Multiphoton Absorption Polymerization Fabricated Waveguides

Standard lithographic fabrication techniques are not well adapted to making 3D optical structures. We are pursuing the use of multiphoton absorption polymerization (MAP) to create polymer optical waveguide structures. In MAP, the simultaneous absorption of two or more photons of near-infrared radiation is used to drive photopolymerization of a viscous prepolymer resin. By scanning the focal volume through a desired 3D pattern and then washing away the unexposed resin, it is possible to sculpt arbitrarily complex, 3D structures with a resolution better than 100 nanometers.  We are using MAP to fabricate microring resonators and other optical structures in highly-crosslinked acrylic polymers.

Polymerization occurs only near the focal point
where laser intensity is high.

MAP fabricated add-drop filters

SEM picture showing the
smoothness of waveguide
walls in a MAP fabricated
polymer waveguide.

Tapered end facet for optimized
coupling to optical fiber.



Example (a) through-port and (b) drop-port spectra for a polymer micro-ring resonator add-drop filter fabricated using MAP.

“Polymer Waveguides and Advances in Fabrication Techniques,”  W. N. Herman, Y. Leng, V. Yun, W.-Y. Chen, V. Van, T. Ding, L. Lucas, L. Li, E. Gershgoren, J. T. Fourkas, P.-T. Ho, J. Goldhar, invited talk at the OSA Topical Meeting on Integrated Photonics and Nanophotonics Research Applications (IPNRA), July 2007, Salt Lake City.

“Microring Resonators Using Multiphoton Absorption Polymerization,” Linjie Li, Wei-Yen Chen, Tie-Nan Ding, Warren Herman, P-T Ho, John Fourkas, Frontiers in Optics/Laser Science (FiOLS), September 2007, San Jose.

"High-Performance Microring Resonators Fabricated with Multiphoton Absorption Polymerization," Linjie Li, Erez Gershgoren, George Kumi, Wei-Yen Chen, P.-T. Ho, Warren N. Herman, and John T. Fourkas, Advanced Materials 20, 1(2008).

“Fabrication of High-Performance Optical Devices Using Multiphoton Absorption Polymerization,” Linjie Li, George Kumi, Rafael R. Gattass, Erez Gershgoren, Wei-Yen Chen, P.-T. Ho, Warren N. Herman, and John T. Fourkas, in press in Organic Thin Films for Photonics Applications,  W.N. Herman, S. Flom, and S. Foulger, eds. (ACS Symposium Series 1039, 2010), Chap. 9.