专利快速检索-快速检索全球专利，免费商用专利数据库-IPRDB

1. 发明授权

US4897364A Method for locos isolation using a framed oxidation mask and a polysilicon buffer layer 失效
标题翻译：使用框架氧化掩模和多晶硅缓冲层进行定位隔离的方法
公开(公告)号：US4897364A
公开(公告)日：1990-01-30
申请号：US315866
申请日：1989-02-27
申请人： Bich-Yen Nguyen , Philip J. Tobin , Shih-Wei Sun , Michael Woo
发明人： Bich-Yen Nguyen , Philip J. Tobin , Shih-Wei Sun , Michael Woo
IPC分类号： H01L21/32 , H01L21/762
CPC分类号： H01L21/32 , H01L21/76216
摘要： An improved LOCOS device isolation method for forming a field oxide is disclosed having the advantage of controllable and uniform sidewall framing of a nutride oxidation mask. This advantage is achieved by the use of a polysilicon layer overlying a nitride mask with the polysilicon providing an etching endpoint during the anisotropic etching used for sidewall formation. In one embodiment of the invention a silicon substrate is provided having a pad oxide formed on its surface and a first polysilicon stress-relief buffer layer formed overlying the pad oxide. A first nitride layer, to be used for oxidation masking during field oxide growth, is deposited overlying the first polysilicon layer. Next, a second polysilicon, etch-resistant buffer layer is deposited overlying the first nitride layer.The first nitride layer and second polysilicon layer are patterned by conventional lithography while the first polysilicon and pad oxide layers remained unpatterned. A second nitride layer is deposited overlying the patterned second polysilicon layer and exposed regions of the first polysilicon layer. Sidewalls are formed on the edges of the patterned first nitride and second polysilicon layers by anisotropically etching the second nitride layer using the first and second polysilicon layers as etching endpoints. Finally, the field oxide is grown by conventional methods. The grown field oxide exhibits reduced bird's beak length, and the resulting field separation is not limited by optical lithography resolution.
摘要翻译：公开了一种用于形成场氧化物的改进的LOCOS器件隔离方法，其具有可控制和均匀的叶片氧化掩模侧壁框架的优点。该优点通过使用覆盖氮化物掩模的多晶硅层来实现，其中多晶硅在用于侧壁形成的各向异性蚀刻期间提供蚀刻终点。在本发明的一个实施例中，提供硅衬底，其具有在其表面上形成的衬垫氧化物和形成在衬垫氧化物上的第一多晶硅应力释放缓冲层。在场氧化物生长期间用于氧化掩蔽的第一氮化物层沉积在第一多晶硅层上。接下来，沉积覆盖第一氮化物层的第二多晶硅，耐蚀刻缓冲层。第一氮化物层和第二多晶硅层通过常规光刻图案化，而第一多晶硅和衬垫氧化物层保持未图案化。第二氮化物层沉积在图案化的第二多晶硅层和第一多晶硅层的暴露区域上。通过使用第一和第二多晶硅层作为蚀刻终点通过各向异性蚀刻第二氮化物层，在图案化的第一氮化物和第二多晶硅层的边缘上形成侧壁。最后，通过常规方法生长场氧化物。生长的田间氧化物表现出减少的鸟的喙长度，并且所得到的场分离不受光学光刻分辨率的限制。

IPRDB

热门服务

关于我们

友情链接

联系方式