| When Brooks Hitt talks about his career, his listeners usually request
elaboration. "People always ask you what you do and, unfortunately,
ellipsometer is not a household word yet," chuckled the technical
specialist with J. A. Woollam Company in Lincoln, Nebraska. However,
Mr. Hitt doesn't have any problem explaining the significance of the
ellipsometer to companies such as Motorola or Texas Instruments. At
the age of 25, Mr. Hitt applies his knowledge of physics to provide
an invaluable service to the burgeoning computer industry.
J. A. Woollam Company is the worldwide leading producer of spectroscopic
ellipsometers, an important tool for measuring the quality of semiconductors.
Semiconductors, made from materials such as silicon, operate like
microscopic switches in computers. To operate effectively, the semiconductor
must be constructed to precise detail. Imperfections frequently
emerge in the manufacturing process. One way to check for such errors
is to measure a semiconductor's optical properties. The spectroscopic
ellipsometer uses polarized light to measure optical characteristics
such as index of refraction and thickness of the material. After
reflecting off the semiconductor, the polarization of the light
changes. The change in polarization reveals the semiconductor's
properties. A high quality ellipsometer can identify discrepancies
of one angstrom, the equivalent of .0000000001 meters.
Mr. Hitt builds the monochromator, which serves as the light source
for the ellipsometers. The monochromator obtains its name from monochromatic,
meaning light consisting of only one wavelength. The unique design
of each monochromator requires individual construction. The monochromator
projects light from a xenon arc lamp through a series of slits and
mirrors in order to concentrate the beam prior to entering the polarizer.
When not completing a customer order, Mr. Hitt researches design
improvements for the monochromator. Mr. Hitt's physics background
empowers his creativity. "I enjoy the freedom I have to test
new ideas," he said.
Of course, not every new idea works. A few years ago, J.A. Woollam
employees sought to increase the wattage of the arc lamp. This would
have improved the machine's precision. However, the increased wattage
generated heat, creating a need for a water-cooling system. The
designers quickly recognized that this would lead to unacceptable
expenses.
Although frustrating, the failures are as much apart of the scientific
method as the successes. As an undergraduate at UNL, Mr. Hitt worked
as a research assistant to Dr. Tim Gay. The experience taught him
the "trial and error" mindset of science. "If you
have an idea, the only way to see if it's a good idea is to devise
an experiment, test that idea, and see if it works," Mr. Hitt
explained. Of course, after a few disappointments, "It's especially
rewarding when your idea turns out to be useful and will improve
the product."
Mr. Hitt also enjoys intellectual exchanges with other members
of the physics community. As a physics major at UNL, Mr. Hitt benefited
from small class sizes and individualized instructor attention.
A similar environment exists at J. A. Woollam. "The thing that
I have always enjoyed about working with science is the discussions
that you have with your co-workers. It's fulfilling in the respect
that I am continually learning, and hopefully, others are learning
from me as well," Mr. Hitt explained. |
