Performances of porous silicon optical waveguides

To verify the availability of a porous silicon (PS) technology for applications to photonic devices, fundamental chracteristics of PS waveguides are investigated. An edge-emitting device with an optical waveguide is fabricated by current modulation technique during anodization. The net internal loss for prepared samples is measured by varying the length of excitation beam. The experimental results show that the internal loss increases with decreasing the operation wavelength, possibly due to self-absorption and Rayleigh scattering. Besides the step-index PS waveguides, buried-type waveguides can be fabricated based on a doping modulation technique. A theoretical analysis about a bending loss is also carried out. The results of experimental and theoretical analyses suggest that a curveture radius capable of guiding Lightwave can be significantly minimized, owing to a difinitely different refractive indedices between the core and cladding region.