氮化硅薄膜的热丝化学气相沉积法制备及微结构研究

发布时间：2018-02-20 01:47

本文关键词： 热丝化学气相沉积薄膜氮化硅化学键结构　出处：《硅酸盐通报》2017年02期 　论文类型：期刊论文

【摘要】：采用热丝化学气相沉积法,以SiH_4、NH_3、N_2为反应气源,通过改变氮气流量沉积氮化硅薄膜。通过紫外-可见(UV-VIS)光吸收谱、傅里叶红外透射光谱(FTIR)、X射线衍射谱(XRD)等测试手段对薄膜的光学带隙、键合特性及晶相进行表征与分析。结果表明:薄膜主要表现为Si-N键合结构,当N_2流量从20 sccm变化到40 sccm时,热丝能够充分的分解N_2,薄膜中N原子过量,其周围的Si和H能充分的与N结合。但由于N_2的解离能较高,当N_2流量高于40 sccm时,氮气在反应过程中对薄膜内的氮原子反而起到了稀释作用,薄膜的有序程度增大,光学带隙减小,致密性降低。当氮气流量达到150 sccm时,在2θ为69.5°处出现了晶化β-Si_3N_4的尖锐衍射峰,其择优取向沿(322)晶向,且Si_3N_4晶粒显著增大。因此,氮气流量对薄膜中的氮含量有显著影响,适当的增加氮气流量有利于制备出优质含有小晶粒β-Si_3N_4薄膜。
[Abstract]:Silicon nitride thin films were deposited by hot-filament chemical vapor deposition with SiH4H _ 4NH _ 3N _ 2 as reaction gas source and by changing nitrogen flow rate. UV-Vis absorption spectra were used. Fourier transform infrared transmission spectroscopy (FTIR) and X-ray diffraction (XRD) were used to characterize and analyze the optical band gap, bonding characteristics and crystal phase of the films. The results show that the films mainly exhibit Si-N bonding structure, and when N _ 2 flux varies from 20 sccm to 40 sccm, The hot filament can fully decompose N _ 2, the N atom in the film is excessive, and the Si and H around it can fully bind to N. However, because of the high dissociation energy of N _ (2), when the flow rate of N _ (2) is more than 40 sccm, Nitrogen dilutes the nitrogen atoms in the film during the reaction. The order of the film increases, the optical band gap decreases and the densification decreases. When the nitrogen flow rate reaches 150 sccm, A sharp diffraction peak of 尾 -Si3N _ 4 was observed at 2 胃 = 69.5 掳. The preferred orientation of 尾 -Si _ 3N _ 4 was along the direction of 322), and the grain size of Si_3N_4 increased significantly. Therefore, nitrogen flow rate had a significant effect on the nitrogen content in the films. Proper increase of nitrogen flow rate is beneficial to the preparation of high quality 尾 -SiTi3N4 thin films containing small grains.
【作者单位】：内蒙古师范大学物理与电子信息学院功能材料物理与化学自治区重点实验室;
【基金】：国家自然科学基金资助项目(51262022)
【分类号】：TN304.2

【相似文献】