CROSSED GRATING PHOTONIC CRYSTALS AND MULTIPLE EXPOSURE PROCESSES FOR MAKING THEM

摘要

Methods of making crossed grating photonic crystals using either two simultaneous or two sequential interferometric exposures are disclosed. The formation of a patterned crossed grating photonic crystal by photolithographically forming an in situ masking element using a photomask (46) to expose a photoresist (44) overlying an opaque film (42) and using th e patterned resist (52) as a mask to etch the metal layer to form a patterned metal film (56) on the substrate (40). The patterned metal film is then coat ed with a second resist (58) and exposed to two simultaneous interferometric exposures (60) through the backside of the substrate (40) and then is developed to form the pattern shown in figure (5I). The resulting articles m ay be used a waveguides, couplers, splitters and wavelength division multiplier s.