Accession Number:

ADA276228

Title:

Reliability of Multilayer Copper/Polyimide

Descriptive Note:

Final technical rept.

Corporate Author:

CLARKSON UNIV POTSDAM NY

Report Date:

1993-11-01

Pagination or Media Count:

25.0

Abstract:

The reliability of copperpolyimide PI multilayer structures was analyzed and found to depend on processing and environmental conditions. Copper films were deposited by thermal evaporation and patterned by contact lithography. Preimidized P12590-D polyimide films were spin coated over the copper with upper layers deposited as required. While the electrical characteristics of the multilayer structures generally behaved as expected, the softening of the underlying PI films led to observation of film buckling and dielectric breakdown in some samples. Consequently, alternate low temperature plasma and laser techniques for depositing copper on PI films, instead of PI films on copper, were explored to improve the reliability of the resulting CuPI multilayer structures. Copper films were deposited on PI substrates by radio frequency 13.56 MHz plasma-induced reduction and excimer laser-induced ablation of copper formate. While the CuPI interface appears clean, the reduction of the formate was not complete with some residual carbon contamination in the copper film. Several methods for improving the purity of the Cu films were investigated. Diamondlike carbon DLC films are excellent barriers for the diffusion of Cu in CuSi structures. DLC films, due to their excellent compatibility with PI, may play a similar useful role in CuPI structures and improve their reliability. CopperpolyimidePI, Diamondlike carbonDLC films, CuPI Multilayer structures.

Subject Categories:

  • Inorganic Chemistry
  • Physical Chemistry
  • Polymer Chemistry
  • Coatings, Colorants and Finishes

Distribution Statement:

APPROVED FOR PUBLIC RELEASE