Traditional photolithography begins with single-photon absorption of patterned light by a photo-initiator to locally expose a resist. In two-color photo-inhibition/initiation (2PII) lithography, these exposed regions are confined by a surrounding pattern of inhibitors generated by one-photon absorption of a second color in a photo-inhibitor. The specific research goal of this proposal is to test the conjecture that the resolution limit of 2PII lithography is enforced by inhibitor diffusion. This will be accomplished by incorporating the 2PII chemistry into thick, solid resists which self-develop index structures in response to 3D direct-write lithography. The resulting solid, photo-patternable materials are foundations for 3D optoelectronic devices in the areas of silicon photonics packaging and high-performance data storage.
Intellectual Merit The current generations of both semiconductor lithography and optical data storage are at the technological limits of resolution. Although these applications are at opposite ends of the cost spectrum, both industries share an uncertain future in the face of the diffraction limit. By combining 3D resolution superior to existing nonlinear absorption methods with the high sensitivity of photo-resist, the proposed lithography method has the potential to transform optoelectronic micro- and nano-fabrication across a broad spectrum of technologies.
Broader Impact The research will be integrated into education via the development of an undergraduate optics sequence featuring senior-level design, fabrication and test of 3D optoelectronic and nanophotonic circuitry via software-controlled lithography and self-developing materials. This sequence will be founded on teaching methods featuring design as the core skill of engineering
