Chemically assisted mechanical cleaning of MRAM structures
AssigneeLam Research Corporation
InventorsKatrina Mikhaylichenko, Michael Ravkin
Life of this patent
Estimating the term…
Abstract
A method for post-etch cleaning of a substrate with MRAM structures and MJT structures and materials is disclosed. The method includes inserting the substrate into a first brush box configured for double-sided mechanical cleaning of the substrate. A non-HF, copper compatible chemistry is introduced into the first brush box for cleaning the active and backside surfaces of the substrate. The substrate is then inserted into a second brush box which is also configured to provide double-sided mechanical cleaning of the active and backside surfaces of the substrate. A burst of chemistry is introduced into the second brush box followed by a DIW rinse. The substrate is then processed through an SRD apparatus for final rinse and dry.
Claims15
A method for post-etch cleaning of a substrate having magnetic random access memory (MRAM) structures defined therein, the method comprising:
- providing a substrate having MRAM structures being fabricated thereon, the MRAM structures including copper wiring end multiple-tunnel junction (MTJ) structures and materials;
- inserting the substrate into a first brush box, the first brush box being configured to provide double-sided mechanical cleaning of an active and a backside surface of the substrate;
- applying a first brush against the active surface of the substrate and applying a second brush against the backside surface of the substrate, the first brush and the second brush being PVA brushes having nodules and being applied at a pressure to achieve brush compression between approximately 1–5 mm;
- introducing a copper compatible chemistry into the first brush box for cleaning the active and backside surfaces of the substrate;
- inserting the substrate into a second brush box, the second brush box being configured to provide double-sided mechanical cleaning of the active and backside surfaces of the substrate;
- applying a first brush of the second brush box against the active surface of the substrate and applying a second brush of the second brush box against the backside surface of the substrate, the first brush of the second brush box and the second brush of the second brush box being PVA brushes having nodules, and being applied at a pressure to achieve a brush compression between approximately 1 and 5 mm;
- introducing a burst of chemistry into the second brush box;
- and introducing a deionized water (DIW) rinse into the second brush box, wherein the copper compatible chemistry is ammonia based buffered solution containing chelating agent.
A method for chemically assisted mechanical cleaning of magnetic random access memory (MRAM) structures, the method comprising:
- providing a substrate having MRAM structures being fabricated thereon, the MRAM structures including copper wiring and multiple-tunnel junction (MTJ) structures and materials, and the substrate having an active surface and a backside surface;
- inserting the substrate into a first brush box having a pair of brushes to provide double-sided mechanical cleaning of the active and backside surfaces of the substrate;
- introducing a copper compatible chemistry into the first brush box for cleaning the active and backside surfaces of the substrate the copper compatible chemistry is ammonia based buffered solution containing chelating agent;
- inserting the substrate into a second brush box having a pair of brushes to provide double-sided mechanical cleaning of the active and backside surfaces of the substrate;
- and
- introducing a deionized water (DIW) rinse into the second brush box,
- wherein each of the pair of brushes in the first brush box and in the second brush box is a PVA brush having nodules, and each of the pair of brushes being applied against the active and the backside surfaces of the substrate at a pressure to achieve a brush compression of between approximately 1 and 5 mm.
A method for post-etch cleaning of a substrate having magnetic random access memory (MRAM) structures defined therein, the method comprising:
- providing a substrate having MRAM structures being fabricated thereon, the MRAM structures including copper wiring and multiple-tunnel junction (MTJ) structures and materials;
- inserting the substrate into a brush box, the brush box being configured to provide double-sided mechanical cleaning of an active and a backside surface of the substrate;
- applying a first brush against the active surface of the substrate and applying a second brush against the backside surface of the substrate, the first brush and the second brush being PVA brushes having nodules and being applied at a pressure to achieve brush compression between approximately 1–5 mm;
- introducing a copper compatible chemistry into the first brush box for cleaning the active and backside surfaces of the substrate;
- and
- inserting the substrate into a drying apparatus for final rinse and dry of the substrate, wherein the copper compatible chemistry is ammonia based buffered solution containing chelating agent.
Dependencies are inferred from the claim text.