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In the field of modern information technology, optoelectronics are being widely used, and play an increasingly
important role. Meanwhile, the demand for more flexible circuit carriers is rapidly growing, since flexibility
facilitates the realization of diverse functions and applications. As a potential candidate, transparent polymer
substrates with a thickness of about a hundred micrometers by virtue of their low cost and sufficient flexibility
are getting more attention. Thus, accomplishing an integration of optoelectronic components into polymer based
flexible circuit systems increasingly is becoming an attractive research topic, which is of great significance for
future information transmission and processing. We are committed to developing a new microchip bonding
process to realize it. Taking into account the fact that most economical transparent polymer substrates can
only be processed with restricted thermal loading, we designed a so-called optode instead of a widely adopted
thermode. We employ UV-curing adhesives as bonding materials; accordingly, the optode is equipped with a
UV irradiation source. An investigation of commercial optoelectronic components is conducted, in which their
dimensions and structures are studied. While selecting appropriate transparent polymer substrates, we take
their characteristics such as UV transmission degree, glass transition temperature, etc. as key criterions, and
choose polyethylene terephthalate (PET) and polymethyl methacrylate (PMMA) as carrier materials. Besides
bonding achieved through the use of adhesives cured by the optode, underfill is accordingly employed to enhance
the reliability of the integration. We deposit electrical interconnects onto the polymeric substrate to be able to
bring the optoelectronic components into electrical operation. In order to enlarge the optical coupling zone from
component to substrate within the proximity of the adhesive or underfill, we employ transparent interconnects
made of indium-tin-oxide. We present the results of the performance tests, including the contact resistances,
mechanical tests and environmental tests.
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