Abstract

There has been an increasing interest in using organic polymers to implement waveguide devices. Organic polymers have low intrinsic losses, and devices that use these materials are easy and inexpensive to fabricate. This paper reports the first polymer integrated optical polarizer built on silicon that uses an antiresonant, reflecting optical-waveguide (ARROW) structure.¹ The integrated device consists of a low-index polymer core on top of two interference cladding layers that are deposited on a silicon substrate. Although ARROW structures have low transmission losses for TE polarized light (dB/cm), losses for TM polarized light are large (60 dB/cm), making them excellent integrated optical polarizers. The prototype polymer-rib ARROW polarizer was designed for operation at 820 nm. The first and second interference cladding layers were made up of 0.16 m of Si₃N₄ and 2 m of SiO₂. A commercially available photosensitive polymer, NA 61, was used as the core. A 4 m polymer layer was spin-coated onto the first cladding layer. Rib structures 10 m wide were defined by means of conventional photolithography in the prototype devices. Extinction ratios greater than 40 dB/cm were measured. The performance can be further improved by optimizing the coupling between the source and the rib waveguides.

© 1990 Optical Society of America