Additive Manufacturing of High-Index Photonic Circuits

"ABSTRACT: Modern electronic and opto-electronic devices are predicated on controlled deposition and patterning of functional material layers (e.g. semiconductors, conductors, and dielectrics). A handful of techniques, including vacuum epitaxy and chemical vapor deposition, in conjunction with lithographic micromachining methods, have long dominated the manufacture of these systems, particularly as feature critical dimensions are driven further into the nanoscale. While these techniques are well-established and routinely deliver reliable and excellent performance, they are expensive to operate and maintain and are relegated to the processing of rigid, planar substrates. A host of new integrated optics and photonics technologies stand to benefit from transitioning the successes of vacuum thin film deposition and lithographic patterning to a mass-producible, conformable optoelectronic device manufacturing platform. Critical to this transformation will be the ability to use low-cost conventional printing technologies to pattern precursors of active-layer materials (e.g. semiconductors with high refractive indices) onto a variety of substrates and subsequently “consolidate” the precursors into photonic circuit components (waveguides, splitters, modulators, amplifiers, filters) and electro-optical devices (energy harvesting devices, conformal antennas, and infrared emitter and sensor arrays, for example). In some applications, a small performance tradeoff may be acceptable for a significant cost savings, but the patterned and consolidated end product performance ultimately must be comparable to its high-cost, traditionally-manufactured counterpart. To enable high-throughput, low-cost manufacturing of photonic circuitry, Nanohmics, Inc., an electro-optics and early-stage-technology development company based in Austin, TX, working in collaboration with industrial and academic partners have formulated a class of high-refractive-index-material inks and developed methods for in-line, direct-write printing and consolidation of the inks into photonic circuit components on large-area, continuous webs."