Protocrystalline

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Crystallization
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Fundamentals
Crystal  · Crystal structure  · Nucleation
Concepts
Crystallization  · Crystal growth
Recrystallization  · Seed crystal
Protocrystalline  · Single crystal
Methods and technology
Boules
Bridgman–Stockbarger method
Van Arkel–de Boer process
Czochralski method
Epitaxy  · Flux method
Fractional crystallization
Fractional freezing
Hydrothermal synthesis
Kyropoulos method
Laser-heated pedestal growth
Micro-pulling-down
Shaping processes in crystal growth
Skull crucible
Verneuil method
Zone melting

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. [1]

Contents

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 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 longer wavelengths are absorbed by the underlying protocrystalline silicon layer. [2]

See also

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References

  1. Ishikawa, Yasuaki; Schubert, Markus B. (2006-09-07). "Flexible Protocrystalline Silicon Solar Cells with Amorphous Buffer Layer". Japanese Journal of Applied Physics. 45 (9A): 6812–6822. doi:10.1143/jjap.45.6812. ISSN   0021-4922.
  2. Ahn, Jun Yong; Jun, Kyung Hoon; Lim, Koeng Su; Konagai, Makoto (2003-03-10). "Stable protocrystalline silicon and unstable microcrystalline silicon at the onset of a microcrystalline regime". Applied Physics Letters. 82 (11): 1718–1720. Bibcode:2003ApPhL..82.1718A. doi:10.1063/1.1561161. ISSN   0003-6951.