摘要 |
A method for forming a shallow trench isolation using a SiON anti-reflective coating which eliminates water spot defects. The method begins by providing a substrate. A pad oxide layer is formed over the substrate. A silicon nitride layer is formed on the pad oxide layer. A silicon oxynitride layer is formed on the silicon nitride layer. A photoresist mask, having an opening, is formed over the silicon oxynitride layer. The silicon oxynitride layer, the silicon nitride layer, the pad oxide layer, and the substrate are etched through the opening, forming a trench. The photoresist mask is removed. In the key step, the silicon oxynitride layer is removed. Then, a thin silicon oxide layer is grown and a silicon oxide layer is deposited and planarized to form a shallow trench isolation.
|