Open AccessПроявление квантоворазмерных эффектов в нанокристаллах и аморфных нанокластерах германия в плeнках GeSixOy
Author(s) -
М.П. Гамбарян,
Г.К. Кривякин,
С.Г. Черкова,
M. Stoffel,
H. Rinnert,
M. Vergnat,
В.А. Володин
Publication year - 2020
Publication title -
fizika tverdogo tela
Language(s) - English
Resource type - Journals
eISSN - 1726-7498
pISSN - 0367-3294
DOI - 10.21883/ftt.2020.03.49010.600
Subject(s) - germanium , nanoclusters , annealing (glass) , photoluminescence , amorphous solid , raman spectroscopy , materials science , analytical chemistry (journal) , nanocrystal , crystallography , silicon , chemistry , nanotechnology , optoelectronics , optics , metallurgy , physics , chromatography
The non-stoichiometric germanosilicate films of two types GeOx[SiO](1-x) and GeOx [SiO2](1-x) were obtained by high-vacuum evaporation of GeO2 and either SiO or SiO2 powders and sputtering on a cold Si (001) substrate. The as-deposited and annealed (550 and 650 oC, 1 hour) samples were studied by IR spectrocopy, electron microscopy, Raman spectroscopy and photoluminescence (PL). From an analysis of Raman spectra, it was found that the as-deposited GeO[SiO2] film did not contain germanium clusters, and the as-deposited GeO[SiO] film contained amorphous germanium clusters; according to electron microscopy, it’s size was ~3 nm. According to IR spectroscopy, the films contained Si-O, Ge-O, and Si-O-Ge bonds. After annealing at 550 °C, amorphous germanium clusters were detected in both films, and after annealing at 650 °C, germanium nanocrystals were observed. A wide PL band with a maximum of 1050 nm was found in the as-deposited films at low temperatures. PL is probably due to defects, presumably oxygen vacancies and excess germanium atoms. Annealing causes a transformation of both film structure and PL spectra. In films containing germanium nanoclusters, PL is observed with a maximum of 1500–1600 nm. In this case, the PL signal from defects decreased. The temperature dependence of the intensity of the PL peaks was studied; it decreased with increasing temperature but remained at temperatures up to 200 K. The contribution to the PL from germanium nanocrystals formed during annealing is discussed.