Two-photon laser lithography of photonic microstructures in photoresist SU-8

High quality three-dimensional micro-and nano-structures were fabricated in photoresist SU-8 by two-photon laser lithography. Extended periodic microstructures with so-called woodpile architecture are demonstrated to have good quality and exhibit fundamental and higher-order photonic stop-gaps in the infrared wavelength range of 2.0-8.0 μm. These SU-8 structures can be used as photonic crystal templates suitable for infiltration by high refractive index materials. To illustrate the resolution limit of SU-8 material, we also demonstrate fabrication of SU-8 nanorods with ultrahigh resolution of about 30 nm.