Contents
What is the main difference between metal semiconductor and insulator?
Metals are good conductors of electricity. Insulators are bad conductors of electricity. Similarly,semiconductor devices are partial conductors of electricity means their conductivity lies between conductors and insulators. In case of metals, electrons fill the conduction band partially.
What is the difference between a metal and a semiconductor in terms of their energy bands?
In insulators the electrons in the valence band are separated by a large gap from the conduction band, in conductors like metals the valence band overlaps the conduction band, and in semiconductors there is a small enough gap between the valence and conduction bands that thermal or other excitations can bridge the gap.
What makes a metal a semiconductor?
Semiconductors are materials which have a conductivity between conductors (generally metals) and nonconductors or insulators (such as most ceramics). Semiconductors can be pure elements, such as silicon or germanium, or compounds such as gallium arsenide or cadmium selenide.
What is difference between metal and conductor?
is that conductor is one who conducts or leads; a guide; a director while metal is any of a number of chemical elements in the periodic table that form a metallic bond with other metal atoms; generally shiny, somewhat malleable and hard, often a conductor of heat and electricity.
How is an N-type semiconductor formed?
An n-type semiconductor results from implanting dopant atoms that have more electrons in their outer (bonding) shell than silicon. The resulting semiconductor crystal contains excess, or free, electrons that are available for conducting current.
What is property of Misch metal?
Misch metal is also used as a deoxidizer in various alloys and to remove oxygen in vacuum tubes. As an alloying agent in magnesium, it contributes to high strength and creep resistance.
How are semiconductors different from metals and insulators?
The band theory of solids provides a clear set of criteria for distinguishing between conductors (metals), insulators and semiconductors. As we have seen, a conductor must posses an upper range of allowed levels that are only partially filled with valence electrons.
How are different types of metal-semiconductor contact formed?
The principle of forming different types of the metal-semiconductor contact is the mismatch of the Fermi energy between metal and semiconductor material, which is due to the difference in work functions. Figure 1 shows the energy band diagram after the contact is made.
Why do electrons keep transferring from semiconductor to metal?
Therefore, electrons will keep transferring between the semiconductor and the metal until the EF is aligned, which would cause a formation of depletion region between the MS contact.
Why is Fermi energy higher in metal than in semiconductor?
The Fermi energy of metal becomes higher than the Fermi energy in the semiconductor, which results an increasing of the barrier potential across the MS junction. The large barrier will block the diffusion of electrons from semiconductor to the metal.