Facet preparation of polymer based optical wavelength filter using mechanical/chemical treatment technique

Abstract

AbstractA photodefinable polymer of benzocyclobutene (BCB 4024‐40) from Dow Chemical™ has been demonstrated as a waveguiding material in a new structure of optical wavelength filter. The filter structure is based on the combination of restricted interference and general interference schemes of multimode interference technique. The filter is capable in optical wavelength filtering particularly for 1550/1310 nm. Because of the photosensitive nature of the polymer, the chemical wet‐etching fabrication technique needs to be adopted. For the purpose of laser coupling, a new facet polishing technique has been proposed and it is based on the combination of mechanical and chemical polishing. It is shown that the fabricated device works well with improved crosstalk of −15.7 dB (1310 nm) and −21.8 dB (1550 nm). © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1301–1313, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26781