Method for reducing stress of sidewall oxide layer of shallow trench isolation
AssigneeMacronix International Co., Ltd.
InventorShu-Ya Hsu
Life of this patent
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Abstract
The invention utilizes introductions of oxygen and hydroxyl to perform an in situ steam generated (ISSG) process to anneal and reoxidize a conventional sidewall oxide layer in a shallow trench isolation. The ISSG annealing process renders the conventional sidewall oxide layer much less stress. The electrical property of the active regions and the isolation quality between the active regions can be assured.
Claims19
A method for reducing a stress of a sidewall oxide layer of a shallow trench isolation, said method comprising:
- providing a substrate having a first dielectric layer thereon and a second dielectric layer over said first dielectric layer;
- forming a trench into said substrate;
- forming a sidewall oxide layer on the sidewall and bottom of said trench;
- and
- performing an in situ steam generated process comprising introducing hydroxyl to anneal said sidewall oxide layer.
A method for reducing a stress of a sidewall oxide layer of a shallow trench isolation, said method comprising:
- providing a substrate having a silicon dioxide layer thereon and a silicon nitride layer over said silicon dioxide layer;
- forming a trench into said substrate;
- forming a sidewall oxide layer on the sidewall and bottom of said trench;
- and
- performing an in situ steam generated process comprising introducing oxygen and hydroxyl to anneal and reoxidize said sidewall oxide layer at a temperature of from about 700° C. to about 1200° C.
A method for reducing a stress of a sidewall oxide layer of a shallow trench isolation, said method comprising:
- providing a substrate having a silicon dioxide layer thereon and a silicon nitride layer over said silicon dioxide layer;
- forming a trench into said substrate by a dry etching process;
- forming a sidewall oxide layer on the sidewall and bottom of said trench;
- and
- performing an in situ steam generated process comprising introducing oxygen and hydroxyl to anneal and reoxidize said sidewall oxide layer at a temperature of from about 700° C. to about 1200° C. in a rapid thermal annealing chamber.
Dependencies are inferred from the claim text.