Deveiopment of Room Temperature Deposition Process of Silicon Nitride Film by Low Frequency Plasma CVD.

低频等离子体CVD 氮化硅薄膜室温沉积工艺的发展。

基本信息

批准号：
61850049
负责人：
SHIMOZUMA Mitsuo
金额：
$ 2.75万
依托单位：
College of Medical Technology, Hokkaido University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Developmental Scientific Research
财政年份：
1986
资助国家：
日本
起止时间：
1986 至 1987
项目状态：
已结题

项目摘要

Silicon nitride films are being used extensively in the semiconductor technology for interlayer insulation and device surface passivation. Stoichiome-tric silicon nitrode Si_3n_4 can be deposited by thermal deposition at about 900 ゜C, and nearly stoichimetric silicon nitride films have been deposited by the high frequency plasma CVD method at low substrate temperature (200-300゜c). The purpose of the present study is to deposite of silicon nitride films at room temperature using low frequency(50Hz) plasma CVD with silane and nitrogen mixtures. The results obtained may be summarized as below.1) Silicon nitride films have been deposited by low frequency(50Hz) plasma CVD using a nitsogen and silane mixture at room temperature. To deposit high quality silicon nitride, the silane fraction in the nitrogen and silane mixture has to be less than 5%.2) The refractive index, breakdown field strenght and resistivity of the obtained silicon nitride film were 2.0, 1.2 x 1 0^1 V/cm and 6 x 1 0^<15> cm, respectively.3) The distribution of film thickness on 5 inches Si wafer was 1000 <plus-minus> 30 <Ang>. 4) Fixed charge density and surface state density of Al/SiNx/SiO_2 /Si(MNOS) were about 1.5 x 1 0^<11> cm^<-2> and 8 x 10^<10> cm^<-2> ev^<-1> , respectively. substrate temperature dependence of the film properties were observed, and as high the temperature(<200゜c) is, the films become Si tich. However electrical properties were not changed.5) The emission.intensity from silicon and nitrogen neutral and ionized molecule in nitrogen and silane mixture plasma with low frequency(50Hz) is large compared with that from RF(13.56MHz) plasma.6) Since low frequency plasma can generate high electron energy plasma, which is required for good silicon nitride formation, high quality silicon nitride films can be grown without any assistance from heating of the substrate.

氮化硅薄膜主要用于半导体技术中的层间绝缘和器件表面钝化，化学计量氮化硅Si_3n_4可以通过900℃左右的热沉积来沉积，并且近化学计量氮化硅薄膜已经通过高频沉积。低衬底温度（200-300℃）下的等离子体CVD方法本研究的目的是沉积氮化硅薄膜。在室温下使用硅烷和氮气混合物进行低频（50Hz）等离子体CVD 结果可总结如下。1）在室温下使用氮和硅烷混合物通过低频（50Hz）等离子体CVD 沉积氮化硅薄膜。为了沉积高质量的氮化硅，氮气和硅烷混合物中的硅烷含量必须小于5%。2)折射率、击穿场强和电阻率。所得氮化硅膜的厚度分别为2.0、1.2×1 0^1 V/cm、6×1 0^<15>cm。3)5英寸Si晶片上的膜厚分布为1000<正负> 30 <Ang> 4) Al/SiNx/SiO_2 /Si(MNOS)的固定电荷密度和表面态密度约为1.5 x 1。分别观察到 0^<11> cm^<-2> 和 8 x 10^<10> cm^<-2> ev^<-1> 薄膜特性的基板温度依赖性，并且温度相同（ <200゜c)时，薄膜变为Si，但电性能没有改变。5) 氮和硅烷混合物等离子体中硅和氮中性和电离分子的发射强度。频率（50Hz）与射频（13.56MHz）等离子体相比要大。6）由于低频等离子体可以高产生电子能等离子体，这是良好氮化硅形成所必需的，因此可以在没有任何辅助的情况下生长高质量氮化硅薄膜来自基材的加热。