Opal-like photonic crystal with diamond lattice

A method to fabricate a diamond structure with a complete photonic bandgap in the near infrared is proposed. The procedure starts by building an opal with body-centered-cubic symmetry composed of two types (organic and inorga nic) of microspheres by means of a microrobotic technique. Then, the organi c particles may be selectively removed to obtain a diamond structure of ino rganic particles. This method can be extended to make diamond inverse opals of silicon with full gap to midgap ratios as large as 13% for moderate fil ling fractions. (C) 2001 American Institute of Physics.