Polymer optical waveguide devices are getting popular for next generation FTTH application. In order to accelerate the development of polymer optical devices, evaluation of waveguide characteristics should be speeded up. Polymer optical chip containing a combination of 45°-angled cut waveguide, Y-splitter and S-bend structures was designed and fabricated for simple evaluation of multimode waveguides. Input launching such as light source, mode scrambler was investigated for reliable measurement.
Laser-induced chemical vapor deposition is applied to fabricate three-dimensional microstructures that have cross-sectional profiles other than simple combination of deposited fibers. To fabricate microstructures other than combined wire-frames, a thin layer of deposit in desired patterns is first written using laser-direct-write technique and on top of this layer a second layer is deposited to provide the third dimension normal to the surface. By depositing many layers, a full three-dimensional microstructure is fabricated. Optimum deposition conditions for direct writing of initial and subsequent layers with good surface quality and profile uniformity are determined. Using an argon ion laser and ethylene as the light source and reaction gas, respectively, fabrication of three-dimensional carbon microstructures with the proposed method is demonstrated.
We have fabricated micro carbon rod/needle structures of size 30 to 400 μm on graphite substrate by the pyrolytic decomposition of ethylene precursor gas using argon ion laser (514.5 nm) at different laser power and chamber pressure. The micro carbon rods were characterized using Raman spectroscopy and two broad peaks centered at 1320-1345 cm-1 and 1589-1602 cm-1 were observed, which corresponds to D (disorder) and G (graphitic) bands, respectively. LCVD grown micro carbon rods consists of highly polycrystalline graphite as well as amorphous carbon phase. The microstructural features of the LCVD grown micro carbon rods are discussed in detail.