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Metal-insulator-metal
Metal-insulator-metal (MIM) diode is a type of nonlinear device very similar to a semiconductor diode that is capable of very fast operation. Depending on the geometry and the material used for fabrication, the operation mechanisms are governed either by quantum tunnelling or thermal activation. In 1948, Torrey et al. stated that "It should be possible to make metal-insulator-metal rectifiers with much smaller spreading resistances than metal-semiconductor rectifiers have, consequently giving greater rectification efficiency at high frequencies". But due to fabrication difficulties, two decades passed before the first device could be successfully created. Some of the very first MIM diodes to be fabricated came from Bell Labs in the late 1960s and early 1970s Brinkman et al. demonstrated the first zero-bias MIM tunneling diode with significant responsivity. When they are using tunneling transport, the MIM diode can be very fast. As soon as 1974, this diode was reportedly used as a mi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nantenna
An optical rectenna is a rectenna (rectifying antenna) that works with visible or infrared light. A rectenna is a circuit containing an antenna and a diode, which turns electromagnetic waves into direct current electricity. While rectennas have long been used for radio waves or microwaves, an optical rectenna would operate the same way but with infrared or visible light, turning it into electricity. While traditional (radio- and microwave) rectennas are fundamentally similar to optical rectennas, it is vastly more challenging in practice to make an optical rectenna. One challenge is that light has such a high frequency—hundreds of terahertz for visible light—that only a few types of specialized diodes can switch quickly enough to rectify it. Another challenge is that antennas tend to be a similar size to a wavelength, so a very tiny optical antenna requires a challenging nanotechnology fabrication process. A third challenge is that, being very small, an optical antenna typica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thin-film Diode
Thin film diode (TFD) generally refers to any diode produced using thin-film technology. Within the flat panel display industry TFD more often refers to thin film bi-directional diodes, also known as metal-insulator-metal (MIM) TFDs or nonlinear resistors. Bi-directional MIM TFDs have very low current flow at low applied voltages, but then begin to conduct electricity above a threshold voltage, of either positive or negative polarity. Owing to this behavior these two terminal devices may be used as a switch. The exact threshold voltage at which a MIM TFD switches on and begins to conduct electricity depends on its physical dimensions, such as thickness of the insulating layer, as well as the physical properties of the materials from which it is made, such as the work function of each metal layer. Commercial applications Flat panel display manufactures have found use for MIM TFDs as switches in active matrix technology such as active matrix liquid crystal displays (AMLCD). Histori ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tunnel Junction
In electronics/spintronics, a tunnel junction is a barrier, such as a thin insulating layer or electric potential, between two electrically conducting materials. Electrons (or quasiparticles) pass through the barrier by the process of quantum tunnelling. Classically, the electron has zero probability of passing through the barrier. However, according to quantum mechanics, the electron has a non-zero wave amplitude in the barrier, and hence it has some probability of passing through the barrier. Tunnel junctions serve a variety of different purposes. Multijunction photovoltaic cell In multijunction photovoltaic cells, tunnel junctions form the connections between consecutive p-n junctions. They function as an ohmic contact, ohmic electrical contact in the middle of a semiconductor device. Magnetic tunnel junction In magnetic tunnel junctions, electrons tunnel through a thin insulating barrier from one magnetic material to another. This can serve as a basis for a magnetic detector. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tunnel Diode
A tunnel diode or Esaki diode is a type of semiconductor diode that has effectively "negative resistance" due to the quantum mechanical effect called tunneling. It was invented in August 1957 by Leo Esaki, Yuriko Kurose, and Takashi Suzuki when they were working at Tokyo Tsushin Kogyo, now known as Sony. In 1973, Esaki received the Nobel Prize in Physics, jointly with Brian Josephson, for discovering the electron tunneling effect used in these diodes. Robert Noyce independently devised the idea of a tunnel diode while working for William Shockley, but was discouraged from pursuing it. Tunnel diodes were first manufactured by Sony in 1957, followed by General Electric and other companies from about 1960, and are still made in low volume today. Tunnel diodes have a heavily doped positive-to-negative (P-N) junction that is about 10 nm (100 Å) wide. The heavy doping results in a broken band gap, where conduction band electron states on the N-side are more or le ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thin-film Diode
Thin film diode (TFD) generally refers to any diode produced using thin-film technology. Within the flat panel display industry TFD more often refers to thin film bi-directional diodes, also known as metal-insulator-metal (MIM) TFDs or nonlinear resistors. Bi-directional MIM TFDs have very low current flow at low applied voltages, but then begin to conduct electricity above a threshold voltage, of either positive or negative polarity. Owing to this behavior these two terminal devices may be used as a switch. The exact threshold voltage at which a MIM TFD switches on and begins to conduct electricity depends on its physical dimensions, such as thickness of the insulating layer, as well as the physical properties of the materials from which it is made, such as the work function of each metal layer. Commercial applications Flat panel display manufactures have found use for MIM TFDs as switches in active matrix technology such as active matrix liquid crystal displays (AMLCD). Histori ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scanning Tunneling Microscope
