Band theory of solids, a brief introduction - class-XII
Description: band theory of solids, a brief introduction | |
Number of Questions: 63 | |
Created by: Palash Sundaram | |
Tags: semiconductor electronics: materials, devices and simple circuits electronic devices physics quantum physics semiconductors |
Carbon, silicon and germanium have four valence electrons each. These are characterised by valence and conduction bands separated by energy band gap respectively equal to $(E _g) _C,\, (E _g) _{Si}$ and $(E _g) _{Ge}$.Which of the following statements is true?
The band gap is larger for which of the following
The electrical conductivity of a semiconductor increases when electromagnetic radiation of wavelength shorter than $2480\ nm$ is incident on it. The band gap in $(eV)$ for the semiconductor is.
The difference between the highest energy in a band and lowest energy in the next higher band is called the band gap between the two energy bands.
In extrinsic semiconductors :
Among the following, the wrong statement in the case of semiconductor is:
At absolute zero, Si acts as
What is the resistivity of a pure semiconductor at absolute zero ?
Which one is the weakest type of bonding in solids ?
The intrinsic semi conductor becomes an insulator at
Bands in solids are formed due to a group of closely spaced ________ .
The energy gap in glass at room temperature is :
A pure germanium crystal at absolute zero is :
A pure semiconductor at absolute zero has :
The band structure determines the _________ behaviour of a solid.
In insulators (CB is conduction band and VB is valence band)
The energy gap in a semiconductor
When the band gap for a semiconductor is low
Which of the following has least band gap energy at $273K$.
What is the optimum band gap energy for a material to be considered as a semiconductor?
Choose the correct statement(s):
Which among the following having highest band gap ?
What is the energy band gap of silicon and germanium respectively in $eV$ ?
Which of the following statement(s) is/are correct
At what temperature semiconductors behaves as an ideal insulator?
What is an energy gap?
Fermi energy level for $p-type$ extrinsic semiconductors lies
Energy gap of conductor is
Fermi energy level for intrinsic semiconductors lies
Energy gap of semiconductor is approx
The level formed due to impurity atom, in the forbidden energy gap, very near to the valence band in a P-type semiconductor is called
At absolute zero temperature a semiconductor behaves like :
The band gaps of a conductor, semiconductor and insulator are respectively ${Eg} _{1}, {Eg} _{2}$ and ${Eg} _{3}$. The relationship between them can be given as.
Energy gap in case of Germanium is about
The energy gap is highest in the case of
At absolute zero, a semiconductor is an insulator because _________.
With rise in temperature the resistance of germanium,
The energy bands are present only when the substance is present in the solid state.
The energy gap $E _G$ of a semi-conductor decreases with rise in temperature.
With rise in temperature, resistance of a semiconductor material (germanium or silicon)
The forbidden gap for a pure silicon at the room temperature is _______eV.
A pure germanium crystal at absolute zero is:
State whether True or False :
What is forbidden energy gap(Eg) or band gap?
Give band gap Eg value for conductor, insulator and semiconductor?
The electrical conductivity of a semiconductor increases when electromagnetic radiation of wavelength shorter than $2480nm$ is incident on it The forbidden band gap for the semiconductor is
In germanium crystal, the forbidden energy gap in joule is:
The energy of radiation emitted by $LED$ is :
Given that the mobility of electrons in Ge is $0.4$ metre square/volt sec and electronic charge is $ 1.6 \times 10^{-19}$C. How many door atom (per $ m^3$) have in semiconductor of conductivity $500$ mho/m:-
Three semiconductors are arranged in the increasing order of their energy gap as follows: the correct arrangement is
Depletion layer consists of:
The band gap for a pure semi-colour is $2.1\ eV$. The maximum wavelength of a photon which is able to create a hole-electron pair is:
State whether true or false:
The highest occupied energy band is called ________ and lowest unoccupied energy band is called the _________ .
In metals, the conduction bands are incompletely filled orbitals that allow electrons to flow.
The highest energy band which is filled at zero Kelvin is called ________.
If the energy gap of a semiconductor is 1.1 e V it would be:
Which of the following statement(s) is/are correct:
Fill in the blank.
Energy band gap size for insulators is in the range ________ eV.
In the bandgap between valence band and conduction band in a material is $5.0eV$, then the material is
The electrical conductivity of a semiconductor increases when radiation of the wavelength shorter than $2480nm$ is incident on it.The bandgap (in eV) for the semiconductor is
State whether given statement is True or False
The probability of electrons to be found in the conduction band of an intrinsic semiconductor at a finite temperature decreases exponentially with increasing bandgap.