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Thermal Laser Epitaxy
Thermal laser epitaxy (TLE) is a physical vapor deposition technique that utilizes irradiation from continuous-wave lasers to heat sources locally for growing films on a substrate. This technique can be performed under ultra-high vacuum pressure or in the presence of a background atmosphere, such as ozone, to deposit oxide films. TLE operates at power densities between 104 – 106 W/cm2, which results in evaporation or sublimation of the source material, with no plasma or high-energy particle species being produced. Despite operating at comparatively low power densities, TLE is capable of depositing many materials with low vapor pressures, including refractory metals, a process that is challenging to perform with molecular beam epitaxy. Physical process TLE uses continuous-wave lasers (typically with a wavelength of around 1000 nm) located outside the vacuum chamber to heat sources of material in order to generate a flux of vapor via evaporation or sublimation. O ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Physical Vapor Deposition
Physical vapor deposition (PVD), sometimes called physical vapor transport (PVT), describes a variety of vacuum deposition methods which can be used to produce thin films and coatings on substrates including metals, ceramics, glass, and polymers. PVD is characterized by a process in which the material transitions from a condensed phase to a vapor phase and then back to a thin film condensed phase. The most common PVD processes are sputtering and evaporation Evaporation is a type of vaporization that occurs on the surface of a liquid as it changes into the gas phase. High concentration of the evaporating substance in the surrounding gas significantly slows down evaporation, such as when hu .... PVD is used in the manufacturing of items which require thin films for optical, mechanical, electrical, acoustic or chemical functions. Examples include semiconductor devices such as thin-film solar cells, microelectromechanical devices such as thin film bulk acoustic reso ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Temperature
Temperature is a physical quantity that expresses quantitatively the perceptions of hotness and coldness. Temperature is measured with a thermometer. Thermometers are calibrated in various temperature scales that historically have relied on various reference points and thermometric substances for definition. The most common scales are the Celsius scale with the unit symbol °C (formerly called ''centigrade''), the Fahrenheit scale (°F), and the Kelvin scale (K), the latter being used predominantly for scientific purposes. The kelvin is one of the seven base units in the International System of Units (SI). Absolute zero, i.e., zero kelvin or −273.15 °C, is the lowest point in the thermodynamic temperature scale. Experimentally, it can be approached very closely but not actually reached, as recognized in the third law of thermodynamics. It would be impossible to extract energy as heat from a body at that temperature. Temperature is important in all fields of na ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Semiconductor Device Fabrication
Semiconductor device fabrication is the process used to manufacture semiconductor devices, typically integrated circuit (IC) chips such as modern computer processors, microcontrollers, and memory chips such as NAND flash and DRAM that are present in everyday electrical and electronics, electronic devices. It is a multiple-step sequence of Photolithography, photolithographic and chemical processing steps (such as surface passivation, thermal oxidation, planar process, planar diffusion and p–n junction isolation, junction isolation) during which electronic circuits are gradually created on a wafer (electronics), wafer made of pure semiconducting material. Silicon is almost always used, but various compound semiconductors are used for specialized applications. The entire manufacturing process takes time, from start to packaged chips ready for shipment, at least six to eight weeks (tape-out only, not including the circuit design) and is performed in highly specialized semiconduct ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thin Film Deposition
A thin film is a layer of material ranging from fractions of a nanometer (monolayer) to several micrometers in thickness. The controlled synthesis of materials as thin films (a process referred to as deposition) is a fundamental step in many applications. A familiar example is the household mirror, which typically has a thin metal coating on the back of a sheet of glass to form a reflective interface. The process of silvering was once commonly used to produce mirrors, while more recently the metal layer is deposited using techniques such as sputtering. Advances in thin film deposition techniques during the 20th century have enabled a wide range of technological breakthroughs in areas such as magnetic recording media, electronic semiconductor devices, integrated passive devices, LEDs, optical coatings (such as antireflective coatings), hard coatings on cutting tools, and for both energy generation (e.g. thin-film solar cells) and storage ( thin-film batteries). It is also bein ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tungsten
Tungsten, or wolfram, is a chemical element with the symbol W and atomic number 74. Tungsten is a rare metal found naturally on Earth almost exclusively as compounds with other elements. It was identified as a new element in 1781 and first isolated as a metal in 1783. Its important ores include scheelite and wolframite, the latter lending the element its alternate name. The free element is remarkable for its robustness, especially the fact that it has the highest melting point of all known elements barring carbon (which sublimes at normal pressure), melting at . It also has the highest boiling point, at . Its density is , comparable with that of uranium and gold, and much higher (about 1.7 times) than that of lead. Polycrystalline tungsten is an intrinsically brittle and hard material (under standard conditions, when uncombined), making it difficult to work. However, pure single-crystalline tungsten is more ductile and can be cut with a hard-steel hacksaw. Tungsten o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbon
