System and method for removal of photoresist and stop layer following contact dielectric etch
First Claim
1. In an overall technique for fabricating an integrated circuit on a wafer having an active device structure, during which fabrication, a patterned layer of photoresist is formed on an overall insulation layer that is itself supported directly on a stop layer that is, in turn, supported directly on the active device structure for using the patterned layer of photoresist in etching holes through the insulation layer to reach an electrical contact that is defined by the active device structure where each electrical contact of a plurality of the electrical contacts is covered by said stop layer and at least some of said electrical contacts include a silicide material and where a plurality of said holes are etched through said overall insulation layer such that one hole is associated with each electrical contact to at least partially expose the stop layer above each electrical contact and where etching of said holes, at least potentially, produces etch related residues, a method comprising:
- stripping said patterned layer of photoresist and said related residues by etching using a first plasma that contains oxygen without substantially removing said stop layer such that the stop layer serves to protect the silicide material from the oxygen; and
after said stripping, etching to remove said stop layer from said contacts using a second plasma that is oxygen free, at least to an approximation, and which second plasma contains hydrogen gas.
1 Assignment
0 Petitions
Accused Products
Abstract
In device fabrication, a photoresist layer is formed on an insulation layer, above a stop layer that is supported directly on an active device structure. Holes are needed through the insulation layer to reach a contact arrangement, defined by the active device structure in which each contact is covered by the stop layer and some of the contacts include a silicide material. A plurality of contact openings are etched through the insulation layer to expose the stop layer above each contact, which may produce etch related residue. The photoresist and residues are then stripped using a first plasma that contains oxygen, without removing the stop layer such that the stop layer protects the silicide material from the oxygen. Thereafter, etching is performed to remove the stop layer from the contacts using a second plasma that is oxygen free and which contains hydrogen.
24 Citations
12 Claims
-
1. In an overall technique for fabricating an integrated circuit on a wafer having an active device structure, during which fabrication, a patterned layer of photoresist is formed on an overall insulation layer that is itself supported directly on a stop layer that is, in turn, supported directly on the active device structure for using the patterned layer of photoresist in etching holes through the insulation layer to reach an electrical contact that is defined by the active device structure where each electrical contact of a plurality of the electrical contacts is covered by said stop layer and at least some of said electrical contacts include a silicide material and where a plurality of said holes are etched through said overall insulation layer such that one hole is associated with each electrical contact to at least partially expose the stop layer above each electrical contact and where etching of said holes, at least potentially, produces etch related residues, a method comprising:
-
stripping said patterned layer of photoresist and said related residues by etching using a first plasma that contains oxygen without substantially removing said stop layer such that the stop layer serves to protect the silicide material from the oxygen; and after said stripping, etching to remove said stop layer from said contacts using a second plasma that is oxygen free, at least to an approximation, and which second plasma contains hydrogen gas. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
-
Specification