| 摘要 |
A method for aliging a shallow trench isolation is provided. An aligning mark which is deeper than a prior technique is formed in a provided substrate. A trench is formed and an aligning trench is formed in the position over the aligning mark. A thick oxide layer is deposited on the semiconiductol substrate, in the trench and in the aligning trench. After a portion of the thick oxide layer removed, another portion of the thick oxide layer is removed by etching back. A gate oxide layer is formed on a substrate comprising the trench and the aligning trench. A polysilicon layer with the step-height profile in the position over the aligning mark is formed on the gate oxide layer.
|
