Hydrogenated amorphous silicon nitride (a-SiNx:H) films have been deposited by helicon wave plasma enhanced chemical vapor deposition (HWP-CVD), the effect of SiH4/N2 rate on the properties of the samples is systematically studied, and the critical experiment condition is obtained under which a-SiNx:H films with different compositions are deposited. The structure properties of a-SiNx:H are characterized and analyzed by using ellipsometry, Fourier Transform Infrared (FTIR) spectroscopy and X-ray Photoelectron Spectroscopy (XPS), all the results suggest that the films with the structure of silicon dots/clusters embedding in silicon nitride matrix can be obtained by controlling the HWP-CVD conditions properly. Based on the above work, the optical absorption and photoluminescence (PL) properties of a-SiNx:H films with different compositions are studied through Ultraviolet-Visible spectroscopy (UV-VIS) and time-resolved photoluminescence (tr-PL), the dependence of PL intensity decay on emission photon energy is found, the luminescence mechanism of nanosilicon embedded in silicon nitride matrix is presented, finally, the effective approaches to improving the luminescence efficiency of a-SiNx: H films are discussed.
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