Air-Suspended Polymer Rib Waveguides

In order to achieve a high refractive index contrast for air-suspended photonic devices, we present a method for laminating thin polymer films onto structured polymer layers that exhibit an air cavity. By using a flat PDMS stamp, polymer films can be transferred over areas of several hundred square microns. On top of the air-suspended slab a second layer of photoresist can be spun and subsequently every desired photonic structure can be defined by using standard photolithography. Here, to demonstrate the feasibility of our lamination method for polymer photonic devices, we present optical modeling and experimental results of air-suspended single mode rib waveguides. Waveguiding is shown for visible and infrared light and a beam profile for lambda = 1550 nm is presented that underpins single mode behavior of the rib waveguide.