Title :
Sharp vertices in asymmetric Y-junctions by double masking
Author :
van der Tol, J.J.G.M. ; Pedersen, J.W. ; Metaal, E.G. ; Oei, Y.S. ; Green, F.H. ; Demeester, P.
Author_Institution :
PTT Res., R. PTT Nederland N.V., Leidschendam, Netherlands
Abstract :
A novel fabrication procedure is presented for the realization of sharp vertices in Y-junctions on InGaAsP/InP. Overlapping masking layers of silica and resist respectively define the two branches in the junction. A nearly perfect branching point is made by a reactive ion etch with two overlapping mask strips. An asymmetric Y-junction designed to function as a mode splitter is realized with this technique. It shows an improvement of 4-8 dB in mode splitting over a version made with a single masking layer. This agrees with BPM-simulations on the effect of blunting in these Y-junctions.<>
Keywords :
III-V semiconductors; gallium arsenide; indium compounds; integrated optics; masks; optical waveguides; optical workshop techniques; photoresists; BPM-simulations; InGaAsP-InP; InGaAsP/InP; asymmetric Y-junctions; blunting; double masking; fabrication procedure; integrated optics; mode splitter; mode splitting; nearly perfect branching point; overlapping mask strips; overlapping masking layers; reactive ion etch; resist; sharp vertices; Couplers; Dry etching; Integrated optics; Optical device fabrication; Optical polarization; Optical switches; Resists; Silicon compounds; Strips; Wet etching;
Journal_Title :
Photonics Technology Letters, IEEE
