Athermal silica-based interferometer-type planar light-wave circuits realized by a multicore fabrication method

Abstract

Athermal silica-based interferometer-type planar light-wave circuits were realized by a newly developed multicore fabrication method. In this method, inductively coupled chemical-vapor deposition and polishing technologies are adopted on a silica substrate with a trench-type waveguide pattern prepared by reactive ion etching. Two kinds of deposited core material, 10GeO2-90SiO2 (mol. %) and 8GeO2-5B2O3-87SiO2 (mol. %), which show wavelength temperature dependence of 9.7 and 8.1 pm/degree C, respectively, were used to prepare the waveguide sections in a device. By adjustment of the lengths of waveguide sections with these two different core materials, athermal characteristics of less than 0.5 pm/degree C were achieved for Mach-Zehnder interferometer filter devices at the 1.55-microm wavelength range while the temperature varied from -20 to 80 degrees C. The new method is also applicable for the preparation of many other kinds of functional devices.

Photosensitivity of 20GeO2 : 80SiO2hydrogen-loaded and non-hydrogen-loaded thin films

“…One can also take advantage of photosensitivity to simplify the fabrication of planar light wave circuits (PLC) by directly writing/imprinting a buried channel waveguide in photosensitive films without the use of photolithography and etching technique. For such a purpose, a large refractive index change is desired [5]. The majority 1 Author to whom any correspondence should be addressed.…”

Photosensitivity of sol–gel derived inorganicxB2O3 : 20GeO2 : (80 −x)SiO2system with various boron concentrations

“…Fabrication of planar lightwave circuit (PLC) devices based on silica-on-silicon technology is generally realized by the conventional technique which involves a multi-step process and complex methods like photolithography and etching [1][2][3]. Alternatively, the device fabrication by direct ultra-violet (UV) writing in photosensitive films is attractive for developing PLC due to its simplicity.…”

Development of highly photosensitive low loss inorganic sol-gel films for direct ultraviolet-imprinting of planar waveguides

“…Depending on the amount of water and catalyst[204][205][206][207][208][209][210][211][212], hydrolysis may go to completion. The major variables in the reaction sequence include the type of precursor, the catalyst (acid or base) and its concentration (pH level), the ratio [H 2 O]/[Si], and the reaction temperature.…”