Both semiconductors and superconductors are the two categories of materials that offer conductivity. However, the level of conductivity offered by the two crucially differentiates the two. The significant difference between semiconductors and superconductors is that in the case of semiconductors, the conductivity ranges between conductor and insulator.
As against superconductors are the materials whose level of conduction is very higher than conductors as these materials possess quite high conductivity but at a specific temperature.
Here in this article, we will see other differences between the two using the comparison chart.
Content: Semiconductors Vs Superconductors
|Basis for Comaprison||Semiconductors||Superconductors|
|Basic||These offer lower conductivity than conductors because of offering moderate resistivity.||The conductivity of superconductors is more than conductors due to zero offered resistance.|
|Current rating||It can only handle fixed level of current.||It can withstand very high value of current.|
|Conductivity range||Between conductors and insulators.||Conductivity is beyond conductors.|
|Band Gap||0.25 to 2.5 eV.||Above 2.5 eV.|
|Examples||Germanium, Silicon, etc.||Aluminium, Bismuth, Mercury, etc.|
Definition of Semiconductor
Semiconductors are referred as the materials whose level of conduction is lower than conductors but more than insulators. This means semiconductors are neither good conductors nor good insulators. A pure semiconductor does not possess accurate conductivity, but by the addition of impurity to the pure semiconductor material somewhat greater conductivity is achieved.
The classification of semiconductors is based on the type of impurity-doped to the pure semiconductor to increase its conductivity. The semiconductors are of two types, p-type and n-type semiconductors. Also, with the addition of different types of impurity, the two semiconductors have a different type of majority and minority charge carriers.
Basically, a certain energy gap exists between the conduction band and the valence band. And for the current flow to take place the majority carriers must move from the valence band to the conduction band. This energy level separation is referred as bandgap.
For semiconductors, the bandgap is generally less than 2 eV thus, on gaining a sufficient amount of energy, the electrons move from valence to conduction band and results in the flow of current. With the increase in temperature, more energy is gained by the charged carriers resulting in more conduction and a decrease in resistance.
Definition of Superconductor
The materials that lose all its electrical resistivity below a critical temperature are known as superconductors. This means that below a specific temperature, superconductors allow the flow of current through them without any loss of energy. Thus, it is said that their conductivity at a certain temperature is more than normal conductors. These are regarded as the materials that possess zero resistivity at a certain temperature.
In normal conductors with the increase in temperature, the resistivity increases, so a decrease in temperature reduces the resistance. But at the lowest temperature, the resistivity possesses a specific value. Thus, the materials in which the resistivity suddenly attains zero value at a particular temperature are known as superconductors.
As these hold the ability to carry current with no resistance hence no loss of energy is associated with it.
In superconductivity, pair formation of electrons does not take place, however, highly correlated pairs of electrons exhibit superconductivity. Basically, in superconductors, highly strong interaction between two electrons in the lattice results in a high flow of current below the critical temperature.
Superconductors are mainly classified as Type I and Type II superconductors.
The Type I superconductors act as conductors at room temperature but after reaching critical temperature, the material allows an uninterrupted flow of current. However, the Type II superconductors are not at all good conductors at room temperature but once reaching the critical temperature, it attains superconductivity. Generally, metallic compounds and alloys exhibit superconductivity.
Key Differences Between Semiconductor and Superconductor
- The semiconductors are the materials that possess moderate conductivity. As against, superconductors are the materials that exhibit very high conductivity.
- The band gaps existing between energy levels range between 0.25 to 2.5 eV in the case of semiconductors. While, the bandgap between the energy levels in the case of superconductors is more than 2.5 eV, but diminishes at the critical temperature.
- The current rating of semiconductor material is fixed as semiconductors can not have current more than that specified value. On the contrary, superconductors can withstand a very high amount of current below the critical temperature.
- The conducting range of semiconductors is between conductor and insulator. But the conducting range of superconductors is beyond the conductors.
- Semiconductors consume a moderate amount of energy as the current flowing experience some resistance. While superconductors consume negligible energy and permit very large current flow.
So, from this discussion, we can conclude that semiconductor and superconductor are the two classes of conducting materials that which are mainly categorized according to their level of conductivity.