The metal–oxide–semiconductor field-effect transistor known as the metal–oxide–silicon transistor, is a type of insulated-gate field-effect transistor, fabricated by the controlled oxidation of a semiconductor silicon. The voltage of the covered gate determines the electrical conductivity of the device; the MOSFET was invented by Egyptian engineer Mohamed M. Atalla and Korean engineer Dawon Kahng at Bell Labs in November 1959, it is the basic building block of modern electronics, the most manufactured device in history, with an estimated total of 13 sextillion MOSFETs manufactured between 1960 and 2018. The MOSFET is the most common semiconductor device in digital and analog circuits, the most common power device, it was the first compact transistor that could be miniaturised and mass-produced for a wide range of applications, revolutionizing the electronics industry and the world economy, having been central to the computer revolution, digital revolution, information revolution, silicon age and information age.
MOSFET scaling and miniaturization has been driving the rapid exponential growth of electronic semiconductor technology since the 1960s, enables high-density integrated circuits such as memory chips and microprocessors. The MOSFET is considered to be the most important invention in electronics, as the "workhorse" of the electronics industry and the "base technology" of the late 20th to early 21st centuries, having revolutionized modern culture, economy and daily life. A key advantage of a MOSFET is that it requires no input current to control the load current, when compared with bipolar junction transistors. In an enhancement mode MOSFET, voltage applied to the gate terminal can increase the conductivity from the "normally off" state. In a depletion mode MOSFET, voltage applied at the gate can reduce the conductivity from the "normally on" state. MOSFETs are capable of high scalability, with increasing miniaturization, can be scaled down to smaller dimensions, they have faster switching speed, much smaller size, consume less power, allow much higher density, compared to BJTs.
MOSFETs are cheaper and have simple processing steps, resulting in high manufacturing yield. MOSFETs can either be manufactured as part of MOS integrated circuit chips, or as discrete MOSFET devices. Since MOSFETs can be made with either p-type or n-type semiconductors, complementary pairs of MOSFETs can be used to make switching circuits with low power consumption, in the form of complementary MOS logic; the name "metal–oxide–semiconductor" refers to a metal gate, oxide insulation, semiconductor. However, the "metal" in the name MOSFET is sometimes a misnomer, because the gate material can be a layer of polysilicon. Along with oxide, different dielectric materials can be used with the aim of obtaining strong channels with smaller applied voltages; the MOS capacitor is part of the MOSFET structure. The basic principle of the field-effect transistor was first proposed by Austro-Hungarian physicist Julius Edgar Lilienfeld in 1926. However, his early FET concept was not a practical design; the FET concept was also theorized by Oskar Heil in the 1930s and William Shockley in the 1940s, but there was no working practical FET built at the time.
Shockley's research team attempted to build a working FET, by trying to modulate the conductivity of a semiconductor, but they were unsuccessful due to problems with the surface states, the dangling bond, the germanium and copper compound materials. In the course of trying to understand the mysterious reasons behind their failure to build a working FET, this led two members of Shockley's team, John Bardeen and Walter Brattain, to instead build a point-contact transistor, the first working transistor, in 1947, followed by Shockley's bipolar junction transistor in 1948. None of these early FET proposals involved thermally oxidized silicon, which made the MOS transistor possible. Semiconductor companies focused on junction transistors in the early years of the semiconductor industry. However, the junction transistor was a bulky device, difficult to manufacture on a mass-production basis, which limited it to a number of specialised applications. FETs were theorized as potential alternatives to junction transistors, but researchers were unable to build practical FETs due to the troublesome surface state barrier that prevented the external electric field from penetrating into the material.
