低压化学气相淀积低应力氮化硅工艺研究  

Research on Low Stress Silicon Nitride by Using Low Pressure Chemical-Vapor Deposition Process

作　　者：王敬轩[1] 商庆杰[1] 杨志[1] WANG Jingxuan;SHANG Qingjie;YANG Zhi(China Electronics Technology Group Corporation No.13 Research Institute,Shijiazhuang 050000,China)

机构地区：[1]中国电子科技集团公司第十三研究所,石家庄050000

出　　处：《电子与封装》2021年第8期94-98,共5页Electronics & Packaging

摘　　要：微机械加工(Micro-Electro Mechanical System,MEMS)工艺中常需要应用到低应力氮化硅作为结构层或钝化层材料,以降低圆片的翘曲。通过采用低压化学气相淀积工艺(Low Pressure Chemical-Vapor Deposition,LPCVD),优化工艺中反应气体流量比,可以得到应力低于200 MPa的氮化硅薄膜。针对工艺中存在的片间应力以及薄膜厚度均匀性差的问题,采用二次离子质谱测试(Secondary Ion Mass Spectroscopy,SIMS)的方式,分析出反应气体的消耗造成的反应气体比例变化是引起该问题的主要因素。通过优化工艺参数,得到了片间应力在100~150 MPa之间、厚度均匀性5%以内的低应力氮化硅薄膜,可实现50片/炉的工艺能力,可批量应用于MEMS工艺中。In order to flatten the bow of wafers,low stress silicon nitride is often used in the micro-electro mechanical system(MEMS)as structural layer materials or passivation films.The silicon nitride films whose stress are under 200 MPa pascal through optimizing the ratio of the reaction gases in low pressure chemical-vapor deposition are obtained.Bad wafer to wafer non-uniformity of films'stress and thickness is an important process problem.The change of ratio caused by the consumption of the reaction gases is the main factor in the method of using secondary ion mass spectroscopy(SIMS).By optimizing the process parameters,the silicon nitride films whose wafer to wafer stress is between 100 MPa and 150 MPa pascal and thickness non-uniformity is below 5%.And the process capability of 50 wafers per furnace is realized,which can be used in micro-electro mechanical system process in the future.

关 键 词：微机械加工 低压化学气相淀积 低应力氮化硅 均匀性 

分 类 号：TN304.9[电子电信—物理电子学]