Semiconductor Physics and Diodes MCQs

Question 1

The term bias means

Accepted Answer

a dc voltage applied across the P-N junction to control its operation

Answer

the ratio of majority carriers to minority carriers

Answer

the amount of current across the P-N junction

Answer

none of the above

Question 2

The forward-bias a P-N junction, diode,

Accepted Answer

a and c above

Answer

an external voltage is applied that is positive at the anode and negative at the cathode

Answer

an external voltage is applied that is negative at the anode and positive at the cathode.

Answer

an external voltage is applied that is positive at the P-region and negative at the N-region

Question 3

When a P-N junction is forward-biased

Accepted Answer

the current is produced by both holes and electrons

Answer

the only current is the hole current

Answer

the only current is the electron current

Answer

the only current is produced by majority carriers

Question 4

A P-N. junction diode's dynamic conductance is directly proportional to

Accepted Answer

the current

Answer

the applied voltage

Answer

the temperature

Answer

the thermal voltate

Question 5

The junction capacitance of a linearly graded junction varies with the applied reverse bias, VR as

Accepted Answer

VR-1"

Answer

VR-1

Answer

VR-1/2

Answer

VR112

Question 6

The diffusion capacitance of a forward biased e N (p+ indicates heavily doped P-region) junction diode with a steady current I depends on

Accepted Answer

mean life-time of electrons

Answer

width of the depletion region

Answer

mean life-time of holes

Answer

junction-area

Question 7

At room temperature of 25?C, the barrier potential for silicon is 0.7 V. Its value at 125?C is___volt.

Accepted Answer

0.9

Answer

0.5

Answer

0.3

Answer

0.7

Question 8

Junction breakdown occurs

Accepted Answer

under reverse bias

Answer

under high temperature condition

Answer

with forward bias

Answer

because of manufacturing defect

Question 9

Avalanche breakdown is primarily dependent on the phenomenon of

Accepted Answer

collision

Answer

doping

Answer

ionization

Answer

recombination