Engineering Physics

Multiple Choice Questions

1. The electrical conductivity of a semiconductor at absolute zero of temperature is:    ( )
   1. finite
   2. very large
   3. zero
   4. none
2. At room temperature, the conduction band electrons are ________ that of valence band holes in an intrinsic semiconductor.    ( )
   1. less than
   2. greater than
   3. equal to
   4. none
3. If m*_h > m*_e, then the position of Fermi energy level is:    ( )
   1. at the centre of energy gap
   2. just above the centre of energy gap
   3. just below conduction band
   4. just above valence band
4. The carrier concentration in an intrinsic semiconductor ________ with increase of temperature.    ( )
   1. increases
   2. decreases
   3. remains same
   4. none
5. Electrical current in an intrinsic semiconductor is due to:    ( )
   1. conduction band electrons
   2. valence band holes ...