From Gary Shorthouse
Harwell, Oxfordshire
Roger Allan’s excellent account of the role of silicon carbide in
high-temperature electronics
(“Crystal powers”, 14 June, p 34) is very welcome,
particularly in indicating many of the ways in which the rapid advance of
high-temperature electronics will lead to a safer, more efficient and cleaner
world.
However, the article is misleading in one respect—the status of silicon
as a high-temperature semiconductor. While it is true that most silicon chips
are not specified for operation at temperatures above 125 °C, this is a result
of old military specifications and not a fundamental property of silicon. The
reality is that silicon can be used at temperatures as high as 250 °C. This is
important, as the majority of high-temperature electronic applications are
expected to be within the 125 °C to 250 °C range for at least the next decade,
and the cost of silicon semiconductors is currently only a fraction of that of
silicon carbide. For higher temperatures, wide band-gap semiconductors such as
silicon carbide are still required.
Readers can find a considerable amount of information on this and other
topics in high-temperature electronics at http://www.hiten.com.
Advertisement
