Nano-crystalline Si/SiO 2 multilayers were prepared by alternately changing the ultra-thin amorphous Si film deposition and the in situ plasma oxidation process followed by the post-annealing treatments. Well-defined periodic structures can be achieved with 2.5 nm thick SiO 2 sublayers. It is shown that the size of formed nano-crystalline Si is about 3 nm. Room temperature electroluminescence can be observed and the spectrum contains two luminescence bands located at 650 nm and 520 nm. In order to improve the hole injection probability, p-i-n structures containing a nanocrystalline Si/SiO 2 luminescent layer were designed and fabricated on different p-type substrates. It is found that the turn-on voltage of p-i-n structures is obviously reduced and the luminescence intensity increases by 50 times. It is demonstrated that the use of a heavy-doped p-type substrate can increase the luminescence intensity more efficiently compared with the light-doped p-type substrate due to the enhanced hole injection.
a-Si/SiO2
multilayers with different a-Si sublayer thicknesses were prepared by plasma enhanced
chemical vapour deposition (PECVD). An intermediate phase silicon structure
(IPSS), which is intermediate in order between the continuous random network
amorphous phase and the well ordered crystalline phase, was discovered in the a-Si
sublayers near the crystallization onset temperatures through Raman scattering and
cross-section high resolution transmission electron microscopy (HRTEM). A strong broad
photoluminescence (PL) band, consisting of two peaks centred at 773 nm and
863 nm respectively, was observed with the formation of the IPSS. Based on the
analysis of the temperature dependence of PL, the strong PL emission bands
centred at 863 and 773 nm are ascribed to the structural defects inside the IPSS and
Si = O
at the surface of the IPSS, respectively.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.