Method of forming isolated regions of oxide
AssigneeSGS-Thomson Microelectronics S.A.
InventorsRobert Hodges, Frank Bryant
Life of this patent
Estimating the term…
Abstract
A method is provided for forming isolated regions of oxide of an integrated circuit, and an integrated circuit formed according to the same. A pad oxide layer is formed over the integrated circuit. A nitrogen doped polysilicon layer is formed over the pad oxide layer. A thick nitride layer is then formed over the nitrogen doped polysilicon layer. An opening is formed in the nitride layer and the nitrogen doped polysilicon layer exposing a portion of the pad oxide layer. The nitrogen doped polysilicon layer is annealed encapsulating the polysilicon layer in silicon nitride. A field oxide region is then formed in the opening.
Claims18
A method of forming isolated regions of oxide of an integrated circuit comprising the steps of:
- forming a pad oxide layer over the integrated circuit;
- forming a polysilicon buffer layer over the pad oxide layer;
- implanting nitrogen into the polysilicon buffer layer;
- forming a nitride layer over the polysilicon buffer layer;
- applying and patterning a photoresist layer over the nitride layer to form an opening exposing a portion of the nitride layer;
- etching the nitride layer and the polysilicon buffer layer through the opening exposing a portion of the pad oxide layer;
- annealing the polysilicon buffer layer encapsulating the polysilicon buffer layer in silicon nitride;
- and,
- forming a field oxide region in the opening.
A method of forming isolated regions of oxide of an integrated circuit comprising the steps of:
- forming a pad oxide layer over the integrated circuit;
- forming a nitrogen doped polysilicon layer over the pad oxide layer;
- forming a nitride layer over the nitrogen doped polysilicon layer;
- forming in the nitrogen doped polysilicon and nitride layers exposing a portion of the pad oxide layer;
- annealing the nitrogen doped polysilicon layer to encapsulate the nitrogen doped polysilicon layer in silicon nitride;
- and,
- forming a field oxide region in the opening.
Dependencies are inferred from the claim text.