Photonic Crystals
Interference Lithography produces periodic structures with perfect quality. Using DUV lasers we are able to fabricate pitches in the range of typical photonic crystals for visible and infrared light.
Photonic crystals were first proposed by Prof. Eli Yablonovitch. They are crystalline periodic structures allowing the control of the state of light just like electrons can be manipulated in semiconductors. Photonic Crystals can be found today already in efficient lasers, light emitting diodes and solar cells. They can be used to confine light and miniaturize communication components like filters or modulators much more compared to standard waveguide based photonics.
We fabricate photonic crystals and etch mask for further pattering on various substrates. Those crystals have been used for silica and silicon based photonics and surface enhanced raman scattering structures.
- 550 nm pitch quasi hexagonal photonic crystal gratings
Distributed Feedback Structures
Distributed feedback structures are often found in integrated photonic devices. They serve as wave length selective mirrors in resonators or filters. A high quality is achieved by using several 100 µm long gratings which are usually difficult to manufacture. Fabrication technology which produce unintentional stitching create unwanted phase jumps or passbands in the filter characteristic.
With Interference Lithography error free gratings can be fabricated. AMO has demonstrated this by fabricating mm long gratings on top of SOI ridge wave guides for 1,55 µm lightwave technology.
