Esther Conwell and the computer age

In November 2002, Discover magazine published its list of “The 50 Most Important Women in Science”. Included was Esther Conwell, an American professor of chemistry at the University of Rochester, in New York.

In a career packed with achievements, the magazine settles on one in particular. “Half a century ago,” it says, “Conwell’s research on how electrons course through silicon and other semiconducting materials jump-started the computer age.”

Born in New York City on 23 May 1922, Conwell held four patents and published more than 200 papers. She was a Life Fellow of the Institute of Electrical and Electronics Engineers and of the American Physical Society. She was elected to the National Academy of Engineering, the National Academy of Sciences, and the American Academy of Arts and Sciences. 

In 2010, US president Barack Obama awarded her the National Medal of Science. 

Conwell earned an MS in physics from the University of Rochester, New York, in 1945, and a PhD, also in physics from the University of Chicago in 1948. 

Despite the impressive resume, a 2011 article in UChicago, the University of Chicago Magazine, notes that Conwell “didn’t hold a university research job until late in her career, joining the University of Rochester’s chemistry and physics departments in 1990”. 

Conwell told the UChicago interviewer: she never seriously applied for a good university job because she figured that, as a woman in science, “they wouldn’t consider me”. 

Most of her professional career was spent doing industrial research for companies such as AT&T Bell Labs, GTE Laboratories, and Xerox, which she felt were more welcoming than academia. “It was just between me and the research, how well I did, and how well I felt about myself,” she told UChicago.

Working at the University of Rochester with her thesis adviser, Victor Weisskopf, Conwell began to study how electrons move in semiconducting materials such as silicon. What became known as the Conwell-Weisskopf theory describes how “impurity ions” impede the flow of electrons; it is now considered essential for understanding how different materials affect the flow of electrons inside transistors, and it led to a better understanding of the making of integrated circuits.

The theory, and Conwell’s master’s thesis, were classified during World War II, and only made public in 1945. 

Conwell joined the University of Rochester as an adjunct professor in 1990, becoming a full-time professor in the Department of Chemistry after her retirement from Xerox in 1998.

In her 80s, her next area of study was the movement of electrical charges through DNA. “The motion of charge in DNA can lead to mutations that can be cancer producing,” she said in a 2010 university newsletter. “And the properties of DNA could be useful in assembling circuit elements in nano-electronic circuits.”

Conwell died on 16 November 2014. It was reported in her local newspaper that she was walking near her home when she was struck by a car driven by a neighbour.

The Democrat & Chronicle noted that Conwell was no longer teaching courses at Rochester but that she continued to work “almost daily on campus and was considered a mentor by students and fellow faculty members”. 

Todd Krauss, chairman of the university’s chemistry department, told the newspaper, “She was driven by her science. It really was at her core, her soul. She was all about discovery.”