A scanning tunneling microscope (STM) is a type of microscope used for imaging surfaces at the atomic level. Its development in 1981 earned its inventors, Gerd Binnig and Heinrich Rohrer, then at IBM Zürich, the Nobel Prize in Physics in 1986. STM senses the surface by using an extremely sharp conducting tip that can distinguish features smaller than 0.1 nm with a 0.01 nm (10 pm) depth resolution. This means that individual atoms can routinely be imaged and manipulated. Most microscopes are built for use in ultra-high vacuum at temperatures approaching zero kelvin, but variants exist for studies in air, water and other environments, and for temperatures over 1000 °C. STM is based on the concept of quantum tunneling. When the tip is brought very near to the surface to be examined, a bias voltage applied between the two allows electrons to tunnel through the vacuum separating them. The resulting ''tunneling current'' is a function of the tip position, applied ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tunneling Diode
A tunnel diode or Esaki diode is a type of semiconductor diode that has effectively "negative resistance" due to the quantum mechanical effect called tunneling. It was invented in August 1957 by Leo Esaki, Yuriko Kurose, and Takashi Suzuki when they were working at Tokyo Tsushin Kogyo, now known as Sony. In 1973, Esaki received the Nobel Prize in Physics, jointly with Brian Josephson, for discovering the electron tunneling effect used in these diodes. Robert Noyce independently devised the idea of a tunnel diode while working for William Shockley, but was discouraged from pursuing it. Tunnel diodes were first manufactured by Sony in 1957, followed by General Electric and other companies from about 1960, and are still made in low volume today. Tunnel diodes have a heavily doped positive-to-negative (P-N) junction that is about 10 nm (100 Å) wide. The heavy doping results in a broken band gap, where conduction band electron states on the N-side are more or less ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Superconductor-insulator-superconductor
The superconducting tunnel junction (STJ) — also known as a superconductor–insulator–superconductor tunnel junction (SIS) — is an electronic device consisting of two superconductors separated by a very thin layer of insulating material. Current passes through the junction via the process of quantum tunneling. The STJ is a type of Josephson junction, though not all the properties of the STJ are described by the Josephson effect. These devices have a wide range of applications, including high-sensitivity detectors of electromagnetic radiation, magnetometers, high speed digital circuit elements, and quantum computing circuits. Quantum tunneling All currents flowing through the STJ pass through the insulating layer via the process of quantum tunneling. There are two components to the tunneling current. The first is from the tunneling of Cooper pairs. This supercurrent is described by the ac and dc Josephson relations, first predicted by Brian David Josephson in 1962. For ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Resonant Tunnelling Diode
A resonant-tunneling diode (RTD) is a diode with a resonant-tunneling structure in which electrons can tunnel through some resonant states at certain energy levels. The current–voltage characteristic often exhibits negative differential resistance regions. All types of tunneling diodes make use of quantum mechanical tunneling. Characteristic to the current–voltage relationship of a tunneling diode is the presence of one or more negative differential resistance regions, which enables many unique applications. Tunneling diodes can be very compact and are also capable of ultra-high-speed operation because the quantum tunneling effect through the very thin layers is a very fast process. One area of active research is directed toward building oscillators and switching devices that can operate at terahertz frequencies. Introduction An RTD can be fabricated using many different types of materials (such as III–V, type IV, II–VI semiconductor) and different types of resonant tu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Graphene
Graphene () is an allotrope of carbon consisting of a single layer of atoms arranged in a hexagonal lattice nanostructure. "Carbon nanostructures for electromagnetic shielding applications", Mohammed Arif Poothanari, Sabu Thomas, et al., ''Industrial Applications of Nanomaterials'', 2019. "Carbon nanostructures include various low-dimensional allotropes of carbon including carbon black (CB), carbon fiber, carbon nanotubes (CNTs), fullerene, and graphene." The name is derived from "graphite" and the suffix -ene, reflecting the fact that the allotrope of carbon contains numerous double bonds. Each atom in a graphene sheet is connecte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flat-panel Display
A flat-panel display (FPD) is an electronic display used to display visual content such as text or images. It is present in consumer, medical, transportation, and industrial equipment. Flat-panel displays are thin, lightweight, provide better linearity and are capable of higher resolution than typical consumer-grade TVs from earlier eras. They are usually less than thick. While the highest resolution for consumer-grade CRT televisions was 1080i, many flat-panel displays in the 2020s are capable of 1080p and 4K resolution. In the 2010s, portable consumer electronics such as laptops, mobile phones, and portable cameras have used flat-panel displays since they consume less power and are lightweight. As of 2016, flat-panel displays have almost completely replaced CRT displays. Most 2010s-era flat-panel displays use LCD or light-emitting diode (LED) technologies, sometimes combined. Most LCD screens are back-lit with color filters used to display colors. In many cases, flat-panel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diode
A diode is a two-terminal electronic component that conducts current primarily in one direction (asymmetric conductance); it has low (ideally zero) resistance in one direction, and high (ideally infinite) resistance in the other. A diode vacuum tube or thermionic diode is a vacuum tube with two electrodes, a heated cathode and a plate, in which electrons can flow in only one direction, from cathode to plate. A semiconductor diode, the most commonly used type today, is a crystalline piece of semiconductor material with a p–n junction connected to two electrical terminals. Semiconductor diodes were the first semiconductor electronic devices. The discovery of asymmetric electrical conduction across the contact between a crystalline mineral and a metal was made by German physicist Ferdinand Braun in 1874. Today, most diodes are made of silicon, but other semiconducting materials such as gallium arsenide and germanium are also used. Among many uses, diodes are found in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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