Loss reduction of electron-beam lithography fabricated strip wire waveguide bends

The losses in integrated photonic bends relies first and foremost on the index contrast between the core and the cladding. Low index contrast materials require bend radii of ∼1 mm or more. Although mass-fabication of photonic components relies mainly on optical lithography, electron-beam lithography (EBL) is a more suitable tool for research purposes. The direct writing and resolution of an electron-beam lithography system presents itself as a problem however when the digitization of the mask file leads to segmented curves in an EBL exposure. We aim to minimize the losses caused by this segmentation by optimizing the generation of the mask file as well as tuning the parameters to the available electron-beam lithography machine. The waveguide dimensions are 500 nm × 220 nm.