a course; for part of the time I represented our campus and met
with Shanthi Mohan, of EducationUSA in the United States-India Educational
Foundation (USIEF) in Chennai, and pitched UW-Platteville to her (delivered some
materials from Donna Anderson) and answered her questions.
In the summer of 2015, my family followed my wife to Ethiopia, where she worked
with the Family Practice Medical Residency program at Addis Ababa University
(AAU). We lived there for a month and a half, and the kids and I volunteered with a
school serving a particularly poor area (just between the leper colony and the
dump…!). I also represented UW-Platteville by giving two lectures at an AAU
workshop aimed at training instructors in medicine, conducted by the University of
Toronto (INTAPT: Interprofessional Applied Practical Teaching and Learning in the
Health Professions; http://tinyurl.com/hknhc66). My talks were on “Engineering
Education in the U.S.”, which had several parallels with the methods they were
trying to teach the residents, and on “Mentoring.” This was a lot of fun, and my first
time presenting to a non-native-English-speaking audience.
In both countries, I also provided “tech support” for another short course, led by my
wife, on Advanced Life Support in Obstetrics (ALSO; http://tinyurl.com/nezfzdw ).
The scoring spreadsheet I created is now being used by instructors around the
world (!).
Research & Professional
In 2008, I called the University of Newcastle (Australia) sabbatical my best research
experience, ever, anywhere. While I still can’t top the social environment I had
there, professionally, this sabbatical was even better. The work was fun and
rewarding, I learned a lot, and the work is continuing with more undergraduate
researchers than I’d sponsored in the previous several years combined. This
sabbatical truly recharged my batteries, and it’s exciting to be onto yet another
permutation of my career.
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Appendix I: Board of Regents Preferences
and UW System Shared Learning Goals
Board of Regents Preferences and UW System Shared Learning Goals
The Board of Regents has identified several projects are desired components of
sabbaticals for the 2014-2016 academic years. In my original sabbatical proposal, I
identified several as aligned with this proposal. I revisit them here.
Interdisciplinary Activities
I was working with graduate students with backgrounds in Physics, Materials
Science, and Chemistry; I learned techniques that are straight from Physical
Chemistry, and continue to work with a UW-Platteville senior in Chemistry.
Scholarship of Teaching and Learning
According to Kathleen McKinney,1 the authors Martin, Benjamin, Prosser, and
Trigwell2 argue that the scholarship of teaching includes engagement with the
existing knowledge on teaching and learning. While not specifically a SoTL
sabbatical, there was some alignment here:
 while I was unable to apply my new knowledge to the now-defunct
Microsystems & Nanomaterials major, I did pay close attention to how Prof.
Mike Arnold conducted his student research group; this has helped as I work
with a large number of research students on our campus.
Application of Technology to Instruction
When I mentor independent research projects for students, among other things I am
teaching how to perform research and incorporate technology for measurements
and analysis.
In addition, sabbatical proposals are encouraged to take up the teaching and
learning of any of the five UW System Shared Learning Goals. With this proposal,
I expect to be doing most of the “learning,” at least initially, though I expect to be
able to translate much of my learning into student learning.
Knowledge of the Natural World
The CNT research contributed to the knowledge of the fundamental physical
properties of nanomaterials. I expect to incorporate what I learned into my
teaching, so my students will also benefit from this effort.
1
McKinney, K., “What is the Scholarship of Teaching and Learning (SoTL) in Higher
Education?” Retrieved 8/28/2013: sotl.illinoisstate.edu/downloads/pdf/definesotl.pdf.
2
Martin, E., Benjamin, J., Prosser, M., & Trigwell, K. (1999). Scholarship of teaching: A
study of the approaches of academic staff. In C. Rust (Ed.), Improving student learning:
Improving student learning outcomes: Proceedings of the 1998 6th International
Symposium. Oxford: Oxford Centre for Staff and Learning Development.
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Critical and Creative Thinking Skills
By its nature, the fundamental, open-ended research projects described here will
required the use of “inquiry, problem solving, and higher-order qualitative and
quantitative reasoning.” Such is the nature of scientific research. By strengthening
my own skills in this area during the sabbatical, I am now better able to help
students develop their own skills in these areas.
Effective Communication Skills
I presented project updates to the rest of the research group during the sabbatical; I
also presented results of my research at Poster Day and we are presently writing a
paper for a peer-reviewed publication.
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