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Nanocrystalline Silicon
Nanocrystalline silicon (nc-Si), sometimes also known as microcrystalline silicon (μc-Si), is a form of porous silicon. It is an allotropic form of silicon with paracrystalline structure—is similar to amorphous silicon (a-Si), in that it has an amorphous phase. Where they differ, however, is that nc-Si has small grains of crystalline silicon within the amorphous phase. This is in contrast to polycrystalline silicon (poly-Si) which consists solely of crystalline silicon grains, separated by grain boundaries. The difference comes solely from the grain size of the crystalline grains. Most materials with grains in the micrometre range are actually fine-grained polysilicon, so nanocrystalline silicon is a better term. The term Nanocrystalline silicon refers to a range of materials around the transition region from amorphous to microcrystalline phase in the silicon thin film. The crystalline volume fraction (as measured from Raman spectroscopy) is another criterion to describe the ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nano Si 640x480
Nano, Nano-, NANO or NaNo may refer to: People * Nano (singer) (born 1988), Japanese-American J-pop singer * Nano Omar (born 1986), Swedish singer * Nano Riantiarno (born 1949), Indonesian director * Agnese Nano (born 1965), Italian actress * Fatos Nano (born 1952), former Prime Minister of Albania * Lourdes Flores Nano (born 1959), Peruvian politician * Nano Macedo (born 1982), Spanish football winger, full name Fernando Macedo da Silva Rodilla * Nano Mesa (born 1995), Spanish football forward, full name Alexander Mesa Travieso * Nano Rivas (born 1980), Spanish football defender, full name Victoriano Rivas Álvaro * Nano (Egyptian footballer) (born 1985), Egyptian football defender/midfielder, full name Mohamed Mahmoud * Nano (footballer, born 1982), Spanish football winger, full name Fernando Macedo da Silva Rodilla * Nano (footballer, born 1984), Spanish football defender, full name Mariano González Maroto Science and technology * GNU nano, a text editor for Unix-like sy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Annealing (metallurgy)
In metallurgy and materials science, annealing is a heat treatment that alters the physical and sometimes chemical properties of a material to increase its ductility and reduce its hardness, making it more workable. It involves heating a material above its recrystallization temperature, maintaining a suitable temperature for an appropriate amount of time and then cooling. In annealing, atoms migrate in the crystal lattice and the number of dislocations decreases, leading to a change in ductility and hardness. As the material cools it recrystallizes. For many alloys, including carbon steel, the crystal grain size and phase composition, which ultimately determine the material properties, are dependent on the heating rate and cooling rate. Hot working or cold working after the annealing process alters the metal structure, so further heat treatments may be used to achieve the properties required. With knowledge of the composition and phase diagram, heat treatment can be used t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allotropes Of Silicon
Allotropes of silicon are structurally varied forms of silicon. Amorphous silicon Amorphous silicon takes the form of a brown powder. Crystalline silicon Crystalline silicon has a metallic luster and a grayish color. Single crystals can be grown with the Czochralski process. Crystalline silicon can be doped with elements such as boron, gallium, germanium, phosphorus or arsenic. Doped silicon is used in solid-state electronic devices, such as solar cells, rectifiers and computer chips. Silicon crystallizes in the same pattern as germanium and diamond, viewable as two interpenetrating face-centered cubic primitive lattices. The cube measures 0.543 nm on a side. Silicene Silicene is a two-dimensional system with a hexagonal honeycomb structure similar to that of graphene. Silicene has different characteristics than graphene. It has a periodically buckled topology; interlayer coupling is much stronger; and its oxidized form, 2D silica, has a different chemical structure ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quantum Dot
Quantum dots (QDs) or semiconductor nanocrystals are semiconductor particles a few nanometres in size with optical and electronic properties that differ from those of larger particles via quantum mechanical effects. They are a central topic in nanotechnology and materials science. When a quantum dot is illuminated by UV light, an electron in the quantum dot can be excited to a state of higher energy. In the case of a semiconducting quantum dot, this process corresponds to the transition of an electron from the valence band to the conduction band. The excited electron can drop back into the valence band releasing its energy as light. This light emission ( photoluminescence) is illustrated in the figure on the right. The color of that light depends on the energy difference between the discrete energy levels of the quantum dot in the conduction band and the valence band. In other words, a quantum dot can be defined as a structure on a semiconductor which is capable of confi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protocrystalline
A protocrystalline phase is a distinct phase occurring during crystal growth, which evolves into a microcrystalline form. The term is typically associated with silicon films in optical applications such as solar cells. Applications Silicon solar cells Amorphous silicon (a-Si) is a popular solar cell material owing to its low cost and ease of production. Owing to its disordered structure ( Urbach tail), its absorption extends to the energies below the band gap, resulting in a wide-range spectral response; however, it has a relatively low solar cell efficiency. Protocrystalline Si (pc-Si:H) also has a relatively low absorption near the band gap, owing to its more ordered crystalline structure. Thus, protocrystalline and amorphous silicon can be combined in a tandem solar cell, where the top thin layer of a-Si:H absorbs short-wavelength light whereas the underlying protocrystalline silicon layer absorbs the longer wavelengths See also *Amorphous silicon *Crystallite * Multijunc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Printed Electronics
