Naoki Kitamura

Photosensitivity in silica-based waveguides deposited by atmospheric pressure chemical vapor deposition.

By using a Mach-Zehnder interferometer, we evaluated photosensitivity in silica-based waveguides deposited by atmospheric pressure vapor deposition. Our results show that photosensitivity with ArF excimer laser irradiation was ten times greater than photosensitivity with KrF excimer laser irradiation. ArF excimer laser irradiation induced a refractive-index change of greater than 2 x 10(-3) at 1.55 mum and a birefringence between TE and TM modes of less than 6 x 10(-5). It has also been determined that the photoinduced absorption change of 90 dB/mm at 210 nm cannot account for a refractive-index change greater than 10(-3).

Silica-based planar optical waveguide devices by TEOS/O/sub 3/ APCVD method

We demonstrate that, with our tetraethoxysilane (TEOS)/O/sub 3/ atmospheric pressure (AP) CVD method, metal materials for etching masks and electrical wiring can be formed directly on Si before silica film deposition, which makes this method extremely attractive for highly functional hybrid-integrated optical modules. Hybrid-integrated optical transceivers and SOA gate matrix switches have been demonstrated with this method.