Patent · US Expired

Silver under-layers for electroless cobalt alloys

US7064065B2 · kind B2 · utility

4Cited by
107References
37Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 15, 2004
Grant dateJun 20, 2006
Priority date
Expiry dateOct 15, 2024

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01L21/76874
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

In one embodiment, a method for depositing a capping layer on a substrate surface containing a copper layer is provided which includes exposing the substrate surface to a zinc solution, exposing the substrate surface to a silver solution to form a silver layer thereon and depositing the capping layer on the silver layer by an electroless deposition process. A second silver layer may be formed on the capping layer, if desired. In another embodiment, a composition of a deposition solution useful for forming a cobalt tungsten alloy contains calcium tungstate, a cobalt source at a concentration within a range from about 50 mM to about 500 mM, a complexing agent at a concentration within a range from about 100 mM to about 700 mM, and a buffering agent at a concentration within a range from about 50 mM to about 500 mM.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.