The majority carriers in a p-type semiconductor are holes. In an n-type semiconductor, pentavalent impurity from the V group is added to the pure semiconductor. Examples of pentavalent impurities are Arsenic, Antimony, Bismuth etc. The pentavalent impurities provide extra electrons and are termed as donor atoms.
What is semiconductor in Ncert?
Semiconductors are the materials which have a conductivity between conductors (generally metals) and non-conductors or insulators (such as ceramics). Semiconductors can be compounds such as gallium arsenide or pure elements, such as germanium or silicon.
What is a semiconductor in chemistry?
Semiconductors. Semiconductors are materials which have a conductivity between conductors (generally metals) and nonconductors or insulators (such as most ceramics). Semiconductors can be pure elements, such as silicon or germanium, or compounds such as gallium arsenide or cadmium selenide.
Is communication system in Ncert?
Chapter 15 of NCERT Class 12 Physics is based on Communication Systems. The chapter explores the basic elements of a Communication System that help in communicating information from the source to the receiver.
What are the 2 types of semiconductors?
Semiconductors are divided into two categories: Intrinsic Semiconductor. Extrinsic Semiconductor.
Why is PN junction used?
P-N junction diode can be used as a photodiode as the diode is sensitive to the light when the configuration of the diode is reverse-biased. It can be used as a solar cell. When the diode is forward-biased, it can be used in LED lighting applications.
What is pn junction diode?
A p-n junction diode is a basic semiconductor device that controls the flow of electric current in a circuit. It has a positive (p) side and a negative (n) side created by adding impurities to each side of a silicon semiconductor. The symbol for a p-n junction diode is a triangle pointing to a line.
What is energy band?
Inside a solid crystal, each electron has a different energy level because of slightly different patterns of the surrounding charges. These electron energy levels form a continuous energy variation called as the Energy Bands.
Is communication system easy for JEE mains?
Semi conductors and communication can be treated as moderately difficult. You need to keep in kind certain things and keep your concepts clear. Also along with understanding the topic you need to mug up few things. It is an important chapter for jee mains and students must try to study it nicely.
Are transistors in JEE mains?
From this chapter very basic questions are asked in JEE MAIN(some tricky are included in JEE ADVANCED). Topics like diode and its biasing,logical gate,transistor are most common.
Is communication system in JEE mains?
Communication System Syllabus Analysis One question from unit 20, i.e., Communication System, is expected to come in the JEE Main 2021 with a weightage of 3.33%.
What is the unit of energy gap?
The energy required for electrons and holes to transition from the valence band to the conduction band is called a band gap. Si (Silicon) has a band gap of 1.12 eV (electron volt).
What are p-type materials?
What is a p-type Semiconductor? A p-type semiconductor is an intrinsic semiconductor doped with boron (B) or indium (In). Silicon of Group IV has four valence electrons and boron of Group III has three valence electrons.
Why silicon is used In semiconductor?
Silicon, a very common element, is used as the raw material of semiconductors because of its stable structure. Purification of Silicon consumes large amounts of power.
What is p-type diode?
Electronic symbol. A p–n diode is a type of semiconductor diode based upon the p–n junction. The diode conducts current in only one direction, and it is made by joining a p-type semiconducting layer to an n-type semiconducting layer.
What is Fermi level in semiconductor?
What is Fermi Level? The highest energy level that an electron can occupy at the absolute zero temperature is known as the Fermi Level. The Fermi level lies between the valence band and conduction band because at absolute zero temperature the electrons are all in the lowest energy state.
Why is it called p-type semiconductor?
An extrinsic semiconductor which has been doped with electron acceptor atoms is called a p-type semiconductor, because the majority of charge carriers in the crystal are positive holes.
What is a rectifier used for?
A rectifier is a device that converts an oscillating two-directional alternating current (AC) into a single-directional direct current (DC). Rectifiers can take a wide variety of physical forms, from vacuum tube diodes and crystal radio receivers to modern silicon-based designs.
What is P in pn junction?
The “p” (positive) side contains an excess of holes, while the “n” (negative) side contains an excess of electrons in the outer shells of the electrically neutral atoms there. This allows electrical current to pass through the junction only in one direction.
What is the formula of pn junction diode?
In a p-n junction diode, the current I can be expressed as I=I0(exp(eVKBT)−1), where I0 is called the reverse saturation current, V is the voltage across the diode and is positive for forward bias and negative for reverse bias, and I is the current through the diode, KB is the Boltzmann constant (8.6×10−5eV/K) and T is …
What is forward bias?
What is Forward Bias? Forward bias or biasing is where the external voltage is delivered across the P-N junction diode. In a forward bias setup, the P-side of the diode is attached to the positive terminal and N-side is fixed to the negative side of the battery.
What is reverse and forward bias?
Forward biasing means putting a voltage across a diode that allows current to flow easily, while reverse biasing means putting a voltage across a diode in the opposite direction. The voltage with reverse biasing doesn’t cause any appreciable current to flow. This is useful for changing AC current to DC current.
What is breakdown voltage?
Breakdown voltage is the threshold voltage at which the initiation of breakdown occurs. However, before current can flow, the open gap voltage increases until it has created an ionization path through the dielectric. Once the current starts to flow, voltage drops and stabilizes at the working gap level.
What is forbidden gap?
The gap between the valence band and the conduction band is referred to as the forbidden gap. As the name suggests, the forbidden gap doesn’t have any energy and no electrons stay in this band. If the forbidden energy gap is greater, then the valence band electrons are tightly bound or firmly attached to the nucleus.
What is energy level diagram?
An energy level diagram is a graphical representation of the energies of the various orbitals of an atom or molecule. In most cases, the energy level diagram will be represented as a series of horizontal lines, with each line representing an orbital.