Long-period waveguide gratings

Long period waveguide gratings (LPWG) based on a low-loss negative tone epoxy Novolak resin polymer have been fabricated on SiO/sub 2//Si substrate using standard cleanroom processes: UV photolithography and reactive ion etching. A maximum attenuation of -18 dB and a minimum 3 dB bandwidth of 6 nm were measured, and the grating length is as short as 1 cm.