Three-dimensional integration of passive and active polymer waveguide devices

This thesis presents the design, fabrication, and experimental results of three dimensionally integrated optics. This vertical and horizontal integration of polymer waveguide structures increases the integration density, reduces interconnection routing difficulties, and expands the functional diversity of adjacent devices. The devices discussed depend on the fabrication of vertical slopes using unconventional photolithography and reactive ion etching techniques. The slopes produced allow fully functional three dimensionally integrated optics that incorporate both passive and active waveguide elements.; Passive structures such as vertical waveguide bends, power splitters, and polarization splitters enable three dimensional routing of the optical power among multiple vertical levels. Single mode vertical waveguide bends are demonstrated with polarization insensitive excess losses of 0.2dB. These waveguide structures incorporated bending angles up to 1.5°. Three dimensional 1 x 4 splitters, possess excess losses of 0.5dB and show the ability to fabricate complex waveguide structures in both the horizontal and vertical directions. These vertical power splitters showed controllable power splitting ratios in the output waveguides by controlling the spin cast film thickness within 0.5muM and the slope angle within 0.5°. The vertical polarization splitters incorporated birefringent polymer materials to create an adiabatic mode splitter. These possessed power extinction ratios of about 15dB for both input polarizations. The passive structures of vertical waveguide bends, power splitters, and polarization splitters enable practical three dimensional integrated optics by providing vertical routing capability of the optical signal analogous to those typically found in conventional two dimensional waveguide interconnects.; Three dimensionally integrated active devices such as low-loss hybrid modulators and vertically integrated modulator designs create fully functional waveguide architectures. The hybrid modulators incorporate active and passive polymer components in regions where modulation or low-loss propagation are required. In the general case, these demonstrate the ability to fabricate polymer structures out of dissimilar materials which optimize different device performances. The vertically integrated modulator designs show the ability to fabricate thermally stable active devices on multiple vertical levels. Combining the low-loss hybrid modulators and the vertically integrated modulator designs with three dimensional passive structures shows the true versatility of polymer device integration.