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NEWS
Thursday, May 25, 2017
The Michigan Daily — michigandaily.com
University chemists discover environmentally
friendly method for creating semiconductor films
Team finds cheaper
method of making
component of nearly
all electronic devices
By COLIN BERESFORD
Daily Staff Reporter
A team of chemists at the Uni-
versity of Michigan have devel-
oped a new method to create
single-crystalline semiconductor
films, a component of nearly all
electronic devices. The team, led
by Stephen Maldonado, associate
professor of chemistry, invented
a more environmentally-friendly
and cheaper method to create
semiconductor films.
Semiconductors are used to
create lasers and LEDs due to the
light they emit when they contain
impurities, according to the web-
site of the University of Mary-
land’s School of Engineering.
They are also used to fabricate
solar cells because of their ability
to absorb light and generate a cur-
rent.
The process discovered by the
University of Michigan chem-
ists doesn’t use excess heat and
doesn’t require the use of hazard-
ous gas. Instead, the team uses
water at room temperature and
easy-to-make equipment to cre-
ate the crystalline semiconductor
films.
In
an
email,
Maldonado
detailed what inspired him and
his group to develop this new
method for creating semiconduc-
tors — emphasizing their interest
in discovering “greener ways to do
useful chemistry.”
“But another pertinent moti-
vation for this particular work
is a desire to build upon a simple
finding we came across several
years ago,” Maldonado wrote.
“We discovered serendipitously
liquid metals are useful sol-
vents for semiconductor crystal
growth even at room temperature.
Accordingly, we have been really
motivated to push this concept
as far as possible, both for large
materials (this work) and nano-
materials (other works of ours).”
The method is more environ-
mentally friendly due to the lack
of heat and hazardous gases.
“If you don’t have to input ener-
gy to generate high temperatures,
low vacuums, or reactive precur-
sor molecules (gases), the energy
cost and potential environmental
impact of the process are nec-
essarily
lowered,”
Maldonado
wrote.
Rackham student Daniel Bier, a
student in the Erb institute, wrote
in an email to the Daily he would
want to reserve judgement on how
much greener the newly devel-
oped method is, considering the
number of factors that can affect
the environmental impact of this
technology.
“It’s easy to say that something
is green, but to evaluate how
much ‘greener’ this technology
is, you should consider how this
new approach will impact energy
and material consumption across
the supply chain,” he wrote.
“This includes the environmental
impact of purchasing new capital
equipment to build the chips and
the amount of energy and raw
ZOEY HOLMSTROM/Daily
Trump speaks at a rally during his 2016 Presidential campaign.
materials involved in manufactur-
ing.”
Bier also said the change in
impact could be very small and by
making electronics cheaper, more
could be thrown away.
“The biggest question for me is
how ‘material’ is this new technol-
ogy from an environmental per-
spective: is the change in energy or
material use significant, or just a
few percentage points?” he wrote.
“Would this make producing elec-
tronics so much cheaper that overall
manufacturing volumes skyrocket,
leading to devices becoming more
disposable and ending up in land-
fills?”
How this discovery will change
how semiconductors are created
in the future and on a large scale
is largely unknown, but has the
potential to create waves in the
electronics industry, Maldonado
said.
“What we developed in our lab
is properly best thought of as a pro-
totype,” Maldonado wrote. “We
are (predominantly) not engineers
in my group, so we have not been
focused on the challenges of scale
or designing a fabrication assembly
line.”
The finding is incredibly impor-
tant in respect to how different it is
from the traditional way to produce
semiconductor films, Maldonado
said. While the method needs more
work, it has shown what is possible.
“I think they (the findings) are
important because they demon-
strate a radically different way
to make useful materials,” Mal-
donado said. “Basically, we use
electrical energy to drive crys-
tallization rather than thermal
energy. This work shows that
with this concept you can take a
raw oxidized source and directly
convert it into a highly crystal-
line semiconductor. By playing
with aspects of the system, we
have shown that we can control
exactly where and how crystal-
lization occurs.”
Maldonado is optimistic about
the progress his team has made
so far.
“We’re not there yet, but we’re
a lot closer than I thought we
would ever be before we started
this work.”
this very topic in recent months.
Sanchez-Ronquillo,
who
is
a
father of two, was acquitted from
deportation in 2014 but detained
again in April after requesting
a stay, sparking protests from
the Ann Arbor community. On
Tuesday,
community
action
resulted in a federal judge’s
decision to delay the deportation.
Commissioner Conan Smith,
who introduced the resolutions,
said community mobilization has
been crucial in work on the topic.
However, support for these
resolutions and others like them
have not been uniform.
During public hearing before
the
initial
vote,
Northfield
Township Trustee Tawn Beliger
said placing the interests of the
undocumented
was
grounds
for recalling an elected official,
adding
that
taxpayer
money
would be better spent on fixing
roads, as reported by MLive.
Additionally, the resolutions
have been framed in response
to actions of President Donald
Trump’s
administration
—
the resolution which calls on
Congress to restrict deportations
mentions the President explicitly
— which may be disagreeable to
those who voted for him in the
2016 elections and support his
policies. In Washtenaw County,
this amounts to 26.5 percent of
those who voted.
Still, advocates maintain that
making Washtenaw County a
welcoming environment in such
trying times is a worthy cause.
Margaret Rapai, an LSA senior
and incoming president of the
Michigan
Refugee
Assistance
Program — which volunteers,
advocates
and
educates
on
refugee issues — said such
policies are important to ensuring
the United States stays a place of
hope for immigrants. MRAP is not
specifically involved with support
for undocumented residents, but
according to Rapai, the goals of
the resolutions are in line with
theirs by creating communal
support for newcomers.
IMMIGRATION
From Page 1
as a loss, seeing as the program
has been deemed inefficient.
“A large portion of this budget
cut comes from the reduction
of the Supplemental Education
Opportunity Grant, an outdated
program
that
gives
money
directly to colleges as opposed
to low-income students,” he said
in a March interview.
Cuts have also been made
to the TRIO and GEAR UP
programs,
which
serve
to
support
low-income
students
and those from disadvantaged
backgrounds.
Seeing
as
the
University has come under fire
for low rates of socioeconomic
diversity, LSA senior Rowan
Conybeare,
chair
of
the
University’s chapter of College
Democrats, said in a March
interview
the
University’s
diversity
will
be
damaged
without these programs.
TRUMP
From Page 1
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