Electroless copper employing hypophosphite as a reducing agent
US6046107A · kind A · utility
3Cited by
12References
7Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Dec 17, 1998 |
| Grant date | Apr 4, 2000 |
| Priority date | — |
| Expiry date | Dec 17, 2018 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC23C18/40
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
Method and baths for electroless depositing Cu on a semiconductor chip using four preferred Cu electroless baths. All four preferred electroless baths use hypophosphite as a reducing agent. The 4 baths use the following mediators (1) Nickel sulfate, (2) Pd Sulfate (3) Co Sulfate (4) Fe Sulfite, and complexing agents (Na Citrite, Boric Acid, Ammonium Sulfite). The baths can operate at a pH between 8 and 10. The invention forms high purity Cu interconnects having adequate step coverage to form in a hole having an aspect ratio greater than 2.7 to 1.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.