Electronic Devices and Circuits - Engineering

Q1:

Which of the following elements act as donor impurities?
  1. Gold
  2. Phosphorus
  3. Boron
  4. Antimony
  5. Arsenic
  6. Indium
Select the answer using the following codes :

A 1, 2 and 3

B 1, 2, 4, and 6

C 3, 4, 5 and 6

D 2, 4 and 5

ANS:D - 2, 4 and 5

Only antimony, arsenic and phosphorous are pentavalent.