Fermi dirac level, Electrical Engineering

Assignment Help:

Fermi Dirac level:

Sol. The Fermi level is simply a reference energy level. It is the energy level at which the probability of finding an electron n energy unit above it in the conduction band is equal to the probability of finding a hole n energy units below it in the valence band. Very simply, it can be considered to the average energy level of the electrons, as illustrated in fig. (a). For simplification let us assume that (i) widths of energy bands are  small in comparison to forbidden energy gap between them (ii) all levels in a band have the same energy, bandwidths being assumed to be small (iii) energies of all levels in valence band are E0, as shown in fig. (a) and (iv) energies of all levels in conduction band are EG. Let the zero energy reference level be taken arbitrarily at the top of the valence band, as shown in fig. (b). Now number of electrons in conduction band, where P represents the probability of an electron having energy EG. Its value may be determined from Fermi Dirac probability distribution function given as where P (E) is the probability of finding an electron having any particular value of energy E.


Related Discussions:- Fermi dirac level

What is trans conductance, Q. What is Trans conductance? It is ratio of...

Q. What is Trans conductance? It is ratio of small change in drain current to the corresponding change in the gate-to-source voltage for a constant gate-to-source voltage .it i

SINGLE-PHASE INDUCTION MOTORS MOTORS, HOW DOES SINGLE PHASE INDUCTION MOTOR...

HOW DOES SINGLE PHASE INDUCTION MOTORS DEVELOP A STARTING TORQUE ?

Can you show the decimal to octal conversion, Q. Can you show the Decimal t...

Q. Can you show the Decimal to Octal Conversion? To convert decimal to octal is somewhat more difficult. The usual method to convert from decimal to octal is repeated division

Give the properties and application of asbesto, Give the properties and app...

Give the properties and application of asbesto. Asbestos: It is inorganic fibrous material. Two kinds of asbestos are available. Chrysotile asbestos : This material is h

Determine the base current, Q. A transistor has a base current i B = 25 µA...

Q. A transistor has a base current i B = 25 µA, α = 0.985, and negligible ICBO. Find β, iE, and i .

Write short note on common vs associated channel signalling, Q. Write short...

Q. Write short note on Common vs. associated channel signalling. Associated vs. Common channel signalling: Out band signalling suffers from very limited bandwidth. Both a

What is cd-rom, Compact Disc - Read Only Memory. A CD-ROM is any compact di...

Compact Disc - Read Only Memory. A CD-ROM is any compact disc which having computer data. These discs can store enormous amounts of data (up to 640 megabytes). If there is a large

Explain the suitability of aluminium, Explain the suitability of aluminium ...

Explain the suitability of aluminium  that is used as electrical conducting materials. Aluminium : Conductors are appropriate for ambient and very high temperature. Use of alu

What is polyphase induction machine performance, Q. What is Polyphase Induc...

Q. What is Polyphase Induction Machine Performance? Some of the important steady-state performance characteristics of a polyphase induction motor include the variation of curre

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd