Patent · US Expired

Copper metallization of USLI by electroless process

US6180523A · kind A · utility

271Cited by
11References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 13, 1998
Grant dateJan 30, 2001
Priority date
Expiry dateOct 13, 2018

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01L2924/0002
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

The invention provides three embodiments for forming Cu/Au contacts and interconnects using electroless deposition. The three embodiments have different adhesion and barrier layers for the electroless Cu or Au plugs. The invention discloses a technique of utilizing electroless deposition in USLI circuits. This metalization process is an additive and selective to provide conducting layers as well as an interconnection between layers of a multilevel conductive metal semiconductor device. The first embodiment uses adhesion layers formed of Ni, Al, polysilicon or PdSi.sub.x ; and a barrier layer composed of Ni--B, Ni, Pd, or Co and has first and second metal plugs formed by selective Cu or Au electroless processes. The second embodiment forms adhesion layers of PdSi.sub.x. The third embodiment forms adhesion layers of activated Ti or Al. Cu or Au plugs are selectively electroless deposited to form interconnects.

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