Analysis of the Local Bonding Structure in Silicon Nitride (Oxide) Films Deposited by Plasma-Enhanced CVD in Terms of a Charge-Transfer Model

根据电荷转移模型分析等离子体增强 CVD 沉积的氮化硅（氧化物）薄膜的局部键合结构

基本信息

批准号：
05650009
负责人：
HASEGAWA Seiichi
金额：
$ 1.34万
依托单位：
Kanazawa University
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1993
资助国家：
日本
起止时间：
1993 至 1994
项目状态：
已结题

项目摘要

Silicon nitride (SiN_x : H) and Si oxide (SiO_x : H) films are deposited using a plasma-enhanced CVD method, and the vibrational properties, the film stress, and the structure of defects are investigated as a function of the deposition conditions. The results might be summarized as :1) In Si nitride films with a near-stoichiometric composition, the films satisfying all of the low stress, the high break-down strength, and the low etching rate can be obtained as they were deposited under conditions of both high H dilution ratio and high rf power supply. An improvement in properties of the films as insulators can be connected with a change in the local bonding structure : when the density of Si-NH-Si bonds relative to that of N-Si_3 bonds decreases, high quality films can be obtained.2) The oscillator strength for the SiH stretching absorption is a function of the effective charge of the SiH dipole, and the values of the effective charge can be calculated using a charge-transfer model combined with the random bonding model. The calculated values of the oscillator strength for SiN_x : H and SiO_x : H films were in excellent agreement with their experimental values. The frequencies of the SiN and SiO stretching absorption are mainly dominated by the bond length and the bond angle for these bonds. It has been shown that the values of these bond length and bond angle can also connected with the sum of the partial charge on the Si and the N or O atoms.3) The frequency of the SiH bending absorption in SiO_x : H flms, which occur in the range of 500-900 cm^<-1>, was analyzed using a molecular-orbital calculation (MOC) method. Further, the dependence of the electron spin resonance spectra as a function of the film composition, arising from Si dangling bonds, was also analyzed on the basis of the MOC.

使用等离子体增强CVD方法沉积氮化硅(SiN_x:H)和氧化硅(SiO_x:H)薄膜，并研究振动特性、薄膜应力和缺陷结构随沉积条件的变化。结果可概括为：1)在具有接近化学计量组成的氮化硅薄膜中，在沉积条件下可以获得同时满足低应力、高击穿强度和低蚀刻速率的薄膜。高H稀释比和高射频电源。薄膜绝缘体性能的提高与局部键合结构的改变有关：当Si-NH-Si键的密度相对于N-Si_3键的密度降低时，可以获得高质量的薄膜。2) SiH伸缩吸收的振荡器强度是SiH偶极子有效电荷的函数，有效电荷的值可以使用电荷转移模型与随机键合模型相结合来计算。 SiN_x:H和SiO_x:H薄膜的振荡强度的计算值与实验值非常吻合。 SiN 和 SiO 伸缩吸收的频率主要由这些键的键长和键角决定。研究表明，这些键长和键角的值还与Si和N或O原子上的部分电荷之和有关。 3）SiO_x中SiH弯曲吸收的频率：H flms，其中发生在500-900cm ^ -1 的范围内，使用分子轨道计算(MOC)方法进行分析。此外，还基于 MOC 分析了由 Si 悬键引起的电子自旋共振光谱作为膜组成的函数的依赖性。