公开(公告)号：US5670018A

公开(公告)日：1997-09-23

申请号：US430011

申请日：1995-04-27

申请人： Elke Eckstein ,  Birgit Hoffman, deceased ,  Edward William Kiewra ,  Waldemar Walter Kocon ,  Marc Jay Weiss

发明人： Elke Eckstein ,  Birgit Hoffman, deceased ,  Edward William Kiewra ,  Waldemar Walter Kocon ,  Marc Jay Weiss

IPC分类号： C23F4/00 ,  H01L21/302 ,  H01L21/3065 ,  H01L21/3213 ,  H01L21/8242 ,  H01L27/108

CPC分类号： H01L21/32137 ,  Y10S438/963

摘要： A back end of the line dry etch method is disclosed. Etching of a mask oxide and temporary (sacrificial) silicon mandrel occurs following the formation of gate stacks and tungsten studs. The mask oxide is etched selectively to tungsten and silicon through the use of a polymerizing oxide etch. The silicon is etched selectively to both silicon nitride, silicon oxide, and tungsten. The process removes the silicon mandrel and associated silicon residual stringers by removing backside helium cooling, while using HBr as the single species etchant, and by adjusting the duration, the pressure, and the electrode gaps during the silicon etch process. The silicon may be undoped polysilicon, doped polysilicon, or single crystal silicon.

摘要翻译： 公开了线干法蚀刻方法的后端。 掩模氧化物和临时（牺牲）硅心轴的蚀刻在栅堆叠和钨钉形成之后发生。 通过使用聚合氧化物蚀刻，对钨和硅选择性地蚀刻掩模氧化物。 硅被选择性地蚀刻到氮化硅，氧化硅和钨两者。 该方法通过去除背面的氦冷却，同时使用HBr作为单一种类蚀刻剂，并通过在硅蚀刻工艺期间调节持续时间，压力和电极间隙来移除硅心轴和相关硅残余桁条。 硅可以是未掺杂的多晶硅，掺杂多晶硅或单晶硅。