By the 1950s, researchers had given up on the FET concept, instead focused on BJT technology. A breakthrough came with the work of Egyptian engineer Mohamed M. Atalla in the late 1950s, he investigated the surface properties of silicon semiconductors at Bell Labs, where he adopted a new method of semiconductor device fabrication, coating a silicon wafer with an insulating layer of silicon dioxide of controlled thickness, so that electricity could reliably penetrate to the conducting silicon below, overcoming the surface states that prevented electricity from reaching the semiconducting layer. This is known as surface passivation, a method that became critical to the semiconductor industry as it made possible the mass-production of silicon semiconductor technology, such as integrated circuit chips. For the surfac
Dena Julia Polacheck Epstein was an American music librarian and musicologist. Epstein was born in Milwaukee to Hilda Satt, she studied music at the University of Chicago and library science at the University of Illinois, graduating in 1943. She worked as a cataloguer at the latter institution while completing her degree, upon graduation was appointed the Senior Music Librarian at Newark Public Library. In 1946 she began working as a reviser for the Library of Congress music section. After spending a period as a homemaker, she returned to the University of Chicago in 1964 as the Assistant Music Librarian, in which position she served for 22 years. Beginning in 1955, Epstein began researching the historical origins of American slave music, her 1977 book on the topic, Sinful Tunes and Spirituals: black folk music to the Civil War, was awarded the Chicago Folklore Prize and the Simkins Prize of the Southern Historical Association. Among other findings, Epstein demonstrated that the banjo emerged from the African slave tradition rather than rural white culture, a revelation that "shattered myths and sparked a remarkable revival of black string band music".
Epstein received two National Endowment for the Humanities grants for her research, included in several musicology journals. She published Music Publishing in Chicago Before 1871 and I Came a Stranger: The Story of a Hull-house Girl, an edited autobiography of her mother. Epstein served as president of the Music Library Association from 1977 to 1979, was awarded the association's highest citation in 1986. MLA adjudicates a research award named after Epstein. Filmmaker Jim Carrier created The Librarian and the Banjo to document Epstein's contribution to American ethnomusicology, he noted that she "revolutionized our understanding of American music... we take for granted that African-American music is the tap root of popular American music. We owe much of that knowledge to this music librarian who set out to correct history". Epstein's papers and correspondence are held by Columbia College Chicago's Center for Black Music Research. Epstein appeared in the PBS documentary program American Experience, "Chicago, City of the Century."
Her interview regarding her mother and conditions in the Near West Side Neighborhood at the turn of the 19th century appears on Disc 3: Battle for Chicago. Dena Epstein Root & Cady Research Papers at the Newberry Library
Iman Ali, is a Pakistani actress and super model who appears in Urdu films. Ali made her film debut with a leading role in the 2007 thriller film Khuda Kay Liye, for which she won a Lux Style Award for Best Actress, she has starred as main female lead in 2016's Mah e Mir and had a supporting role in the 2011 social drama Bol. She got married with Babar Bhatti on February 21,2019. She's the daughter of veteran actor Abid Ali. In February 2019 she married Babar Bhatti, a Canada-based businessman and the grandson of Major Raja Aziz Bhatti, in Lahore. Iman is a super one of the highest-paid models of Pakistan. Ali has worked with Indian designers such as Suneet Varma, Tarun Tahiliani, Rina Dhaka, Manish Malhotra and JJ Valaya, she was the face of "Luscious Cosmetic". Ali was awarded the Lux Style Award for Best Dressed Celebrity in 2006. Ali first appeared in the serial Dil Dekay Jaien Gey followed by Arman, Woh Tees Din, Pehla Pyar and Kuch Log Roth Kar Kay Bhi. In addition, she starred alongside Shehzad Roy in the first episode of Geo New's TV Serial "Chal Parha" aired on Geo News in 2013.
In 2005, Ali appeared in Ishq Mohabbat Apna Pan in a seven-minute music video directed by Shoaib Mansoor. She made her screen debut with the leading role in the Zoheb Hassan's television series Kismat, she co-hosted the Lux Style Awards in 2005 and appeared in television productions, which ended after her breakthrough into films. In 2007, Ali made her film debut in Shoaib Mansoor's Khuda Kay Liye opposite Shaan, Fawad Khan and Naseeruddin Shah for which she received the Lux Style Awards for'Best Actress' in 2008, she appeared in a supporting role in Shoaib Mansoor's second film, Bol opposite Humaima Malik, Atif Aslam and Mahira Khan. In 2015, she appeared in lead role in Anjum Shehzad's Mah e Mir opposite Fahad Mustafa and Sanam Saeed. Iman Ali will next be starring in the upcoming film Tich Button, which began production in 2019. Kismat Arman Dil Dekay Jaien Gay Woh Tees Din Pehla Pyar Kuch Loag Rooth Kar Bhi Bewafayian Chal Parha Saiban Sheeshay ka Badshah Begum List of Pakistani models List of Pakistani actresses List of Lollywood actors Iman Ali on IMDb