| 摘要 |
<p>A method for fabricating a semiconductor device is provided to avoid generation of seams or voids in forming a polysilicon layer and prevent residue generated by seams or voids from being formed by mixedly using a process for forming a floating gate of an STI(shallow trench isolation) isolation layer and a process for forming self-aligned floating gate. After a pattern composed of a screen oxide layer, a nitride layer, a buffer oxide layer and a silicon oxynitride layer is formed on a semiconductor substrate(100), a part of the substrate is etched to form a trench by using the pattern as a mask. After an HDP(high density plasma) oxide layer is formed on the resultant structure to fill the trench, a planarization process is performed until the nitride layer is exposed. After the nitride layer is removed to form an isolation layer(116) having a nipple, a tunnel oxide layer(120) is formed on the resultant structure. A polysilicon layer is formed on the resultant structure to fill a gap between the isolation layers and is planarized. An organic ARC and a photoresist pattern are formed on the planarized polysilicon layer. By using the photoresist pattern as a mask, the polysilicon layer is etched to form a gate. A hard mask layer composed of the nitride layer, the buffer oxide layer and the silicon oxynitride layer is formed.</p> |
