Hydrogenated nanocrystalline silicon carbide films synthesized by ECR-CVD and its intense visible photoluminescence at room temperature

Hydrogenated nanocrystalline silicon carbide (nc-SiC:H) films, which contai n nanosize SIC crystals embedded in a-SiC:H matrix were fabricated by the e lectron cyclotron resonance chemical vapor deposition (ECR-CVD) technique. It was found that under the deposition conditions of strong hydrogen diluti ons and high microwave power, films containing SiC nanocrystallites embedde d in an SiC:H amorphous matrix could be obtained, as shown by the use of hi gh resolution transmission electron microscopy. Infrared absorption, Raman scattering and X-ray photoelectron spectroscopy studies have also confirmed the successful fabrication of these nc-SiC:H films. Very strong photolumin escence in the visible range with a peak energy of 2.64 eV could be observe d from these films at room temperature. Temporal evolution of the PL at the peak emission energy exhibits a bi-exponential decay process with lifetime s that are in the order of ps and ns. The strong light emission and short P L lifetimes observed strongly suggest that the radiative recombination is a result of direct optical transitions in the SIC nanocrystallites. The resu lts obtained in this study show that these nc-SiC:H films are potentially s uitable as active layers in large area flat panel displays. (C) 2000 Elsevi er Science B.V. All rights reserved.