ORMOCER®s (Organic-inorganic hybrid polymers) for telecom applications:: Structure/property correlations

The development and characterization of fluoroaryl functionalized organic-inorganic hybrid polymers for optical waveguide applications is presented. The materials are prepared from organoalkoxysilanes in a two-step process. The first step is the formation of the inorganic polysiloxane network by hydrolysis and polycondensation in order to obtain a soluble resin. This can be mixed with a photo initiator and applied onto a substrate as a photo-sensitive film. Micro patterns (waveguides with core and cladding) are then manufactured in a second step by exposure to UV-light through a mask. The polymers are characterized with respect to application in the fabrication of telecom optical waveguide devices. Thus, special attention is turned to optical losses in the telecom wavelengths at 13 10 nm and 1550 nm as well as to refractive indices. During all stages of ORMOCER (R) preparation, structure-property correlations are deduced from presented characterization data. Various spectroscopic tools give an insight into network structures of polycondensate resins and cured hybrid polymer samples. Si-29-NMR in particular is used for the quantitative analysis of siloxane species. With the aid of molecular modeling, structural characteristics of oligomeric intermediates as determined by experiment are visualized. ORMOCER (R) resins with low optical losses of 0.28 dB/cm at 1310 nm and 0.42 dB/cm at 1550 nm, respectively, are prepared. Subsequent micropatterning by means of photolithography results in waveguide and other test patterns. A low optical loss of 0.51 dB/cm at 1550 nm is measured on a waveguide manufactured from a photopatternable fluoroaryl functionalized ORMOCER (R).