Semiconductor Physics and Diodes MCQs

Question 1

In a P-type semiconductor, free electrons

Accepted Answer

form minority carriers

Answer

form majority carriers

Answer

take no part in conduction

Answer

equal the number of holes

Question 2

In an unbiased P-N junction, thickness of depletion layer is of the order of

Accepted Answer

0.5 gm

Answer

0.005 gm

Answer

5 gm

Answer

10-1" m

Question 3

A tunnel diode

Accepted Answer

is a highly-doped P-N junction device

Answer

has a small tunnel in its junction

Answer

is a point contact diode with a high reverse resistance

Answer

is a gallium arsenide device

Question 4

When used in a power supply, the function of a Zener diode is to maintain a constant

Accepted Answer

output voltage

Answer

input voltage

Answer

output current irrespective of the load resistance

Answer

supply current

Question 5

A step-recovery diode

Accepted Answer

is mainly used as a harmonic generator

Answer

has an extremely short recovery time

Answer

conducts equally well in both directions

Answer

is an ideal rectifier of high frequency signals.

Question 6

A semiconductor is

Accepted Answer

a material whose conductivity is somewhere between that of a conductor and an insulator

Answer

anothername for a transistor or a diode

Answer

characterized by a very large opposition to the flow of electrical current

Answer

a material used for making bipolar Transistor, Unij unction transistor, Field-effect transistors etc.

Question 7

Doping of semiconductors is

Accepted Answer

the process of adding certain impurities to the semiconductor material in controlled amounts

Answer

the process of purifying semiconductor materials

Answer

the process of converting semiconductor material into some from of active device like BJT, FET, UJT ect.

Answer

one of the steps used in fabrication of ICs

Question 8

An N-type semiconducting material is formed by adding

Accepted Answer

some pentavalent impurity to the semiconductor material

Answer

some trivalent impurity to the semiconductor material

Answer

either of the two impurities mentioned above

Answer

none of these

Question 9

Most commonly employed trivalent impurities are

Accepted Answer

Boron, Indium

Answer

Arsenic, Antimony

Answer

Boron, Arsenic

Answer

Indium, Antimony