In late 1948,
shortly after Bell Telephone Laboratories had announced
the invention of the transistor, surprising reports
began coming in from Europe. Two physicists from the
German radar program, Herbert Mataré and Heinrich
Welker, claimed to have invented a strikingly similar
semiconductor device, which they called the transistron,
while working at a Westinghouse subsidiary in Paris.
The resemblance between the two awkward contraptions
was uncanny. In fact, they were almost identical! Just
like the revolutionary Bell Labs device, dubbed the
point-contact transistor, the transistron featured two
closely spaced metal points poking into the surface of a
narrow germanium sliver. The news from Paris was
particularly troubling at Bell Labs, for its initial
attempts to manufacture such a delicate gizmo were then
running into severe difficulties with noise, stability,
and uniformity.
So in May 1949, Bell Labs researcher Alan Holden made
a sortie to Paris while visiting England, to snoop
around the city and see the purported invention for
himself. "This business of the French transistors would
be hard to unravel, i.e., whether they developed them
independently," he confided in a 14 May letter to
William B. Shockley, leader of the Bell Labs solid-state
physics group. "As we arrived, they were transmitting to
a little portable radio receiver outdoors from a
transmitter indoors, which they said was modulated by a
transistor."
Four days later, France's Secretary of Postes,
Télégraphes et Téléphones (PTT), the ministry funding
Mataré and Welker's research, announced the invention of
the transistron to the French press, lauding the pair's
achievement as a "brilliante réalisation de
la recherche française." Only four years
after World War II had ended in Europe, a shining
technological phoenix had miraculously risen from the
still-smoldering ashes of the devastation.
"This PTT bunch in Paris seems very good to me,"
Holden candidly admitted in his letter. "They have
little groups in all sorts of rat holes, farm houses,
cheese factories, and jails in the Paris suburbs. They
are all young and eager." And one of these small,
aggressive research groups, holed up in a converted
house in the nearby village of Aulnay-sous-Bois, had
apparently come through spectacularly with what might
well be the invention of the century—a semiconducting
device that would spawn a massive new global industry of
incalculable value. Or had it?
As was true for the Bell
Labs transistor, invented by John Bardeen
and Walter H. Brattain in December 1947, the technology
that led to the transistron emerged from wartime
research on semiconductor materials, which were sorely
needed in radar receivers. In the European case, it was
the German radar program that spawned the invention.
Both Mataré and Welker played crucial roles in this
crash R&D program, working at different ends of the
war-torn country.
Mataré [see photo in "Transistor Twin"], who
shared his remembrances from his home in Malibu, Calif.,
joined the German research effort in September 1939,
just as Hitler's mighty army rumbled across Poland.
Having received the equivalent of a master's degree in
applied physics from Aachen Technical University, he
began doing radar research at Telefunken AG's labs in
Berlin. There he developed techniques to suppress noise
in superheterodyne mixers, which convert the
high-frequency radar signals rebounding from radar
targets into lower-frequency signals that can be
manipulated more easily in electronic circuits. Based on
this research, published in 1942, Mataré earned his
doctorate from the Technical University of Berlin.
At the time, German radar systems operated at
wavelengths as short as half a meter. But the systems
could not work at shorter wavelengths, which would have
been better able to discern smaller targets, like enemy
aircraft. The problem was that the vacuum-tube diodes
that rectified current in the early radar receivers
could not function at the high frequencies involved.
Their dimensions—especially the gap between the diode's
anode and cathode—were too large to cope with
ultrashort, high-frequency waves. As a possible
substitute, Mataré began experimenting on his own with
solid-state crystal rectifiers similar to the
"cat's-whisker" detectors he had tinkered with as a
teenager.