Metal Deposition from Organic Solutions for Microelectronic Applications.

摘要

A unique method for electrochemically depositing metal films from organic solutions was previously demonstrated. It was shown that by plating with this method, metallic particles and layers could be deposited on metals commonly used in the microelectronics industry. The deposition mechanism involved the dissolution of a less noble substrate metal and the simultaneous deposition of more noble metal particles on the surface of substrate, similar to immersion plating in aqueous solutions. This process was also shown to be capable of producing selectively deposited seed layers only on exposed reactive metal surfaces for subsequent electroless and electrolytic metal depositions. This process was highly selective and was compatible with film depositions onto patterned and unpatterned substrates, including printed circuit boards and silicon wafers. Refinement and optimization of the process have resulted in extending the technology to include the deposition of Cu and Pd seed layers from organic solutions onto TiSiN barrier films using in situ activating agents. Additionally, the process was modified to selectively deposit continuous Au films on Cu laminated FR-4 substrates and sputter-deposited Cu films. In this study, the ability to selectively deposit adherent Au thin films and Cu or Pd seed layers from an organic solution onto patterned and unpatterned substrates is demonstrated. The results from process development and microstructural characterization of the deposits are presented.