remarkable family of hybrid inorganic-organic materials shows outstanding
promise as the basis for volume manufacture of sophisticated electronic
and electro/optical devices, using low cost materials and production techniques.
The DONDODEM project is bringing the technology much closer to commercial
realisation - offering Europe a significant advantage in key markets such
as telecommunications, information processing and multimedia. These polymers
and production technologies could offer consumers affordable optical 'fibre
to the home' solutions, for example for very high speed internet and telecommunications
connections and applications.
(inorganic-organic polymers, a registered trademark of Fraunhofer-Gesellschaft
resulted originally from a Brite-Euram II project on the 'development
of new dielectrical and optical materials, testing and comparison with
existing polymers and application in multi-chip-modules'. The follow-up
project under Brite-Euram
3 involved an enlarged consortium of research institutes and companies
involved in the electronics and optical sectors.
ORMOCER®s exhibit a unique blend of dielectric and optical transmission
properties, combined with environment-friendly low-temperature processability
and the thermal stability to withstand subsequent metallisation and soldering.
This makes them ideal for the mass production of multi-chip modules (MCMs)
for a wide variety of consumer and professional equipment.
structure of an ORMOCER® comprises a silicon-oxygen network modified
by the introduction of chemically cross-linkable organic components. Variation
of the inorganic-organic precursors enables the properties of the end
product to be tuned precisely to application requirements.
of the resin in organic solvents gives a range of low- to high-viscosity
lacquers that are easily applied as thin layers onto inexpensive polymeric
printed circuit board (PCB) substrates, by industry-standard procedures.
After final curing at temperatures as low as 120° to 170°C, they
withstand subsequent processes such as wave-soldering at up to 280°C.
uncured lacquers act as negative photoresists, enabling patterning
and development of thin films using conventional photolithographic
build-up processing can produce multi-layer substrates or packages
with high density circuit patterns that can contain both electrical
and optical interconnects and also passivation layers. The free-flowing
ORMOCER®s also give better than 95% planarisation (very flat
layer surfaces) that facilitate multi-layering and flip-chip mounting.
By contrast, competitive materials currently under development require
curing temperatures of 250° to 350°C, ruling out the cheaper
substrates - while planarisation is much poorer.
optical waveguides, employed to direct light signals from emitting
sources to receiving detectors or fibre-optic cables, two ORMOCER®
grades with differing refractive indices are required. One forms
the lightguiding core, while the other surrounding layers serve
as reflective cladding. However, electrical interconnects can also
be formed by metallisation on the same layers - so complete structures
can be produced within just two grades and three layers. This simplification
enables novel efficient systems solutions and also has strong environmental
advantages, mainly due to much higher performance-size ratio but
also in terms of reducing process energy consumption and solvent
the end of the Brite-Euram II project in 1998, the consortium was
already able to demonstrate the world's smallest PentiumTM MCM-L/D
and to show an ability to integrate for the first time truly electrical
and optical interconnects in the same substrate.
initial successes attracted major international attention, and encouraged
more European partners to join DONDODEM, forming an alliance of
leading researchers and industrial players from the electronics
and optical sectors. Even such commercially competitive organisations
felt able to join this co-operative research initiative, pooling
their separate expertise to the ultimate benefit of all participants.
the three-year project, which runs until September 2001, the emphasis
has moved from materials development and characterisation to the
investigation of scalable processes that could put ORMOCER®s
onto world markets by 2001.
In Germany, according to the Fraunhofer Institute for Silicate Research
is gearing up to produce larger batches of the lacquers to permit
more extensive pilot trials. At the same time, Swedish partner Viasystems
is working on a curtain coating process that will enable substrates
to be covered at rates of up to 5 m/s.
major innovation is the introduction of combined lithographic/reprographic
patterning by Germany's Institute for Applied Optics and Precision
University and Süss
MicroTec. Sweden's ACREO,
which recently acquired a state-of-the-art high-resolution mask-aligning
system handling up to 25 0.6 x 0.6 m2 panels per hour. A demonstrator
module produced by the Swiss Center for Electronics and Microtechnology
(CSEM) that bundles
four laser emitters, four lenses, diffraction devices and overall
protection is another example that illustrates the versatility of
the new ORMOCER® materials.
and the Technical
University of Berlin have preliminarily proved the efficiency
of wire-bonding and flip-chip component application, and Berlin
University is now conducting long-term reliability testing.
the same time, Bosch and Thomson-CSF Detexis are investigating the
feasibility of thick-layer coating - up to 150 µm - and patterning
which will pave the way for high frequency MCMs and yet more specialised
optical and electro-optical applications.
base for future markets
to DONDODEM co-ordinator Dr Michael Popall of the ISC, the patented
ORMOCER® technology gives Europe one very essential basis to
compete in tomorrow's performance and price-driven markets. It will
help to reinforce the EU's strong position in mobile communication,
while low-cost electro-optical components will hasten the realisation
of a future-proof broadband fibre-to-the-home infrastructure. More
opportunities will be created for large and small enterprises in
applications ranging from laser pointers and readers to high-speed
data exchange networks.
research in the New materials & production
technologies generic action is set to reduce major differences
in the cost of integrating electronic and optical components.
- Development of new dielectric and optical materials and process-technologies
for low cost electrical and/or optical packaging and testing of
precompetitive demonstrators (BRPR980638)