Acid blend for removing etch residue
AssigneeMicron Technology, Inc.
InventorsKevin J. Torek, Donald L. Yates
Life of this patent
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Abstract
A method for removing organometallic and organosilicate residues remaining after a dry etch process from semiconductor substrates. The substrate is exposed to a conditioning solution of a fluorine source, a non-aqueous solvent, a complementary acid, and a surface passivation agent. The fluorine source is typically hydrofluoric acid. The non-aqueous solvent is typically a polyhydric alcohol such as propylene glycol. The complementary acid is typically either phosphoric acid or hydrochloric acid. The surface passivation agent is typically a carboxylic acid such as citric acid. Exposing the substrate to the conditioning solution removes the remaining dry etch residues while minimizing removal of material from desired substrate features.
Claims103
A method for processing a semiconductor substrate, the method comprising:
- performing a dry etch process on said semiconductor substrate;
- and
- removing dry etch residues from said semiconductor substrate by exposing said semiconductor substrate to a conditioning solution, wherein the conditioning solution comprises:
- a fluorine source,
- a complementary acid,
- a non-aqueous solvent selected from the group consisting of tetrahydrofuran, propylene carbonate, and blends thereof, and
- a surface passivation agent comprising ethylene diamine tetraacetic acid or ascorbic acid;
- wherein said conditioning solution is substantially free of water, and said fluorine source, said complementary acid, said non-aqueous solvent and said passivation agent are present in said conditioning solution in concentrations suitable for the selective removal of said residues relative to any exposed metal on said semiconductor substrate.
The method of claim herein the HF, non-aqueous solvent, HCl, and surface passivation agent are present in the conditioning solution in the approximate proportion of 0.25-0.3:93-98:0.005-0.009:0.09-0.5.
A method for processing a wafer, the method comprising:
- performing a dry etch process on said wafer;
- and
- removing at least one of organometallic and organosilicate residues of said dry etch process from exposed surfaces of said wafer by treating the wafer with a conditioning solution comprising:
- a fluorine-containing organosilicate-removing agent,
- a non-aqueous solvent selected from the group consisting of tetrahydrofuran, propylene carbonate, and blends thereof,
- an organometallic-removing complementary acid, and
- a surface passivation agent comprising ethylene diamine tetraacetic acid or ascorbic acid;
- wherein said conditioning solution is substantially free of water, and said organosilicate-removing agent, said organometallic-removing complementary acid, said non-aqueous solvent and said passivation agent are present in said conditioning solution in concentrations suitable for the selective removal of said residues relative to any exposed metal on said semiconductor substrate.
The method of claim is 72, wherein said act of removing comprises treating said wafer at a temperature of approximately 38 degrees Celsius.
A method for processing a substrate with patterned photoresist on the substrate surface comprising the steps of:
- providing a substrate with patterned photoresist on a surface of the substrate;
- performing a dry etch process on the substrate, wherein said dry etch process leaves at least one of organometallic and organosilicate residues on said substrate;
- removing any remaining photoresist from the surface of the substrate;
- and
- removing the dry etch residues from the substrate by exposing the substrate to a conditioning solution, said conditioning-solution being a substantially water-free composition suitable for the selective removal of said residues relative to any exposed metal on said semiconductor substrate and comprising:
- a fluorine-containing organosilicate-removing agent, said fluorine-containing organosilicate-removing agent-contributing to the selective removal by said conditioning solution by substantially remaining in molecular form;
- a non-aqueous solvent selected from the group consisting of tetrahydrofuran, propylene carbonate, and blends thereof;
- an organometallic-removing complementary acid present in sufficient amount to contribute to said fluorine-containing organosilicate-removing agent substantially remaining in molecular form;
- and
- a surface passivation agent comprising ethylene diamine tetraacetic acid or ascorbic acid, said surface passivation agent contributing to the selective removal by said conditioning solution by passivating said any exposed metal on said semiconductor substrate.
A method for treating a semiconductor substrate, the method comprising:
- performing a dry etch process on said semiconductor substrate;
- and
- removing at least one of organometallic and organosilicate residues of said dry etch process remaining on exposed surfaces of the substrate while minimizing the removal of metal lines from said exposed surfaces by exposing the substrate to a substantially non-aqueous conditioning solution comprising HF, at least one of tetrahydrofuran or propylene carbonate, HCl, and at least one of ethylene diamine tetraacetic acid or ascorbic acid as a passivation agent in the approximate respective percentage-by-weight ratio 0.01-5.0:80-95:0.003-1.0:0.001-1.0.
A method for treating a semiconductor substrate, the method comprising:
- performing a dry etch process on said semiconductor substrate;
- and
- removing at least one of organometallic and organosilicate residues of said dry etch process remaining on exposed surfaces of the substrate while minimizing the removal of metal lines from said exposed surfaces by exposing the substrate to a substantially non-aqueous conditioning solution comprising HF, at least one of tetrahydrofuran or propylene carbonate, H3PO4, and at least one. of ethylene diamine tetraacetic acid or ascorbic acid as a passivation agent in the approximate respective percentage-by-weight ratio 0.01-5.0:80-90:1-15:0.001-1.0.
A method for treating a semiconductor substrate, the method comprising:
- performing a dry etch process on said semiconductor substrate;
- removing at least one of organometallic and organosilicate residues of said dry etch process remaining on exposed surfaces of the substrate while minimizing the removal of metal lines from said exposed surfaces by exposing the substrate to a substantially non-aqueous conditioning solution comprising HF, at least one of tetrahydrofuran or propylene carbonate, HCl, and at least one of ethylene diamine tetraacetic acid or ascorbic acid as a passivation agent in the approximate respective percentage-by-weight ratio 0.25-0.3:90-98:0.0050-0.009:0.009-0.5;
- and
- rinsing the substrate.
A method for treating a semiconductor substrate, the method comprising:
- performing a dry etch process on said semiconductor substrate;
- removing at least one of organometallic and organosilicate residues of said dry etch process remaining on exposed surfaces of the substrate while minimizing the removal of metal lines from said exposed surfaces by exposing the substrate to a substantially non-aqueous conditioning solution comprising HF, at least one of tetrahydrofuran or propylene carbonate, H3PO4, and at least one of ethylene diamine tetraacetic acid or ascorbic acid as a passivation agent in the approximate respective percentage-by-weight ratio 0.25-0.3:90-94:6-7:0.009-0.5;
- and
- rinsing the substrate.
Dependencies are inferred from the claim text.