Semi-conductors, Physics

Assignment Help:

 

Semiconductor is solid material whose electrical conductivity at room temperature lies between conductivity of a conductor and that of an insulator. At high temperatures its conductivity approaches that of a metal, and at low temperatures it acts as insulators. Every material can be classified as a conductor, an insulator, or a semiconductor. These three distinct classes of material arise from a difference in the structure of the allowed electron energy level. In particular every material possesses both valance and a conduction band for electrons and the energy difference between these two bands will determine how easily an electric current will pass through the material. In semiconductor there is a limited movement of electrons, depending upon the crystal structure of the material used. The substances firstly used for semiconductors were the elements Silicon, germanium and gray tin. It was establish that the incorporation of some impurities in them improves their conductive properties. The property either adds free electrons or creates in holes in the crystals structures of the host substances by attracting electrons. Thus there are two kinds of semiconductors: N-type (negative) in which the current carriers are negative and the P-type, in which the positively charged holes move and carry the current. The process of adding this impurity is called doping, the impurities themselves are called do pants. Certain chemical compounds, including Gallium Arsenide, Indium antimonite, and aluminium phosphate are semiconductors.

 


Related Discussions:- Semi-conductors

Determine the current in the coil and its phase angle, A coil of inductance...

A coil of inductance 159.2mH and resistance 40 is connected in parallel with a 30µF capacitor across a 240V, 50Hz supply. Calculate (a) the current in the coil and its phase ang

Explain variable or non-uniform velocity, VARIABLE OR NON-UNIFORM VELOCITY:...

VARIABLE OR NON-UNIFORM VELOCITY: If a body covers unequal displacement in most equal intervals of time, though the smallest interval may be, then the velocity of the body is s

Moment of inertia of rigid bodies, Moment of Inertia of Rigid Bodies : For ...

Moment of Inertia of Rigid Bodies : For a continuous mass distribution like found in a hard object, we remove the summation of Eq. (ii) by an integral. If the object is separated i

What is joule cycle, What is Joule Cycle? Find the efficiency of the J...

What is Joule Cycle? Find the efficiency of the Joule cycle, consisting of two isobars and two adiabats.  Presume that the heat capacities of the gas C p and C v are constan

Find the electric potential, Q. Find the electric potential at a distance 0...

Q. Find the electric potential at a distance 0.09 m from a charge of 4 X 10 -7 C. The electric potential V = ( 1/4πεo ) q /r = ( 9 X 10 9 X 4 X 10 -7 )/ 9 X 10 -2 = 4 X 10

Explain single force vector, For any single force vector, there is only one...

For any single force vector, there is only one angle for which its x- and y-components are equal in size. a. What is that angle? b. How many times bigger is a vector at this

Unit of impulse, UNIT: SI unit of impulse is NS (Newton x Second) or ...

UNIT: SI unit of impulse is NS (Newton x Second) or kgms -1

Explain extrusion, Extrusion: It is a metal working process that makes lon...

Extrusion: It is a metal working process that makes long lengths of uniform cross sectional area from a metal billet by causing the latter to flow under hydrostatic pressure by a

Draw a free-body diagram for the elevator, Erika is on an elevator and pre...

Erika is on an elevator and presses the button to go down. When the elevator first begins moving, it has an acceleration of 2.5 m/s 2 downward. Erika and the elevator have

Path of the magnetic field produced by the wire, Question: The external...

Question: The external surface of a short vertical segment of plastic pipe is hidden from view by wire wrapped around the pipe. Current flows clockwise as out looked from above

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