| 摘要 |
A method for preparing a shallow trench isolation structure with the stress of its isolation oxide being tuned by ion implantation comprises: step a: forming a protective layer on a semiconductor substrate; step b: forming trenches for isolating PMOS active regions and NMOS active regions on the semiconductor substrate and the protective layer; step c: forming a filling material layer in the trenches, so that the trenches are fully filled with the filling material layer to form shallow trench isolation structures. The advantageous is that, as for a device where a HARP process is applied to its shallow trench isolation, the stress in the STI can be tuned so as to be changed from tensile stress into compressive stress by performing ion implantation to the STI around the PMOS, therefore the stress state of the PMOS channel region may be changed and the performance thereof is improved.
|
