SiN_x和SiN_x/SiO_x薄膜的荧光和红外吸收光谱研究

Investigation on the photoluminescence and infrared absorption spectra of SiNx and SiNx/SiOx films

采用射频磁控溅射法在Si(100)和含有SiOx缓冲层的Si(100)上制备SiNx薄膜。直接生长在Si(100)的SiNx薄膜几乎不发光;而SiNx/SiOx薄膜在650℃以上的高温热处理后有非常强的光致发光,当退火温度为800oC时发光强度达到最高。傅立叶红外吸收研究表明,直接生长在Si(100)的SiNx薄膜在退火后氧化程度略有增加;而SiNx/SiOx薄膜在高温热处理后氧化程度明显升高,但过高温度的退火会导致Si-N键显著减少。分析认为SiNx/SiOx薄膜的发光与Si-N键和Si-O键密切相关。

The SiNx films with or without SiOx buffer were deposited on Si（100）. Very weak photoluminescence （PL） was observed for the SiNx film directly grown on Si（100）. While for the SiNx/SiOx film, strong visible PL is achieved with annealing temperature above 650 ℃, and optimal PL is obtained at 800℃. Fourier-Transform Infrared Transmission （FTIR） spectra reveal that strong PL is directly related to the content of the Si-N and Si-O bonds in the SiNx films. For the SiNx film directly grown on Si （100）, the oxidation increases little after high-temperature anneal. The introduction of SiOx buffer can significantly increase the oxidation, but too high temperature will cause the number of Si-N bond to strongly decrease.