Semiconductor Material

IMPORTANT

Semiconductor Material: Overview

This topic covers concepts such as Conduction Band and Valence Band in Semiconductors, Current Carriers, Electrons and Holes, Intrinsic Semiconductor, Electrical Conductivity of Intrinsic Semiconductor, etc.

Important Questions on Semiconductor Material

EASY
IMPORTANT

In a pure semiconductor, electric current is due to_________.

EASY
IMPORTANT

In a p–type semiconductor, the concentration of holes is2 × 1015 cm-3  The intrinsic carrier concentration is2 × 1010 cm-3 . The concentration of electrons will be.

MEDIUM
IMPORTANT

Assertion : An n-type semiconductor has a large number of electrons but still it is electrically neutral.

 Reason : An n-type semiconductor is obtained by doping an intrinsic semiconductor with a pentavalent impurity. 

EASY
IMPORTANT

How current is conducted in intrinsic semiconductor?

EASY
IMPORTANT

In an intrinsic semiconductor, the number of free electrons equals the number of holes.

EASY
IMPORTANT

The probability of electrons to be found in the conduction band of an intrinsic semiconductor at finite temperature is which of the following?

MEDIUM
IMPORTANT

The mobility of free electrons is greater than that of free holes because

HARD
IMPORTANT

Describe the conduction band and valence band in semiconductors.

EASY
IMPORTANT

Define electron motion in a semiconductor.

EASY
IMPORTANT

The truth table of a logic gate is given as

Input Output
1 0
0 1

What is the gate?

EASY
IMPORTANT

The probability of electrons to be found in the conduction band of an intrinsic semi-conductor at a finite temperature

EASY
IMPORTANT

Explain the electric current due to electrons in an intrinsic semiconductor.

EASY
IMPORTANT

For p-type semiconductors, Holes are majority carriers and trivalent atoms are the dopants.

EASY
IMPORTANT

At absolute zero temperature, intrinsic Germanium and intrinsic Silicon are

HARD
IMPORTANT

Calculate the electric current generated in an intrinsic germanium plate at room temperature whose area is 2×10-4 m2 and width is 1.2×10-3 m and a potential difference of 5 V is applied across its faces. Intrinsic charge carrier density is 1.6×106/m3 for germanium at room temperature. The mobility of electrons and holes is 0.4 m2V-1s-1 and 0.2 m2V-1s-1.

EASY
IMPORTANT

At absolute zero temperature intrinsic Germanium and intrinsic Silicon, are

EASY
IMPORTANT

Distinguish between intrinsic and extrinsic semiconductors.

EASY
IMPORTANT

Explain the behaviour of an intrinsic semiconductor at absolute zero temperature and at room temperature.

EASY
IMPORTANT

Define intrinsic semiconductor and extrinsic semiconductor.