Semiconductor Physics and Diodes MCQs

Question 1

Most commonly employed pentavalent impurities are

Accepted Answer

Arsenic, Antimony

Answer

Boron, Indium

Answer

Aluminium, Antimony

Answer

Arsenic, Indium

Question 2

A P-type semiconductor material is formed by adding to the semiconductor controlled amounts of

Accepted Answer

some trivalent impurity

Answer

Some pentavalent impurity

Answer

arsenic

Answer

none of these

Question 3

Referring to the energy level diagram of semiconductor materials, the width of forbidden gap is

Accepted Answer

about 1 eV

Answer

about 10 eV

Answer

about 100 Ev

Answer

about 0.1 eV

Question 4

A P-type semiconductor material as a whole is

Accepted Answer

electrically neutral

Answer

positively charged

Answer

negatively charged

Answer

none of these

Question 5

An N-type semiconductor material as a whole is

Accepted Answer

electrically neutral

Answer

positively charged

Answer

negatively charged

Answer

none of these

Question 6

One of the following statements justifies the extensive use of semiconductor materials.

Accepted Answer

It is because of the fact that they exhibit some wide ranging characteristics when certain specific impurities are added to them in controlled amounts

Answer

It is because of their low forbidden energy gap

Answer

It is because of their resistance value which lies between that of good conductors and insulator

Answer

It is because of ease of fabrication of semiconductor material into practical active and passive devices

Question 7

Pick the odd-man out (referring to the material used for their fabrication

Accepted Answer

fixed resistors

Answer

thermistors

Answer

sensistors

Answer

varistors

Question 8

A semiconductor is said to be in thermal equilibrium with its environment if

Accepted Answer

for any process, there is a reverse process that occurs at the same rate

Answer

its characteristics remain unaltered with charge in device temperature

Answer

its characteristics do not change with temperature

Answer

the device temperature is equal to environmental temperature

Question 9

Typical value of forbidden energy gap in germanium is

Accepted Answer

0.67 eV

Answer

1 eV

Answer

1.4 eV

Answer

10 eV