Carbon () is a chemical element with the symbol C and atomic number 6. It is nonmetallic and tetravalent—its atom making four electrons available to form covalent chemical bonds. It belongs to group 14 of the periodic table. Carbon makes up only about 0.025 percent of Earth's crust. Three isotopes occur naturally, C and C being stable, while C is a radionuclide, decaying with a half-life of about 5,730 years. Carbon is one of the few elements known since antiquity. Carbon is the 15th most abundant element in the Earth's crust, and the fourth most abundant element in the universe by mass after hydrogen, helium, and oxygen. Carbon's abundance, its unique diversity of organic compounds, and its unusual ability to form polymers at the temperatures commonly encountered on Earth, enables this element to serve as a common element of Carbon-based life, all known life. It is the second most abundant element in the human body by mass (about 18.5%) after oxygen. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Max Planck Institute For Solid State Research
The Max Planck Institute for Solid State Research (German: ''Max-Planck-Institut für Festkörperforschung'') was founded in 1969 and is one of the 82 Max Planck Institutes of the Max Planck Society. It is located on a campus in Stuttgart, together with the Max Planck Institute for Intelligent Systems. Research focus Research at the Max Planck Institute for Solid State Research is focused on the physics and chemistry of condensed matter, including especially complex materials and nanoscale science. In both of these fields, electronic and ionic transport phenomena are of particular interest. Organization The institute currently has eight departments. Electronic Structure Theory Led by Ali Alavi, the Department of Electronic Structure Theory is concerned with the development of ab initio methods for treating correlated electronic systems, using Quantum Monte Carlo, quantum chemical and many-body methodologies. Ab initio methods (including density functional theory) will be a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pulsed Laser Deposition
Pulsed laser deposition (PLD) is a physical vapor deposition (PVD) technique where a high-power pulsed laser beam is focused inside a vacuum chamber to strike a target of the material that is to be deposited. This material is vaporized from the target (in a plasma plume) which deposits it as a thin film on a substrate (such as a silicon wafer facing the target). This process can occur in ultra high vacuum or in the presence of a background gas, such as oxygen which is commonly used when depositing oxides to fully oxygenate the deposited films. While the basic setup is simple relative to many other deposition techniques, the physical phenomena of laser-target interaction and film growth are quite complex (see Process below). When the laser pulse is absorbed by the target, energy is first converted to electronic excitation and then into thermal, chemical and mechanical energy resulting in evaporation, ablation, plasma formation and even exfoliation.Pulsed Laser Deposition of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Theodore H
Theodore may refer to: Places * Theodore, Alabama, United States * Theodore, Australian Capital Territory * Theodore, Queensland, a town in the Shire of Banana, Australia * Theodore, Saskatchewan, Canada * Theodore Reservoir, a lake in Saskatchewan People * Theodore (given name), includes the etymology of the given name and a list of people * Theodore (surname), a list of people Fictional characters * Theodore "T-Bag" Bagwell, on the television series ''Prison Break'' * Theodore Huxtable, on the television series ''The Cosby Show'' Other uses * Theodore (horse), a British Thoroughbred racehorse * Theodore Racing, a Formula One racing team See also * Principality of Theodoro The Principality of Theodoro ( el, Αὐθεντία πόλεως Θεοδωροῦς καὶ παραθαλασσίας), also known as Gothia ( el, Γοτθία) or the Principality of Theodoro-Mangup, was a Greek principality in the southern pa ..., a principality in the south-west Crimea from the 13th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
High-temperature Superconductivity
High-temperature superconductors (abbreviated high-c or HTS) are defined as materials with critical temperature (the temperature below which the material behaves as a superconductor) above , the boiling point of liquid nitrogen. They are only "high-temperature" relative to previously known superconductors, which function at even colder temperatures, close to absolute zero. The "high temperatures" are still far below ambient (room temperature), and therefore require cooling. The first break through of high-temperature superconductor was discovered in 1986 by IBM researchers Georg Bednorz and K. Alex Müller. Although the critical temperature is around , this new type of superconductor was readily modified by Ching-Wu Chu to make the first high-temperature superconductor with critical temperature . Bednorz and Müller were awarded the Nobel Prize in Physics in 1987 "for their important break-through in the discovery of superconductivity in ceramic materials". Most high-c mate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
_250_nm_by_250_nm_image_of_one-atom-thick_silver_islands_grown_on_palladium_(111)_surface.png "Click for more on -> Thin Film Deposition")
