Life cycle assessment of Japanese high-temperature conductive adhesives.
The electrically conductive adhesives (ECA) are on the verge of a breakthrough as reliable interconnection materials for electronic components. As the ban of lead (Pb) in the electronics industry becomes a reality, the ECA's could be attractive overall alternatives to high melting point (HMP) Pb-based solder pastes. Environmental life cycle assessment (LCA) was used to estimate trade-offs between the energy use and the potential toxicity of two future types of ECA's and one HMP Pb-based. The probability is around 90% that the overall CO2 emissions from an ECA based on a tin-bismuth alloy are lower than for a silver-epoxy based ECA, whereas the probability is about 80% that the cumulative energy demand would be lower. It is more uncertain whether the tin-bismuth ECA would contribute to less CO2, or consume less energy, than a HMP Pb-based solder paste. Moreover, for the impact categories contributing to the life-cycle impact assessment method based on end point modeling (LIME) damage category of human health, the tin-bismuth ECA shows a 25 times lower score, and a silver-epoxy based ECA shows an 11 times lower score than the HMP Pb-based solder paste. In order to save resources and decrease CO2 emissions it is recommended to increase the collection and recycling of printed board assemblies using silver-epoxy based ECA.
Andrae
Anders S G
AS
Research Center for Life Cycle Assessment, National Institute of Advanced Industrial Science and Technology (AIST), 16-1 Onogawa, Tsukuba, Ibaraki 305-8569, Japan. a.andrae@aist.go.jp
Itsubo
Norihiro
N
Yamaguchi
Hiroshi
H
Inaba
Atsushi
A
D000269:Adhesives / Q000633:toxicity; D001729:Bismuth / Q000633:toxicity; D004581:Electronics; D004777:Environment; D006358:Hot Temperature; D006801:Humans; D007564:Japan; D018570:Risk Assessment; D012834:Silver / Q000633:toxicity; D014001:Tin / Q000633:toxicity
D000269:Adhesives; D012834:Silver; D014001:Tin; D001729:Bismuth