he 9th Pan Pacific Microelectronics Symposium Exhibits & Conference, Kahuku, Oahu, Hawaii, Feb. 2004
Naval Surface Warfare Center, Carderock Division
West Bethesda, MD, USA
Michael Pecht and Craig Hillman
University of Maryland
College Park, MD 20742
As the current trends toward miniaturization take hold, proper cleanliness levels become more difficult to achieve. In addition, effective cleaning requirements may not be in place. The smaller spacing between conductors also yields a larger electric field, which in conjunction with insufficient cleaning can lead to dendritic growth. This paper investigates the effects of chloride contamination and electric field on the migration behavior of hot air solder level (HASL) plated FR-4 printed circuit boards. It was found that chloride contamination level and electric field influence which failure mechanism is occurring, electrochemical migration or electrolytic corrosion. This study concludes that current industry specifications for cleanliness may be inadequate for the next generation of electronic assemblies.
Key words: electrochemical migration, dendritic growth, electric field, contamination
Complete article is available to CALCE Consortium Members.