Regarding semiconductors where is fermi level(http://en.wikipedia.org/wiki/Fermi_level )located in an intrinsic,p type,n type semiconductors and why? In an intrinsic semiconductor, n = p. If we use the band-symmetry approximation, which assumes that there are equal number of states in equal-sized energy bands at the edges of the conduction and valence bands, n = p implies that there is an equal chance of finding an electron at the conduction band edge as there is of finding a hole at the valence band edge: f(EC) = 1 − f(EV ) For an n-type semiconductor, there are more electrons in the conduction band than there are holes in the valence band. This also implies that the probability of finding an electron near the conduction band edge is larger than the probability of finding a hole at the valence band edge. Therefore, the Fermi level is closer to the conduction band in an n-type semiconductor. n − type : f(EC) > (1 − f(EV )) ) |EC − EF | < |EF − EV | ) EF > Ei (13) For a p-type semiconductor, there are more holes in the valence band than there are electrons in the conduction band. This also implies that the probability of finding an electron near the conduction band edge is smaller than the probability of finding a hole at the valence band edge. Therefore, the Fermi level is closer to the valence band in an n-type semiconductor. p − type : f(EC) < (1 − f(EV )) ) |EC − EF | > |EF − EV | ) EF < Ei Please visit spam removed for more information like this in our articles and support section.
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