AL2O3 and Y2O3 Thin Films for Active Integrated Optical Waveguide Devices

$Al_{2}O_{3}$ and $Y_{2}O_{3}$ are both very promising host materials for active integrated optics applications such as rare-earth ion doped waveguide lasers. In this paper, a reactive co-sputtering process for stable, target condition-independent deposition of $Al_{2}O_{3}$ layers with high optical quality is discussed. The loss of as-deposited $Al_{2}O_{3}$ waveguides in the near infrared wavelength range was 0.3 dB/cm. Reactive ion etching of both $Al_{3}O_{2}$ and $Y_{2}O_{3}$ thin films for defining channel waveguide structures was investigated and compared using $CF_{4}/O_{2}, BCl_{3}, HBr$ and $CL_{2}$ inductively coupled plasmas