Printed electronics is a set of printing methods used to create electrical devices on various substrates. Printing typically uses common printing equipment suitable for defining patterns on material, such as screen printing, flexography, gravure, offset lithography, and inkjet. By electronic-industry standards, these are low-cost processes. Electrically functional electronic or optical inks are deposited on the substrate, creating active or passive devices, such as thin film transistors, capacitors, coils, and resistors. Some researchers expect printed electronics to facilitate widespread, very low-cost, low-performance electronics for applications such as flexible displays, smart labels, decorative and animated posters, and active clothing that do not require high performance. Coatanéa, E., Kantola, V., Kulovesi, J., Lahti, L., Lin, R., & Zavodchikova, M. (2009). Printed Electronics, Now and Future. In Neuvo, Y., & Ylönen, S. (eds.), Bit Bang – Rays to the Future. Helsinki Un ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nanoparticle
A nanoparticle or ultrafine particle is a particle of matter 1 to 100 nanometres (nm) in diameter. The term is sometimes used for larger particles, up to 500 nm, or fibers and tubes that are less than 100 nm in only two directions. At the lowest range, metal particles smaller than 1 nm are usually called atom clusters instead. Nanoparticles are distinguished from microparticles (1-1000 μm), "fine particles" (sized between 100 and 2500 nm), and "coarse particles" (ranging from 2500 to 10,000 nm), because their smaller size drives very different physical or chemical properties, like colloidal properties and ultrafast optical effects or electric properties. Being more subject to the Brownian motion, they usually do not sediment, like colloid, colloidal particles that conversely are usually understood to range from 1 to 1000 nm. Being much smaller than the wavelengths of visible light (400-700 nm), nanoparticles cannot be seen with ordinary ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conductive Ink
Conductive ink is an ink that results in a printed object which conducts electricity. It is typically created by infusing graphite or other conductive materials into ink. There has been a growing interest in replacing metallic materials with nanomaterials due to the emergence of nanotechnology. Among other nanomaterials, graphene, and carbon nanotube-based conductive ink are gaining immense popularity due to their high electrical conductivity and high surface area. Recently, more attention has been paid on using eco-friendly conductive ink using water as a solvent as compared to organic solvents since they are harmful to the environment. However, the high surface tension of water prevents its applicability. Various natural and synthetic surfactants are now used to reduce the surface tension of water and ensure uniform nanomaterials dispersibility for smooth printing and wide application. Although graphene oxide inks are eco-friendly and can be produced in bulk quantities, they ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amorphous Silicon
Amorphous silicon (a-Si) is the non-crystalline form of silicon used for solar cells and thin-film transistors in LCDs. Used as semiconductor material for a-Si solar cells, or thin-film silicon solar cells, it is deposited in thin films onto a variety of flexible substrates, such as glass, metal and plastic. Amorphous silicon cells generally feature low efficiency. As a second-generation thin-film solar cell technology, amorphous silicon was once expected to become a major contributor in the fast-growing worldwide photovoltaic market, but has since lost its significance due to strong competition from conventional crystalline silicon cells and other thin-film technologies such as CdTe and CIGS. Amorphous silicon is a preferred material for the thin film transistor (TFT) elements of liquid crystal displays (LCDs) and for x-ray imagers. Amorphous silicon differs from other allotropic variations, such as monocrystalline silicon—a single crystal, and polycrystalline silico ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thin-film Silicon
Amorphous silicon (a-Si) is the non-crystalline form of silicon used for solar cells and thin-film transistors in liquid-crystal display, LCDs. Used as semiconductor material for a-Si solar cells, or thin-film silicon solar cells, it is deposited in thin films onto a variety of flexible substrates, such as glass, metal and plastic. Amorphous silicon cells generally feature low efficiency. As a second-generation thin-film solar cell technology, amorphous silicon was once expected to become a major contributor in the Growth of photovoltaics, fast-growing worldwide photovoltaic market, but has since lost its significance due to strong competition from conventional crystalline silicon cells and other thin-film technologies such as Cadmium telluride photovoltaics, CdTe and CIGS solar cell, CIGS. Amorphous silicon is a preferred material for the Thin-film transistor, thin film transistor (TFT) elements of Liquid-crystal display, liquid crystal displays (LCDs) and for x-ray imagers. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Semiconductor
A semiconductor is a material with electrical conductivity between that of a conductor and an insulator. Its conductivity can be modified by adding impurities (" doping") to its crystal structure. When two regions with different doping levels are present in the same crystal, they form a semiconductor junction. The behavior of charge carriers, which include electrons, ions, and electron holes, at these junctions is the basis of diodes, transistors, and most modern electronics. Some examples of semiconductors are silicon, germanium, gallium arsenide, and elements near the so-called " metalloid staircase" on the periodic table. After silicon, gallium arsenide is the second-most common semiconductor and is used in laser diodes, solar cells, microwave-frequency integrated circuits, and others. Silicon is a critical element for fabricating most electronic circuits. Semiconductor devices can display a range of different useful properties, such as passing current more easil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tandem Cell
Multi-junction (MJ) solar cells are solar cells with multiple p–n junctions made of different semiconductor materials. Each material's p–n junction will produce electric current in response to different wavelengths of light. The use of multiple semiconducting materials allows the absorbance of a broader range of wavelengths, improving the cell's sunlight to electrical energy conversion efficiency. Traditional single-junction cells have a maximum theoretical efficiency of 33.16%. Theoretically, an infinite number of junctions would have a limiting efficiency of 86.8% under highly concentrated sunlight. As of 2024 the best lab examples of traditional crystalline silicon (c-Si) solar cells had efficiencies up to 27.1%, while lab examples of multi-junction cells have demonstrated performance over 46% under concentrated sunlight. Commercial examples of tandem cells are widely available at 30% under one-sun illumination, and improve to around 40% under concentrated sunlight. How ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
