Patent ID: 7820365

Claim:
A method to fabricate a tilted logpile photonic crystal, comprising: providing a substrate coated with a photoresist; providing a lithographic mask comprising a pattern of mask openings to pattern a tilted logpile structure in the photoresist with an incident beam from a collimated X-ray source; mounting the mask spaced a distance from the surface of the photoresist; tilting the mounted mask and substrate at a crystallographic symmetry angle toward the incident beam and aligning the incident beam with the mask openings; rotating the mounted mask and substrate through a stitching angle about the mask normal; exposing the photoresist to the incident beam through the mask openings to pattern a first half of the tilted logpile structure in the photoresist; rotating the mounted mask and substrate by 180 degrees about the mask normal; and exposing the photoresist to the incident beam through the mask openings to pattern a second half of the tilted logpile structure in the photoresist, thereby forming a tilted logpile structure patterned in the photoresist.