Basic Electronics

What is the primary characteristic of the energy band in a conductor?

• Large energy gap between the valence and conduction bands

• Overlapping of valence and conduction bands

• Completely filled conduction band

• No valence band

In an insulator, the energy gap between the valence band and the conduction band is typically:

• Less than 1 eV

• 1-3 eV

• Greater than 5 eV

• Overlapping

What is the energy band gap of an intrinsic semiconductor like silicon?

• 0.3 eV

• 1.1 eV

• 2.5 eV

• 4 eV

What is thermal generation in semiconductors?

• Creation of free electrons and holes due to heating

• Removal of free electrons by cooling

• Adding impurities to the semiconductor

• Forming a p-n junction

Doping a semiconductor involves:

• Removing electrons

• Adding impurities to modify conductivity

• Increasing the energy band gap

• Cooling the material

What type of impurity is added to create an n-type semiconductor?

• Trivalent

• Pentavalent

• Tetravalent

• None of the above

In a p-type semiconductor, the majority carriers are:

• Electrons

• Holes

• Both electrons and holes equally

• None of the above

In an intrinsic semiconductor, the majority carriers are:

• Electrons

• Holes

• Equal number of electrons and holes

• None of the above

The region around a PN junction that is devoid of free charge carriers is called the:

• Conduction region

• Depletion region

• Active region

• Saturation region

The potential barrier in a PN junction is caused by:

• External voltage applied

• Drift current alone

• Immobile ions on either side of the junction

• Random thermal motion