Method for filling the trenches of shallow trench isolation (STI) regions

摘要

A method for manufacturing a shallow trench isolation (STI) region with a high aspect ratio is provided. A semiconductor substrate is provided with a trench. A first dielectric layer is formed lining the trench. A second dielectric layer is formed filling the trench over the first dielectric layer. In some embodiments, before forming the second dielectric layer, ions are implanted into an implant region of the first dielectric layer that extends along and is limited to a lower region of the trench. In alternative embodiments, after forming the second dielectric layer, an ultraviolet curing process is performed to the second dielectric layer. With the second dielectric layer formed and, in some embodiments, the ultraviolet curing process completed, an annealing process is performed to the second dielectric layer. A semiconductor structure for a STI region is also provided.