公开(公告)号：US5677234A

公开(公告)日：1997-10-14

申请号：US665294

申请日：1996-06-18

申请人： Bon-young Koo ,  Byung-hong Chung ,  Hee-seok Kim ,  Yun-gi Kim

发明人： Bon-young Koo ,  Byung-hong Chung ,  Hee-seok Kim ,  Yun-gi Kim

IPC分类号： H01L21/316 ,  H01L21/32 ,  H01L21/76

CPC分类号： H01L21/32

摘要： Methods of forming semiconductor device active regions include the steps of forming a buffer layer containing a material susceptible to oxidation, such as polycrystalline or amorphous silicon, on a semiconductor substrate. To inhibit any native oxide film on the buffer layer from facilitating the formation of field oxide isolation regions having bird's beaks, the native oxide film is converted to a nitrogen containing film, such as silicon oxynitride, by nitrating the native oxide film. The silicon oxynitride film can be formed by exposing the oxide film to a nitrogen containing plasma, implanting nitrogen ions into the oxide film or annealing the oxide film in a nitrogen containing atmosphere, for example. During the nitrating step, chemically active oxygen in the native oxide film becomes bound to the nitrogen incorporated therein. A top oxidation resistant layer containing silicon nitride can then be formed on the nitrated surface of the buffer layer and used as an oxidation mask during a subsequent step of oxidizing the buffer layer to form field oxide isolation regions. By binding chemically active oxygen to nitrogen during the nitrating step, lateral oxidation under the top oxidation resistant layer is inhibited by limiting the lateral transport of chemically active oxygen. The masking properties of the top oxidation resistant layer can therefore be enhanced and utilized to form field oxide isolation regions having short or nonexistent bird beak's.

摘要翻译： 形成半导体器件有源区的方法包括在半导体衬底上形成含有易于氧化的材料（例如多晶或非晶硅）的缓冲层的步骤。 为了抑制缓冲层上的任何自然氧化膜促进形成具有鸟喙的场氧化物隔离区，通过硝化天然氧化物膜将天然氧化物膜转化成含氮膜如氮氧化硅。 氧氮化硅膜可以通过将氧化物膜暴露于含氮等离子体，将氮离子注入到氧化膜中或者在含氮气氛中退火氧化膜来形成。 在硝化步骤期间，天然氧化膜中的化学活性氧与结合在其中的氮结合。 然后可以在缓冲层的硝化表面上形成含有氮化硅的顶部耐氧化层，并且在随后的氧化缓冲层的步骤中用作氧化掩模以形成场氧化物隔离区。 通过在硝化步骤期间将化学活性氧与氮结合，通过限制化学活性氧的横向运输来抑制顶部抗氧​​化层下的侧向氧化。 因此，顶部抗氧化层的掩蔽性能可以被增强并且用于形成具有短或不存在的鸟喙的场氧化物隔离区。