Characteristics of Amorphous Silicon Nitride Films Deposited by LF-PECVD from SiH_4/N_2

Amorphous silicon nitride films were deposited by low-frequency plasma-enhanced chemical vapor deposition（LF-PECVD） using silane and nitrogen as precursors. Characteristics such as deposition rate, surface morphology, and chemical composition were measured by spectroscopic ellipsometry（SE）, atomic force mieroscope（AFM） and x-ray photoelectron spectroscopy（XPS）. It was shown that amorphous silicon nitride film could be prepared by LF-PECVD with good uniformity and even surface. The XPS result indicated that a small quantity of oxygen was involved in the sample, which was discussed in this paper.

一种新型衍射超分辨光学器件

提出了一种提高通过光学系统的部分光线的空间频率 ,来提高系统分辨率的新型衍射超分辨光学器件。该器件通过把部分低频光线移到高频带 ,使得艾里斑的主斑变小 ,同时焦深也得到了延长。模拟计算结果表明 ,在中心峰值强度相等的条件下 ,用该器件所获得的超分辨效果比目前最好的纯相位型超分辨光阑要好。