K. Worhoff, J. D. Bradley, F. Ay, and M. Pollnau, "Low-Loss Al2O3 Waveguides for Active Integrated Optics,"
in Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference and Photonic Applications Systems Technologies,
OSA Technical Digest Series (CD)
(Optical Society of America, 2007), paper CMW5.
Reactively co-sputtered amorphous aluminum oxide layers with low loss (0.11 dB/cm at NIR wavelength) have been fabricated. Channel waveguides with steep, smooth side walls have been etched by a dry process.