Some substances like Germanium, Silicon, Carbon, etc. are neither good conductors like copper nor insulators like glass. The resistivity of these materials lies in between conductors and insulators. Such substances are known as semiconductors.
Read MoreWhat is Conductor, insulator & semiconductor?
The pure crystal of semiconductor (Si or Ge) is known as intrinsic semiconductor at room temperature. The Silicon atom has 14 electrons revolving around its nucleus. In first orbit it contains 2 electrons, in second orbit 8 electrons i.e. 4 electrons in last orbit, known as valence electrons.
Read MoreWhat is Intrinsic Semiconductor?
The devices like diodes, transistors, ICs used in electronic circuits are manufactured with the help of extrinsic semiconductor. When a trivalent or pentavalent element is mixed with pure Silicon crystal (i.e. intrinsic semiconductor), the new material is formed known as extrinsic semiconductor.
Read MoreWhat is Extrinsic Semiconductor?
At temperatures above absolute zero, some electrons are excited out over the band gap into the conduction band. When the electron in pure silicon crosses the gap, it creates a vacancy, known as a hole, in the regular silicon lattice. A hole means actually nothing. But since it can accept an electron to get occupied into it, it is assumed to have a positive charge.
Read MoreCrystal Structure & Behavior of semiconductor
The PN junction diode conducts only in one direction. So it is known as unidirectional current device. Before going to understand the energy level diagrams, please read construction and biasing of diode.
Read MoreComparative Analysis of Energy Level Diagrams
A PN junction diode is the first semiconductor device in semiconductor family. It is also known as unidirectional current device, because it allows current only in one direction through it.
Read MoreConstruction of PN junction diode
Diodes are very cheap in cost, so it is a general thing that every electronic hobbyist has large number of diodes in his/her stock. When you pick up a diode from your stock, sometimes the cathode marking band on the body of diode, may be wiped out, so its difficult to find our the anode and cathode just by looking at it.
Read MoreHow to find out the anode & cathode of a diode using a multimeter?
When the external voltage applied to the PN junction is in such a direction that it cancels the potential barrier, thus permitting current flow, is called as forward biasing.
Read MoreWhat is Forward & Reverse Biasing of PN Junction?
A rectifier circuit converts AC into DC. It uses diodes for this conversion, because the diode passes current only in one direction. There are three types of rectifier circuits, HWR, FWR and BR.
Read MoreRectifier Circuits: HWR, FWR & BR
