Low-Cost, High-Throughput Roll-to-Roll Printing of Integrated Photonic Devices on Flexible Substrates via a Combination of Nanoimprinting and Ink-Jet

ABSTRACT: In this program, Omega Optics, Inc., in collaboration with the University of Michigan Ann Arbor and the University of Texas at Austin, proposes to develop integrated photonic devices by using a combination of high-rate R2R nanoimprint lithography (R2RNIL) and R2R ink-jet printing. Patterning of photonic devices with sub-wavelength (<100nm) features utilizing R2RNIL will be demonstrated in an efficient, cost effective and manufacturably viable method on large area flexible substrates. Such a technology not only eliminates the bottleneck of e-beam lithography in terms of reducing time and cost, but also offers high rate (>1m/min) continuous processing. The customized R2R high-rate ink-jet print engine will provide precise placement of several functional materials, including polymers, organics, nanowires, nanotubes, nanoparticles etc, in order to form a fully functional integrated system. During the Phase I program, we proved the feasibility of our printing technology. A 2x2 TO polymer switch was developed and switching speed at 1kHz was demonstrated. We also developed an EO polymer modulator, and demonstrated operation up to 10GHz. Accurate alignment was achieved via utilization of alignment marks and an in-house developed pattern recognition software. Additionally, using a continuous R2R phase-shift lithography technique, we developed transparent conductive electrodes in aluminum, and demonstrated high transmittance of 92%. In Phase II, we will further customize the material systems and tools for R2RNIL and R2R ink-jet printing. Key manufacturing related issues, such as in-line alignment and quality control, will be addressed. Light coupling schemes, for reliably packaging the devices, will also be developed. Using printing, several photonic components, such as TO switch based reconfigurable true-time-delay lines, EO modulator arrays, light emitting diodes, acoustic detectors, reconfigurable logic, etc will be further developed and characterized. Following optimization, integration of these components to form a multifunctional communication system on a flexible substrate will also be performed. The reliability of the components and systems will be tested and improved in order to enable direct injunction of the devices into military and commercial products. These objectives are targeted at developing unique large area multifunctional integrated photonic system architectures on flexible substrates at high rates that can only be achieved with printing. BENEFIT: Potential application areas of roll-to-roll printing process for optical components on flexible substrates include a) optical waveguide arrays for optical bus architecture, clock distribution, ring resonators; b) photonic crystal based devices for resonators, optical buffers, optical delay lines, add/drop filters, true-time-delay lines for RF antenna feed systems, RF modulators, superprisms; c) grating structures for add/drop filters, delay lines, optical buffers, light coupling structures for optical waveguides; d) patterning doped/stacked multi-material nanomembranes to form photodetector arrays, image detectors, solar cells; e) plasmonic structures for high efficiency flexible solar cells, f) light sources such as LEDs etc. Other areas where such a technology is expected to have a huge impact over the next ten years include healthcare, transportation industry, security, agriculture and education, military and consumer goods. Our proposed work can realize continuous manufacturing of novel flexible photonic components and systems, thus furthering the domain of potential useful applications and increasing revenue.