A novel shallow trench isolation with mini-spacer technology

A new shallow trench isolation (STI) process wit a mini-spacer at the maski ng nitride sidewall before silicon trench etching was proposed. With this m ini-spacer, thicker corner liner oxide and a T-shaped trench oxide can be f ormed simultaneously. The issue of oxide-recess at STI corner can be effect ively reduced and larger process window for subthreshold kink free device w ere obtained. The isolation capability and junction integrity were both imp roved as compared with those of the conventional STI process. Reverse narro w width effect as well as gate oxide integrity were also improved. This tec hnology was employed for 0.13 mu m complementary metal oxide silicon (CMOS) device fabrication.