By Peter Weiss
The unsung heroes of the microelectronics revolution are impurities intentionally added to semiconducting materials. A sprinkling of such atoms as boron or phosphorus, for example, is pivotal to much of the electronic and optical performance that makes microchips useful.
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Nevertheless, attempts to include such impurities in tiny clumps of atoms known as semiconductor nanocrystals have often failed. A study in the July 7 Nature offers an explanation for this roadblock—and a way around it.