Volume 4 Issue 2/3 ( September 2017 )

Pages 12-17

A Multi-Layer Stacked All Sol-Gel Fabrication Technique for Vertical Coupled Waveguide

Ahmad Syahrin Idris, Sampad Ghosh, Haisong Jiang, Kiichi Hamamoto


A multi-layer vertically stacked all sol-gel fabrication technique on bulk silicon is proposed to realize vertical coupling from planar waveguides to 3-dimensional structures. The all sol-gel fabrication technique realizes the capability to stack ZnO sol-gel core layer and SiO2 sol-gel cladding and core separation layers. A major issue with sol-gel based fabrication is the appearance of cracks on the sol-gel layer, and these were improved by a slow cooling process of 1°C/min after 500°temperature annealing in addition to a SiO2 surface cleaning using photoresist remover. As a result, a multi-layer vertically stacked structure with a ZnO core layer thickness of 300 nm and SiO2 cladding/core separation layer thickness of 1.5 μm was successfully fabricated on bulk Si.

Keywords: vertical stacking, photonics, sol-gel.