Joshua H Robbins

US Patent:

62287419, May 8, 2001

Filed:

Jan 11, 1999

Appl. No.:

9/228583

Inventors:

Shawn T. Walsh - Richardson TX
John E. Campbell - Plano TX
James B. Friedmann - Dallas TX
Thomas M. Parrill - North Andover MA
Joshua J. Robbins - Dallas TX
Byron T. Ahlburn - Plano TX
Sue Ellen Crank - Coppell TX

Assignee:

Texas Instruments Incorporated - Dallas TX

International Classification:

H01L 2176

US Classification:

438400

Abstract:

A method is given for removing excess oxide from active areas after shallow trench isolation, without the use of chemical-mechanical polishing. A nitride mask protects active areas during the etch of isolation trenches. The trenches are filled with oxide, using high density plasma deposition, which simultaneously etches, providing a sloping contour around the isolation trenches. A further layer of nitride is used to provide a cap over the trench which seals to the underlying layer of nitride. The cap layer of nitride receives a patterned etch to remove the cap only over the active areas. This allows a selective etch to remove the excess oxide, which can be followed by a selective etch to remove the nitride layers.