A protocrystalline phase is a distinct phase occurring during
crystal growth
A crystal is a solid material whose constituent atoms, molecules, or ions are arranged in an orderly repeating pattern extending in all three spatial dimensions. Crystal growth is a major stage of a crystallization process, and consists of ...
which evolves into a
microcrystalline
A microcrystalline material is a crystallized substance or rock that contains small crystals visible only through microscopic examination. There is little agreement on the range of crystal sizes that should be regarded as microcrystalline, but th ...
form. The term is typically associated with
silicon
Silicon is a chemical element with the symbol Si and atomic number 14. It is a hard, brittle crystalline solid with a blue-grey metallic luster, and is a tetravalent metalloid and semiconductor. It is a member of group 14 in the periodic ...
films in
optical
Optics is the branch of physics that studies the behaviour and properties of light, including its interactions with matter and the construction of instruments that use or detect it. Optics usually describes the behaviour of visible, ultrav ...
applications such as
solar cell
A solar cell, or photovoltaic cell, is an electronic device that converts the energy of light directly into electricity by the photovoltaic effect, which is a physical and chemical phenomenon.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 longer wavelengths are absorbed by the underlying protocrystalline silicon layer.
See also
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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 ...
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Crystallite
A crystallite is a small or even microscopic crystal which forms, for example, during the cooling of many materials. Crystallites are also referred to as grains.
Bacillite is a type of crystallite. It is rodlike with parallel longulites.
Stru ...
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Multijunction 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 ...
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Polycarbonate
Polycarbonates (PC) are a group of thermoplastic polymers containing carbonate groups in their chemical structures. Polycarbonates used in engineering are strong, tough materials, and some grades are optically transparent. They are easily work ...