Semiconductor Physics

There are some materials, which have neither good conductivity nor bad conductivity of electricity. They have a moderate range of electrical conductivity. The examples of such materials are germanium, silicon, carbon etc. As the conductivity of those materials lies between good conductors and insulators, and these materials are called semiconductors. The atoms of semiconductor elements … Read more

Intrinsic Semiconductor

Semiconductor is a material whose conductivity lies in-between that of the conductors and the insulators. Semiconductors which are chemically pure, meaning free of impurities, are called Intrinsic Semiconductors or Undoped Semiconductor or i-type Semiconductor. The most common intrinsic semiconductors are Silicon (Si) and Germanium (Ge), which belong to Group IV of the periodic table. The … Read more

Forward and Reverse Bias of P N Junction

Forward Biased P-N Junction When we connect p-type region of a junction with the positive terminal of a voltage source and n-type region with the negative terminal of the voltage source, then the junction is said to be forward biased. At this condition, due to the attraction of positive terminal of source, electrons which participated … Read more

N Type Semiconductor

Before understanding what is n-type semiconductor we should focus on some basic theories of atomic science. We all know that each atom of any substance requires eight electrons at its outermost orbit. But it is also true that all atoms do not have eight electrons at their outermost orbit. But all the atoms have an … Read more

Conductivity of Semiconductor

It is well known to us that the conductivity of a material depends on the concentration of free electrons in it. Good conductors consist large concentration of free electrons whereas insulators consist small concentration of free electrons. The concentration level of the free electron in semiconductors is in between the values of density of free … Read more

Donor and Acceptor Impurities in Semiconductor

When we add a small quantity of impurity in a semiconductor than the impurity contributes either free electrons or holes to the semiconductor. As a result, the conducting property of semiconductor changes. The process of changing the conductive property of semiconductor by adding impurities is known as doping. Suppose, we add any pentavalent impurity in … Read more

Current Density in Metal and Semiconductor

The concept of current density is very simple but it is much use full in the field of electrical engineering. Current Density in Metal Suppose, we have taken one conductor of cross-section 2.5 square mm. Now due to applied electric potential, the conductor carries a current of 3 A. Now the electric current carried by … Read more

Hall Effect Applications of Hall Effect

Whenever we place a current carrying conductor in a magnetic field, there is a deflection of the charge carriers due influence of magnetic field in the conductor body. We call this typical phenomenon as Hall effect. Edwin Hall in 1879 had first observed the phenomenon, and hence we call this as Hall effect. Mainly Lorentz … Read more

Extrinsic Semiconductors

Semiconductor materials can be classified into two types viz., Intrinsic Semiconductors and Extrinsic Semiconductors. Semiconductors in their pure form are referred to as intrinsic semiconductors. On the other hand, the semiconductors with intentionally added impurities are called extrinsic semiconductors. This process of adding impurities in minute quantities into the pure semiconductor material under controlled conditions … Read more

Gallium Arsenide Semiconductor

Semiconductors have conductivity between that of a conductor and insulator. There are two types of semiconductor- Single Crystal Compound. Silicon, Germanium are single crystal. Gallium Arsenide (GaAs), Cadmium Sulfide (CdS), Gallium Nitride (GaN) and Gallium Arsenide Phosphide (GaAsP) are compound semiconductors. Most popularly used semiconductors are Silicon (Si), Germanium (Ge) and Gallium Arsenide (GaAs). In … Read more