title: Efficient visible luminescence of nanocrystalline silicon prepared from amorphous silicon films by thermal annealing and stain etching.
abstract: Films of nanocrystalline silicon (nc-Si) were prepared from hydrogenated amorphous silicon (a-Si:H) by using rapid thermal annealing. The formed nc-Si films were subjected to stain etching in hydrofluoric acid solutions in order to passivate surfaces of nc-Si. The optical reflectance spectroscopy revealed the nc-Si formation as well as the high optical quality of the formed films. The Raman scattering spectroscopy was used to estimate the mean size and volume fraction of nc-Si in the annealed films, which were about 4 to 8 nm and 44 to 90%, respectively, depending on the annealing regime. In contrast to as-deposited a-Si:H films, the nc-Si films after stain etching exhibited efficient photoluminescence in the spectral range of 600 to 950 nm at room temperature. The photoluminescence intensity and lifetimes of the stain etched nc-Si films were similar to those for conventional porous Si formed by electrochemical etching. The obtained results indicate new possibilities to prepare luminescent thin films for Si-based optoelectronics.
authors.affiliation: Department of Physics, Lomonosov Moscow State University, Leninskie Gory 1, Moscow 119991, Russia. timoshen@phys.msu.ru.
authors.forename: Victor Yur'evich
authors.initials: VY
authors.lastname: Timoshenko
authors.forename: Kirill Alexandrovich
authors.initials: KA
authors.lastname: Gonchar
authors.forename: Ivan Victorovich
authors.initials: IV
authors.lastname: Mirgorodskiy
authors.forename: Natalia Evgen'evna
authors.initials: NE
authors.lastname: Maslova
authors.forename: Valery Eduardovich
authors.initials: VE
authors.lastname: Nikulin
authors.forename: Gaukhar Kalizhanovna
authors.initials: GK
authors.lastname: Mussabek
authors.forename: Yerzhan Toktarovich
authors.initials: YT
authors.lastname: Taurbaev
authors.forename: Eldos Abugalievich
authors.initials: EA
authors.lastname: Svanbayev
authors.forename: Toktar Iskataevich
authors.initials: TI
authors.lastname: Taurbaev