×

Sub-quarter-micron copper interconnections with improved electromigration resistance and reduced defect sensitivity

  • US 6,069,068 A
  • Filed: 10/08/1997
  • Issued: 05/30/2000
  • Est. Priority Date: 05/30/1997
  • Status: Expired due to Fees
First Claim
Patent Images

1. A method for forming multilevel interconnections of copper lines isolated from one another by dielectric insulation for making contacts to electrical features in a substrate, the method comprising the steps of:

  • (a) preparing a substrate having a dielectric insulation layer to receive copper lines in a defined pattern;

    (b) optionally depositing a metallic liner in said pattern;

    (c) depositing in said pattern a layer of an element capable of forming an intermetallic compound with copper wherein said element is selected from the group consisting of lanthanum and tin;

    (d) subsequently depositing in said pattern a physical vapor deposition layer of copper having a thickness of less than about 800 angstroms;

    (e) depositing over the physical vapor deposition copper layer by a different process a layer of copper to substantially fill said pattern; and

    (f) heating the substrate to react the intermetallic forming element with said layer of copper which substantially fills said pattern to form a layer of intermetallic compound.

View all claims
  • 3 Assignments
Timeline View
Assignment View
    ×
    ×