等离子体蚀刻多晶硅深沟道研究

Study of Plasma Etch on Deep Trench Silicon Polysilicon

等离子体蚀刻硅深沟道用作存贮器件的储存电容有非常重要的作用,就等离子体在微电子制造领域中蚀刻二氧化硅,多晶硅的原理和如何控制形状(profile)和深沟道的深度做了研究,解释了HBr,NF3,He_30%O2气体,压力对蚀刻速率,Si/SiO2蚀刻选择比的影响.结果表明:蚀刻率随HBr流量的增大而增大,压力和侧壁保护气体He_30%O2控制着整个蚀刻图形.

Plasma etch of silicon is utilized in forming deep trenches which are used as storage capacitors in many types of memory applications. The plasma etch theory on oxide and polysilicon in microelectronics manufacturing has been investigated. And this paper explained how to control the profile and the trench depth and the effect of HBr, NF3 , He_O2 gas and pressure on etch rate and Si/SiO2 selectivity. The result indicates that with the increase of HBr gas flow, the etch rate would be increased; and the pressure and sidewall passivation gas He_O2 would control the deep trench profile.