9501820 Mayer The primary objective of this project is to stimulate and motivate learning at every level (undergraduate, graduate, post-graduate). In the area of fundamental research, the author proposes to develop a process to fabricate 2- and 3- dimensional (2- and 3-D) photonic crystals for optical wavelengths. The 3-D periodic dielectric structure that will be fabricated is a square-rod structure in the simple-cubic lattice. This scaffold structure has the property that all of the flat faces are at right angles to one another. Intuitively, this implies that the fabrication procedure for this square-rod structure will be much easier than those described for face-centered-cubic lattices. The proposed process relies on the integration of many techniques that are currently being used to fabricate III-V optoelectronic devices. In particular, the 3-D structure will be fabricated from a GaAs/A1As stack grown by molecular beam epitaxy (MBE). Following the growth, a submicron cross-hatched pattern is defined on the sample of the surface using electron-beam lithography. The unprotected areas of the GaAs/A1As stack are removed using reactive ion beam etching (RIBE). To complete the photonic crystal, the compositional structure of the A1As supports is modified and the alternating layers of A1As are removed in a selective etchant. En route to this 3-D result, a 2-D structure will also be fabricated. Both of these photonic crystals will be characterized by the transmission method. The successful demonstration of a 3-D photonic crystal at optical wavelengths would allow the development of a new class of devices that could be used to reflect, trap, guide, and switch light. ***
