An extrinsic semiconductor is one that has been doped; during manufacture of the semiconductor crystal a trace element or chemical called a doping agent has been incorporated chemically into the crystal, for the purpose of giving it different electrical properties than the pure semiconductor crystal, which is called an intrinsic semiconductor. In an extrinsic semiconductor it is these foreign dopant atoms in the crystal lattice that mainly provide the charge carriers which carry electric current through the crystal. The doping agents used are of two types, resulting in two types of extrinsic semiconductor. An electron donor dopant is an atom which, when incorporated in the crystal, releases a mobile conduction electron into the crystal lattice. An extrinsic semiconductor which has been doped with electron donor atoms is called an n-type semiconductor, because the majority of charge carriers in the crystal are negative electrons. An electron acceptor dopant is an atom which accepts an electron from the lattice, creating a vacancy where an electron should be called a hole which can move through the crystal like a positively charged particle. 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. Doping is the key to the extraordinarily wide range of electrical behavior that semiconductors can exhibit, and extrinsic semiconductors are used to make semiconductor electronic devices such as diodes, transistors, integrated circuits, semiconductor lasers, LEDs, and photovoltaic cells. Sophisticated semiconductor fabrication processes like photolithography can implant different dopant elements in different regions of the same semiconductor crystal wafer, creating semiconductor devices on the wafer's surface. For example a common type of transistor, the n-p-n bipolar transistor, consists of an extrinsic semiconductor crystal with two regions of n-type semiconductor, separated by a region of p-type semiconductor, with metal contacts attached to each part. (Wikipedia).
Mod-01 Lec-37 Semiconductors (Continued)
Condensed Matter Physics by Prof. G. Rangarajan, Department of Physics, IIT Madras. For more details on NPTEL visit http://nptel.iitm.ac.in
From playlist NPTEL: Condensed Matter Physics - CosmoLearning.com Physics Course
Semiconductors 1: intrinsic & extrinsic semiconductors (Higher Physics)
Higher Physics - first in a series of 3 videos on semiconductors. This video covers intrinsic semiconductors, band theory and doping to form n-type or p-type semiconductors. ----------------------------------------------------- Support the channel – you can buy me a coffee here... http
From playlist Higher - Electricity
Rather than just relying on intrinsic electrons in polls it is possible doped semiconductors with electronic donors and acceptors. These provide the ability to dope and material to be either n-type or p-type. We show this with examples of phosphorus and boron doping into the silicon lattic
From playlist Materials Sciences 101 - Introduction to Materials Science & Engineering 2020
Electronic devices made possible by p-n junctions
0:00 review of intrinsic semiconductors and introduction of p and n type extrinsic semiconductors along with description of band diagrams for these (donor and acceptor states within the band gap) 18:11 why do bands form? What do they really look like? 23:15 temperature dependence of carrie
From playlist Introduction to Materials Science & Engineering Fall 2019
JEE Main Physics E & M #39 Extrinsic Semiconductors
Visit http://ilectureonline.com for more math and science lectures! To donate: http://www.ilectureonline.com/donate https://www.patreon.com/user?u=3236071 For extrinsic semiconductors; when doping levels are increased A) Fermi-level of P and n-type semiconductors will not be affected. B)
From playlist THE "WHAT IS" PLAYLIST
Intrinsic semiconductors are pure, stoichiometric materials that have not been doped with additional compounds in order to modify their electrical conductivity. The band gap of these materials increases as we move from group IV materials like silicon and germanium to III-V (GaAs etc) and I
From playlist Materials Sciences 101 - Introduction to Materials Science & Engineering 2020
What are Conductors and Insulators? | Don't Memorise
There are lots of ways to categorise different materials based on their Physical or Chemical Properties. One way is to categorise them based on their CONDUCTIVITY! Based on this property, we classify materials as Conductors, Insulators and Semiconductors. In this video, we will study abou
From playlist Physics
Semiconductors - Physics inside Transistors and Diodes
Bipolar junction transistors and diodes explained with energy band levels and electron / hole densities. My Patreon page is at https://www.patreon.com/EugeneK
From playlist Physics
Semiconductors are in everything from your cell phone to rockets. But what exactly are they, and what makes them so special? Find out from Jamie, a Ph.D. student in Electrical Engineering and Computer Science at MIT. More information on semiconductors from MIT: https://www.pinterest.com/m
From playlist Science Out Loud
Mod-06 Lec-14 Electrical Conduction in Ceramics ( Contd.)
Advanced ceramics for strategic applications by Prof. H.S. Maiti,Department of Metallurgy and Material Science,IIT Kharagpur.For more details on NPTEL visit http://nptel.ac.in
From playlist IIT Kharagpur: Advanced Ceramics for Strategic Applications | CosmoLearning.org Materials Science
Temperature and dopant dependence of electrical conductivity in semiconductors
Metals become less conductive as they are heated due to atomic vibrations increasing. The thermal vibrations also increase and affect the mobility of carriers in semiconductors, but at the same time there is exponential increase in the number of carriers being promoted across the band gap.
From playlist Materials Sciences 101 - Introduction to Materials Science & Engineering 2020
0:00 review of extrinsic doping 3:45 temperature dependence of electrical conductivity in metals vs semiconductors 6:29 band gap as an "activation energy" for intrinsic carrier concentration 11:49 freeze-out, extrinsic, and intrinsic semiconductor regions 15:33 carrier mobility vs dopant c
From playlist Introduction to Materials Science and Engineering Fall 2018
Day 35 intrinsic and extrinsic semiconductors
0:00 mystery prizes for best HW9 presentation 2:00 reading quiz 6:23 Thermoelectric cooler/generator demonstration and discussion 13:10 band gap changes with interatomic separation 14:00 understanding metals vs semiconductors vs insulators using band diagrams, conduction band, valence band
From playlist Introduction to Materials Science and Engineering Fall 2017
Condensed Matter Physics by Prof. G. Rangarajan, Department of Physics, IIT Madras. For more details on NPTEL visit http://nptel.iitm.ac.in
From playlist NPTEL: Condensed Matter Physics - CosmoLearning.com Physics Course
https://www.patreon.com/edmundsj If you want to see more of these videos, or would like to say thanks for this one, the best way you can do that is by becoming a patron - see the link above :). And a huge thank you to all my existing patrons - you make these videos possible. In this video
From playlist Electronics I: Semiconductor Physics and Devices
0:00 recap of last class extrinsic semiconductors 2:30 learning objectives and reading quiz 7:06 electrical conductivity in intrinsic semiconductors 9:14 intrinsic semiconduction as a function of temperature 10:00 using carrier concentration vs temperature to estimate band gap 12:48 diagra
From playlist Introduction to Materials Science and Engineering Fall 2017