中文摘要：

采用等离子体化学气相沉积法（PECVD）制备了三种不同化学计量比的富Si的SiN薄膜，并对其光致发光及电致发光性能进行了研究。研究发现，随着Si含量的增加，薄膜的光致发光峰位从460nm红移到610nm，且半高宽不断增加；而薄膜的电致发光峰位并没有随着Si含量的改变而变化，始终处于600nm附近，这主要是由于富Si的SiN薄膜的光致发光与电致发光的机理是不同的。光致发光来源于SiN薄膜缺陷态能级之间辐射复合，而电致发光则是由注入的载流子先迟豫到较低的缺陷态能级，然后经过辐射复合而得到。

英文摘要：

Si-rich SiN films with different excess Si concentrations were deposited by PECVD under different NH3/SiH4 gas flow ratios. With the increase of the Si concentrations the peak of PL spectra shifts from 460 nm to 610 nm, but the peak of EL spectra remains at 600 nm. The observed PL can be explained as the recombination via defect states in silicon nitride, while the EL can be attributed to the relaxation of injected carriers down the lower defect states before recombination due to their longer recombination lifetime.