公开(公告)号：US06468853B1

公开(公告)日：2002-10-22

申请号：US09641389

申请日：2000-08-18

申请人： Palanivel Balasubramanian ,  Yelehanka Ramachandramurthy Pradeep ,  Chivkula Subrahmanyam ,  Narayanan Balasubramanian

发明人： Palanivel Balasubramanian ,  Yelehanka Ramachandramurthy Pradeep ,  Chivkula Subrahmanyam ,  Narayanan Balasubramanian

IPC分类号： H01L218238

CPC分类号： H01L21/76235

摘要： A structure and a process for manufacturing semiconductor devices with improved oxide coverage on the corners of a shallow trench isolation structure is described. The STI trench is etched using a pad oxide and silicon nitride layers as patterning elements. After trench etch, a thin conformal layer of either amorphous, epitaxial or polysilicon is deposited over the silicon nitride and within the trench and annealed. Where the silicon has been deposited on the silicon bottom and sides of the open trench, the annealing effectively forms a single crystal or epitaxial silicon. Next a silicon oxide liner is grown over the conformal silicon layer. The trench is then filled with silicon oxide, the structure is planarized by either chemical mechanical polishing or etching, and the nitride and pad oxide is removed This leaves a polysilicon film on the vertical edges of the filler oxide which extends slightly above the surface of the silicon substrate. A thermal oxidation step is performed converting the poly film into silicon oxide which slightly extends the STI field oxide into the active device region eliminating any reduced oxide coverage or oxide recesses in the corner regions.

摘要翻译： 描述了在浅沟槽隔离结构的角上制造具有改善的氧化物覆盖的半导体器件的结构和工艺。 使用衬垫氧化物和氮化硅层作为图案化元件来蚀刻STI沟槽。 在沟槽蚀刻之后，非晶，外延或多晶硅的薄的共形层沉积在氮化硅上并在沟槽内并退火。 当硅沉积在开口沟槽的硅底部和侧面上时，退火有效地形成单晶或外延硅。 接下来，在保形硅层上生长氧化硅衬垫。 然后用氧化硅填充沟槽，通过化学机械抛光或蚀刻对该结构进行平面化，并且去除氮化物和衬垫氧化物。在填充氧化物的垂直边缘上留下多晶硅膜，其在 硅衬底。 执行热氧化步骤，将多晶硅膜转化为将STI场氧化物稍微延伸到有源器件区域中的氧化硅，消除角区域中任何减少的氧化物覆盖或氧化物凹陷。