Semiconductor resistivity

In this post we discuss semiconductor resistivity, we know resistivity is the opposing property shown by a material, which depends on two different quantities such as length and cross-section area of the material.

R = ρ (L/A)

In the case of semiconductor resistivity, the same sort of material properties will be there to make changes in resistivity. A semiconductor is a special type of material, which had an intermediate position between conductors and insulators.

Semiconductor resistivity range

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The semiconductor has fewer free chargers than the conductor, it had the property that makes the number of free charges depend strongly on the type and amount id impurities in the semiconductor.

• This is because, at the semiconductor, the gap between the conduction band and the valance band is smaller.

And the range of resistivity at the semiconductor will be measured in the unit Ohm cm.

But the semiconductor resistivity is not limited to one type, we categorize the semiconductor in two doped semiconductors and undoped semiconductors.

• At doped semiconductor = 10-4 ohm-cm is the resistivity range
• An undoped semiconductor or intrinsic semiconductor = 103 ohm-cm is the resistivity range.

Semiconductor resistivity vs temperature

• At zero temperature, the valence band gap is filled and the conduction is empty.
• And when the temperature increases at the semiconductor, it will result in a decrease in the gap between the valence band and conduction band.
• This will be happening by the electrons moves from the valence band, the free electrons releases from the covalent bonds at semiconductor, this will happened due to temperature rise.

Doped semiconductor resistivity vs temperature

• The doped semiconductor will be made with undoped semiconductor, by adding the impurities.
• The semiconductor material is used in electronics to make the electronic component.
• The semiconductors work as an electronic component when energy is applied to it, the electrons start moving and it will come up to conduction band.
• The resistivity at doped semiconductor and temperature will be very much related because a good doped semiconductor means, they may be better at dealing with the temperature.
• Silicon and germanium are the common doped semiconductors, silicon is much better with higher temperatures.