Si top corner damage-free etch process for shallow trench isolation

Shallow trench isolation in large-scale integrated circuits is currently the main isolation method. With the increase of integration density, the requirements of shallow trench isolation technology are getting higher and higher. In this paper, the problem of sidewall damage in shallow trench isolation (STI) etching is solved by adjusting the selection of process parameters. In the experiment, the formation of polymer is controlled by changing the content of O2 to solve the problem of Si top damage. After solving and optimizing the process difficulties of shallow trench isolation in this article, the performance of the obtained isolation structure fully meets the requirements of large-scale mass production of logic device technology.