System and method for removal of photoresist and residues following contact etch with a stop layer present
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 use in etching contact openings to reach a contact arrangement that is defined by the active device structure in which each contact of a plurality of contacts is covered by said stop layer, a method, comprising:
- selectively etching, using a first plasma in cooperation with the patterned layer of photoresist, to form a plurality of contact openings through said overall insulation layer such that one contact opening is associated with each contact in a way which at least partially exposes the stop layer above each contact and which, at least potentially, produces etch related residues;
stripping said patterned layer of photoresist and said related residues; and
after stripping, removing said stop layer from said contacts.
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Accused Products
Abstract
In processing an integrated circuit structure including a contact arrangement that is initially covered by a stop layer, a first plasma is used to etch to form openings through an overall insulation layer covered by a patterned layer of photoresist such that one contact opening is associated with each contact. Stripping of the patterned layer of photoresist and related residues is performed. After stripping, the stop layer is removed from the contacts. In one feature, the stop layer is removed from the contacts by etching the stop layer using a plasma that is generated from a plasma gas input that includes hydrogen and essentially no oxygen. In another feature, the photoresist is stripped after the stop layer is removed. Stripping the patterned layer of photoresist and the related residues is performed, in this case, using a plasma that is formed predominantly including hydrogen without oxygen.
210 Citations
30 Claims
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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 use in etching contact openings to reach a contact arrangement that is defined by the active device structure in which each contact of a plurality of contacts is covered by said stop layer, a method, comprising:
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selectively etching, using a first plasma in cooperation with the patterned layer of photoresist, to form a plurality of contact openings through said overall insulation layer such that one contact opening is associated with each contact in a way which at least partially exposes the stop layer above each contact and which, at least potentially, produces etch related residues;
stripping said patterned layer of photoresist and said related residues; and
after stripping, removing said stop layer from said contacts. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 17, 25, 26)
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16. 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 silicon nitride stop layer that is, in turn, supported directly on the active device structure for use in etching at least one contact opening to reach a silicide containing contact which is defined by the active device structure and covered by the stop layer, a method, comprising:
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selectively etching, using a first plasma in cooperation with the patterned layer of photoresist, to form a contact opening through said overall insulation layer such that the contact opening is associated with said contact in a way which at least partially exposes the stop layer above the contact and which, at least potentially, produces etch related residues;
stripping said patterned layer of photoresist and said related residues; and
after stripping, removing said stop layer from said contacts using a second plasma that is formed predominantly from hydrogen gas in an absence of oxygen, said second plasma being formed from a plasma gas input that includes (i) hydrogen gas, (ii) a nitrogen containing gas in an amount up to approximately 10% of the plasma gas input, and (iii) a fluorine containing gas up to approximately 5% of the plasma gas input.
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18. In an overall technique for fabricating an integrated circuit on a wafer having an active device structure and as part of an intermediate step a contact, which includes a silicide and which forms part of the active device structure, is protected by a stop layer, a method for removing said stop layer from the contact, said method comprising:
etching said stop layer using a plasma that is generated from a plasma gas input that includes hydrogen and essentially no oxygen to remove the stop layer from said contact. - View Dependent Claims (19, 20, 21, 22, 23)
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24. 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 use in etching at least one contact opening to reach a silicide containing contact which is defined by the active device structure and covered by the stop layer, a method, comprising:
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selectively etching, using a plasma in cooperation with the patterned layer of photoresist, to form a contact opening through said overall insulation layer such that the contact opening is associated with said contact in a way which at least partially exposes the stop layer above the contact and which, at least potentially, produces etch related residues;
removing said stop layer from said contacts using a second plasma that is formed predominantly from hydrogen gas in an absence of oxygen; and
stripping said patterned layer of photoresist and said related residues using a third plasma that is formed predominantly including hydrogen without oxygen. - View Dependent Claims (27, 28, 29, 30)
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Specification