Absorption and photoluminescence spectra of the hydrogenated amorphous silicon with embedded silicon nanoparticles

0471064 - FZÚ 2017 RIV CZ eng A - Abstract
Remeš, Zdeněk - Stuchlík, Jiří - Purkrt, Adam - Kupčík, Jaroslav
Absorption and photoluminescence spectra of the hydrogenated amorphous silicon with embedded silicon nanoparticles.
Development of Materials Science in Research and Education. Book of Abstracts of the 26th Joint Seminar. Praha: Institute of Physics of the Czech Academy of Sciences, v. v. i., 2016 - (Kožíšek, Z.; Král, R.; Zemenová, P.). s. 39. ISBN 978-80-905962-4-5.
[Joint Seminar Development of Materials Science in Research and Education /26./. 29.08.2016-02.09.2016, Pavlov]
R&D Projects: GA ČR GC16-10429J
Institutional support: RVO:68378271 ; RVO:61388980
Keywords : amorphous silicon * silicon nanoparticles * photoluminescence
Subject RIV: BM - Solid Matter Physics ; Magnetism

Silicon nanoparticles (NPs) embedded in the hydrogenated amorphous silicon (a-Si:H) open the opportunity for a new nanocomposite semiconducting material suitable for low cost, large area energy conversion applications. The intrinsic hydrogenated silicone layers with embedded silicon NPs were grown in-situ on glass substrates at 250 ◦C by the radio frequency plasma enhanced chemical vapor deposition (CVD) from silane highly diluted in hydrogen. The changes in the sub-band gap optical absorption were measured by the photothemal deflection spectroscopy (PDS). The transition from amorphous to crystalline phase for samples deposited at 5-6 % silane concentration corresponds to the crystalline volume fraction about 50 % as detected by Raman spectroscopy. The room temperature photo-luminescence increases significantly with increased crystallinity volume fraction and diminishes abruptly when crystallinity volume fraction exceeds above 80 %. Thus, we have found that the photoluminescence intensity strongly correlates with the presence of isolated silicon nanoparticles in the mixed amorphous and crystalline phase as confirmed by the high resolution transmission electron microscopy (HRTEM). The strongest photoluminescence was found in the sample with mixed phase of amorphous matrix and isolated silicon nanoparticles and the crystalline volume fraction about 50 %.
Permanent Link: http://hdl.handle.net/11104/0268526