An optical switch structure based on total internal reflection effects in intersecting silicon oxynitride waveguides has been designed and successfully fabricated. The optical reflection losses of the waveguides have been analyzed and compared with experimental results. It was shown that, apart from materials and scattering losses, the major factors contributing to the reflection losses are waveguide width, reflection facet displacement, and reflection facet tilt angle, with the last factor being the most critical in deciding the overall loss of the device.