1996 Electronics Industry Environmental Roadmap - Civil and ...

Appendix A
IPC Substrate thickness in emerging modules will drop below 125 µm and
approach 25 µm. New equipment will have to be developed to deal
with these very thin materials. The cost of creating smaller vias and
conductors will also have to be addressed. Methods of inexpensively
creating large volumes of small vias such as plasma, laser ablation,
chemical etching, or gang punching, will have to be developed.
Imaging technology will need to address laser patterning and direct
imaging systems to increase resist resolution. Also, additive
technology with higher precision and consistency will be required.
Also, additive metal deposition technology, which requires higher
precision, consistency and resolution will have to be used for
manufacture of fine conductors and miniaturized vias.
The substrate dielectric materials for the modules, will have to include
laser ablatable or photoimagible unsupported homogenous films,
materials with lower dielectric constant, higher Tg, lower moisture
absorption, and better dimensional stability.
Materials trends: review page B-31 and B-32 of the IPC map.
Conventional Assembly
Surface mount continues at the expense of through hole with surface
mount reaching 70-80%, 20-25% through-hole with