Article ID Journal Published Year Pages File Type
1596147 Solid State Communications 2008 5 Pages PDF
Abstract

Photoluminescence peak energy at 15 K in amorphous hydrogenated silicon (a-Si:H), prepared at substrate temperatures (Ts=Ts=) 180–250 ∘C, increases with excitation energy in the excitation energy range lower than 1.52 eV in the Urbach tail region whilst for higher excitation energy range the peak energy is constant. The excitation energy at which the peak energy becomes constant is named the hopping-gap. The a-Si:H prepared at TsTs lower than 180 ∘C has higher hopping-gaps. Furthermore, it is shown that the rate of increase of the peak energy to the excitation energy agrees with that in photoluminescence of porous Si. The photoluminescence in a-Si:H is concluded to be due to the radiative recombination of electron–hole pairs quantum-confined in hydrogen-free Si nanostructures with a radius of 3–5 nm.

Related Topics
Physical Sciences and Engineering Materials Science Materials Science (General)
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