| 摘要 |
A method for forming shallow trench isolation is disclosed. A pad oxide layer is formed on a substrate, and a mask layer is deposited on the pad oxide layer. The mask layer and the pad oxide layer are patterned to expose the substrate. Thereafter, the exposed substrate is subsequently etched to form a shallow trench. A lining oxide layer is formed by thermal oxidation on the shallow trench sidewalls. Afterwards, a silicon-rich oxide layer is deposited by high-density chemical vapor deposition (HDPCVD) process on the substrate and the shallow trench. Next, a silicon oxide layer is formed using the same HDPCVD process on the silicon-rich layer. Subsequently, an excess portion of silicon oxide and the silicon-rich oxide over the silicon nitride layer are effectively removed using some standard semiconductor processes. Eventually, the mask layer is removed and the pad oxide layer is stripped to form silicon oxide plug served as shallow trench isolation.
|
