1996 Electronics Industry Environmental Roadmap - Civil and ...

IPC
OIDA
SIA/SEMATECH
Interconnect and Assembly
Appendix A
NEMI Solder-based direct chip attach processes and multi-layer PWBs and
ceramic or silicon substrates will likely be used for systems requiring
high reliability, while adhesive-based direct chip attach processes and
thin PWBs or flex circuits will likely be used where cost is the
dominant factor in system design.
A requirement will be new materials for low cost wafer bumping.
Lead-free solder systems will be implemented in the near term but will
be replaced over time as Z-axis adhesive technology is developed
Plastic, “hermetic-like” packaging, will become increasingly important
Ceramic substrate, C4 processes for direct chip attach need to give way
to organic substrates such as BT and others formulated with high
temperature epoxy resins. Further, the cost and complexity of C4
requires alternative solder-based and adhesive-based processes.
Technology requirements are driven mainly by end use.
High thermal conductivity, inorganic materials increasingly used.
Trend to less exotic materials, fewer layers, smaller substrates, less
costly materials.
Attachment structure (solder bumps, conductive adhesives, palladiumcoated
lands) already on substrate.
(continued)
NEMI Big requirement: DFM, DFE, DFA.
In a typical “best-in-class” high volume electronics assembly plant,
board assembly processes will account more than 50% of the
manufacturing and capital equipment, more than 65% of the defect
opportunities, and more than 50% of all the parts in the product, and
more than 50% of all the direct material in the product.
In the near term, most important is the transition from packaged ICs to
package-less direct-chip attach and the associated assembly process.
Most important for low cost is to encourage a much higher level of
technology and information sharing for board assembly processes.
Other key priorities include the creation of a SEMATECH-like
organization, centers of excellence, increased government sponsorship
of programs, support for PCMCIA research, cooperative development
of key technologies such as stereo-lithographic fabrication of plastic
parts to reduce cycle time, DCA, CIM and BGAs.
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