Method for forming three-dimensional interconnection, circuit arrangement comprising three-dimensional interconnection, and metal film-forming composition for three-dimensional interconnection
In a method for forming a three-dimensional interconnection, a contact plug is formed within a through hole provided in a substrate and an upper wire formed on an upper side of the substrate and a lower wire formed on a lower side are electrically connected to one another by the contact plug. A coating film is formed on an upper surface of the substrate and inner surface of the through hole by applying a metal film-forming composition containing at least one salt of and a particle of a metal to the substrate provided with the through hole. A metal film is formed by heating the coating film, and plated by filling up the through hole by depositing a conductor on the metal film by a plating process using the metal film as a seed layer. An excess conductor deposited in the plating is removed by a chemical mechanical polishing process.
1. A method for forming a three-dimensional interconnection in which a contact plug is formed within a through hole provided in a substrate or an electrically insulative film and an upper wire formed on an upper side of the substrate or the electrically insulative film and a lower wire formed on a lower side of the substrate or the electrically insulative film are electrically connected to one another by the contact plug, the method comprising:
forming a coating film on an upper surface of the substrate or the electrically insulative film and on an inner surface of the through hole or an inner surface of the blind via hole by applying a metal film-forming composition containing at least one of a salt of and a particle of a metal selected from Group 10 and Group 11 of the Periodic Table to the substrate or the electrically insulative film provided with the through hole or to the substrate or the electrically insulative film provided with the blind via hole becoming the through hole;
forming a metal film by heating the coating film,
plating by filling up the through hole or the blind via hole by depositing a conductor on the metal film by a plating process using the metal film as a seed layer; and
removing, by a chemical mechanical polishing process, an excess conductor deposited in the plating.
2. The method for forming a three-dimensional interconnection according to claim 1 , wherein the metal film-forming composition has a viscosity of 1 Pa·s or less and a metal concentration of 5 to 50% by mass.
3. The method for forming a three-dimensional interconnection according to claim 1 , wherein the coating film is heated to 100 to 200° C. in an atmosphere with an oxygen concentration of 500 ppm or less or vacuum in the forming of the metal film.
4. The method for forming a three-dimensional interconnection according to claim 1 , wherein the metal film formed by heating the coating film has an average value of thickness on the inner wall of the through hole or the inner wall of the blind via hole of 10 to 2000 nm.
5. The method for forming a three-dimensional interconnection according to claim 1 , wherein the metal film is a sintered film of copper particles.
6. The method for forming a three-dimensional interconnection according to claim 1 , wherein the through hole or the blind via hole has an opening diameter of 1 to 100 μm and a depth of 20 to 200 μm and the ratio of the depth to the opening diameter ranges from 1 to 50.
7. The method for forming a three-dimensional interconnection according to claim 1 , further comprising, prior to the forming of the metal film: forming a high melting point film that serves as a base material of a barrier layer on an inner surface of the through hole or the blind via hole.
8. A method for forming a three-dimensional interconnection in which a contact plug is formed within a through hole provided in a substrate or an electrically insulative film and an upper wire formed on an upper side of the substrate or the electrically insulative film and a lower wire formed on a lower side of the substrate or the electrically insulative film are electrically connected to one another by the contact plug, the method comprising:
forming a through hole or a blind via hole in the substrate or the electrically insulative film;
forming a bottom seed layer by depositing a conductor by a vapor phase deposition process on a lower end side of the through hole or on a bottom surface of the blind via hole;
forming a coating film covering an upper surface of the substrate or the electrically insulative layer, an inner wall of the through hole or the blind via hole, and an upper surface of the bottom seed layer by applying a metal film-forming composition containing at least one of a salt of and a particle of a metal selected from Group 10 and Group 11 of the Periodic Table to the substrate or the electrically insulative film provided thereon with the bottom seed layer;
forming a metal film by heating the coating film,
plating by filling up the through hole or the blind via hole by depositing a conductor on the metal film by a plating process using the metal film as a seed layer; and
removing, by a chemical mechanical polishing process, an excess conductor deposited in the plating.
9. The method for forming a three-dimensional interconnection according to claim 8 , wherein the metal film-forming composition has a viscosity of 1 Pa·s or less and a metal concentration of 5 to 50% by mass.
10. The method for forming a three-dimensional interconnection according to claim 8 , wherein the coating film is heated to 100 to 200° C. in an atmosphere with an oxygen concentration of 500 ppm or less or vacuum in the forming of the metal film.
11. The method for forming a three-dimensional interconnection according to claim 8 , wherein the metal film formed by heating the coating film has an average value of thickness on the inner wall of the through hole or the inner wall of the blind via hole of 10 to 2000 nm.
12. The method for forming a three-dimensional interconnection according to claim 8 , wherein the metal film is a sintered film of copper particles.
13. The method for forming a three-dimensional interconnection according to claim 8 , wherein the through hole or the blind via hole has an opening diameter of 1 to 100 μm and a depth of 20 to 200 μm and the ratio of the depth to the opening diameter ranges from 1 to 50.
14. The method for forming a three-dimensional interconnection according to claim 8 , further comprising, prior to the forming of the metal film: forming a high melting point film that serves as a base material of a barrier layer on an inner surface of the through hole or the blind via hole.
15. A circuit arrangement comprising a three-dimensional interconnection formed by the method for forming a three-dimensional interconnection according to claim 1 .
16. A circuit arrangement comprising a three-dimensional interconnection formed by the method for forming a three-dimensional interconnection according to claim 8 .