| 摘要 |
PURPOSE: A method for fabricating an isolation layer of a semiconductor device is provided to reduce a step difference between an active region and a field region by filling and oxidizing polysilicon in a trench by an annealing process using H2 gas in a vacuum chamber. CONSTITUTION: A pad oxide layer and a nitride layer are sequentially formed on a semiconductor substrate. A predetermined region of the nitride layer, the pad oxide layer and the semiconductor substrate is etched to form a trench. The first oxide layer and an undoped polysilicon layer are sequentially formed on the resultant structure. The polysilicon layer is blanket-etched to make the polysilicon layer left only on the sidewall of the trench. An annealing process using H2 gas is performed in a vacuum chamber to make the inside of the trench filled with the polysilicon on the sidewall of the trench. An oxide process is performed on the resultant structure to form the second oxide layer on the polysilicon filled in the trench. The third oxide layer and a spin-on-glass(SOG) layer are sequentially formed on the resultant structure. The SOG layer, the third oxide layer, the nitride layer and the pad oxide layer are sequentially eliminated.
|
