skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Growth structures of electroless copper films for printed wiring boards

Journal Article · · Journal of Vacuum Science and Technology. B, Microelectronics Processing and Phenomena; (United States)
OSTI ID:5287743
;  [1]; ;  [2]
  1. Digital Equipment Corp., Greenville, SC (United States)
  2. Univ. of Minnesota, Minneapolis (United States)

Through a mature process, electroless copper deposition occupies an important economic and technological position in the electronics industry today. Virtually all multilayer circuit boards require the process for through hole connections enabling the miniaturization of the board to keep apace with the total electronics trend to higher densities and smaller components. This trend places more stringent requirements on adhesion of the copper and reliability of the film. The process itself consists of two deposition stages, a surface catalyzation with a palladium colloid followed by deposition of copper. The surface presents a composite substrate of greatly different materials on which adhesion is required: copper silicate glass, and polymeric resins of diverse compositions. To facilitate study of the surface structures, the authors have used highly oriented pyrolitic graphite as a substrate. This paper describes how scanning tunneling microscopy (STM) shows the incipient stages of the palladium catalyst and electroless copper. The results of STM investigations have revealed the nucleation, the microisland formation and the surface growth morphology. The surface composition at each step is identified by scanning tunneling spectroscopy. The surface structures and the defect formation on printed circuit board materials are also investigated by AFM.

OSTI ID:
5287743
Journal Information:
Journal of Vacuum Science and Technology. B, Microelectronics Processing and Phenomena; (United States), Vol. 9:2; ISSN 0734-211X
Country of Publication:
United States
Language:
English