This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
Development of Lead-Free Soldering Technology and Its Application
Technical Paper
2000-01-C043
Sector:
Language:
English
Abstract
In recent years, the solder used to mount electronic components
onto printed circuit boards has become a social issue because of
the lead it contains. To resolve the problem, the development of a
lead-free solder and bonding technology that utilizes it are not
only research themes of industry but national research programs as
well.
In light of the circumstances, we developed an Sn-Ag solder with
minute quantities of Bi and other additives, and applied it for the
first time in the industry to a printed circuit board for portable
MD player. The developed solder has proven workable under current
production temperature conditions (profile that peaks at 230
degrees centigrade) and reliable for bonding electronic component
leads in mass-production. Other studies are currently underway into
identifying the bonding mechanism and reliability evaluation
methods and standards, and to establish reflow processing
technology for large boards, which are characterized by wide
temperature variation, for eventual use with factory automation
controllers and other products. One reflow process using a Sn-Cu
solder has been brought to practical application with VCRs. Use
will eventually be expanded to other products in the future.