Method for forming metal wirings of semiconductor device

Claim 1

A method of wiring a semiconductor device, comprising the steps of: (1) forming a first insulating layer on a semiconductor substrate; (2) forming contact holes in said first insulating layer; (3) forming a first smooth metal layer on the entire surface of said first insulating layer, the first smooth metal layer completely filling said contact holes; (4) forming a first group of metal wires by applying a photolithographic process to said first smooth metal layer, each wire of the first group being arranged at regular intervals; (5) forming sidewall insulating spacers on side surfaces of each wire of said first group of metal wires and etching said first insulating layer between said sidewall spacers to an even depth; (6) forming a second smooth metal layer on the entire surface of the structure which results from step (5), the second smooth metal layer completely filling spaces between said sidewall spacers; and (7) forming a second group of metal wires on said spaces between said sidewall spacers by anisotropically etching said smooth second metal layer, the second group of metal wires being insulated from said first group of metal wires by said sidewall spacers.

Claim 2

A method of wiring a semiconductor device, comprising the steps of: (1) forming a first insulating layer on a semiconductor substrate; (2) forming contact holes in said first insulating layer; (3) forming a first smooth metal layer on the entire surface of said first insulating layer, the first smooth metal layer completely filling said contact holes; (4) forming a first group of metal wires by applying a photolithographic process to said first smooth metal layer, each wire of the first group being arranged at regular intervals; (5) forming sidewall insulating spacers on side surfaces of each wire of said first group of metal wires and etching said first insulating layer between said sidewall spacers to an even depth; (6) forming a second smooth metal layer on the entire surface of the structure which results from step (5), the second smooth metal layer completely filling spaces between said sidewall spacers; and (7) forming a second group of metal wires on said spaces between said sidewall spacers by anisotropically etching said smooth second metal layer, the second group of metal wires being insulated from said first group of metal wires by said sidewall spacers.

Claim 15

A method for forming wires on a semiconductor device, comprising the steps of: forming a first group of metal wires, each wire arranged at a given interval from wires which are adjacent to said each wire; forming sidewall spacers comprising an insulating material on side surfaces of each wire of said first group of metal wires using an etchback method; and forming a second group of metal wires, each wire of the second group being placed in a spacing between two adjacent metal wires of said first group using an etchback method, the second group of metal wires being aligned to said first group of metal wires, each wire of the second group being separated form each wire of the first group by said sidewall spacers.

Claim 16

A method for forming wires on a semiconductor device, comprising the steps of: forming a first group of metal wires, each wire arranged at a given interval from wires which are adjacent to said each wire; forming sidewall spacers comprising an insulating material on side surfaces of each wire of said first group of metal wires using an etchback method; and forming a second group of metal wires, each wire of the second group being placed in a spacing between two adjacent metal wires of said first group using an etchback method, the second group of metal wires being aligned to said first group of metal wires, each wire of the second group being separated form each wire of the first group by said sidewall spacers.