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Вопрос 325

Why is gallium arsenide (GaAs) useful for semiconductor devices operating at UHF and higher frequencies?

  1. Higher noise figures
  2. Higher electron mobilityПравильный ответ
  3. Lower junction voltage drop
  4. Lower transconductance

Объяснение

Electrons drift through gallium arsenide several times faster than through silicon for the same electric field, so carriers cross the device in less time and useful gain extends into the UHF and microwave range. GaAs devices also tend toward lower noise figures rather than higher, and it is mobility rather than junction drop or transconductance that buys the frequency.

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Вопрос 325: Why is gallium arsenide (GaAs) useful for semiconductor… · FCC Amateur Extra Class (Element 4) · Questena