Skip to main content

N-type semiconductor

The extrinsic n Type Semiconductor is formed, when a pentavalent impurity is added to a pure silicon or germanium atom in small amount and as result large number of electrons are created in it.

A pentavalent impurity like phosphorous, arsenic, antimony, antimony, bismuth, lithium

Antimony have having five valence electrons but, silicon or germanium need only four valance electrons. it forms four covalent bonds. But, one electron will be left excess in Antimony Thus, each Antimony atom leaves one excess electron in the germanium crystal.

As an extremely small amount of Antimony impurity has a large number of atoms, therefore, it provides millions of electrons in the semiconductor.
diode2Energy band diagram :


image4148018826127983080_4344358628830754028
Labels:

Comments

Post a Comment

Popular posts from this blog

relay

A relay is an electrically operated switch. These are remote control electrical switches that are controlled by another switch. A relay is used to isolate one electrical circuit from another. It allows a low current control circuit to make or break an electrically isolated high current circuit path. The basic relay consists of a coil and a set of contacts. The most common relay coil is a length of magnet wire wrapped around a metal core. When voltage is applied to the coil, current passes through the wire and creates a magnetic field. This magnetic field pulls the contacts together and holds them there until the current flow in the coil has stopped. The diagram below shows the parts of a simple relay. Operation: When a current flows through the coil, the resulting magnetic field attracts an armature that is mechanically linked to a moving contact. The movement either makes or breaks a connection with a fixed contact. When the current is switched off, the armature is usually returned by...
1 comment
Read more

Tellegens Theorem

Tellegen theorem states that  the summation of instantaneous powers for the n number of branches in an electrical network is zero. Suppose n number of branches in an electrical network have i 1 , i 2 , i 3 , .............i n respective instantaneous currents through them. These currents satisfy Kirchhoff's Current Law . Again, suppose these branches have instantaneous voltages across them are v 1 , v 2 , v 3 , ........... v n respectively. If these voltages across these elements satisfy Kirchhoff Voltage Law then,
1 comment
Read more

Lorentz force equation

  Lorentz Force Equation   The force experienced by current element in magnetic field is given as sum of force due to electric field and magnetic field.   Force due to electric field: A region is said to be characterized by an electric field if a particle of charge q moving with a velocity v experiences a force Fe, independent of v. The force, Fe, is given by              F e = qE ---------------------------------------- (1.1)                    E is the electric field intensity. Measured in newtons per coulomb (N/C) or volts per meter. Where volt is a newton-meter per coulomb. The line integral of E between two points A and B in an electric field region gives voltage between A and B. It is the work per unit charge done by the field in the movement of the charge from A to B. Force due to magnetic field: If a charged particle experiences a force which depends on v, then the region is said to be characterized by a magnetic field. The force, Fm, is given by                     F m =...
2 comments
Read more