Patent · US Expired

Sputtering method for producing solder-fast copper layers

US3930975A · kind A · utility

7Cited by

4References

15Claims

0Family size

Assignee

Robert Bosch GmbH · DE

Inventors

Gert Siegle · Berlin, DE
Hans Lutz
Helmut Adam
Erhard Gossl · Gerlingen, DE

Key dates

Filing date	Oct 10, 1974
Grant date	Jan 6, 1976
Priority date	—
Expiry date	Oct 10, 1994

Classification

Technology area (CPC H)Electricity
CPC primaryH05K3/16
WIPO fieldAudio-visual technology
WIPO sectorElectrical engineering

Abstract

Copper is sputtered onto a substrate to make a solder-fast contact layer by carrying out the sputtering in a discharge of a monatomic gas containing 0.5 to 16% of air, nitrogen or oxygen which reduces the conductivity of the copper layer, but makes it resistant to alloying with a solution in solder, to an extent comparable with the results obtained by the provision of intermediate diffusion barrier layers. Best results are obtained in an argon discharge in the presence of an admixture of nitrogen or air between 2 and 4% by volume. The solder-wetting properties are not impaired.

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