Optical materials for printed interconnects and sensors

This work explores additive manufacturing technology to fabricate hybrid circuits comprising of optical and electronic materials as photonic and electrical interconnects, respectively. Several polymeric optical materials have been investigated (including SU8, PDMS, UV15 and Norland adhesives) as waveguides directly printed on commercial circuit boards such as FR4 and Rogers TC600. An optical waveguide printed over RF (radio frequency) transmission lines and surface mount electronic components is demonstrated. As an application, the waveguide is used as an alternative to traditional electrical interconnects to control an RF switch for routing an RF signal from a single source to different locations. This work also investigates the feasibility of printed polymeric waveguides as a sensing platform for monitoring humidity and temperature changes in electronic circuits. Results show that the SU8 waveguide responds significantly to change in temperature and humidity and the response is appropriate for logistics applications such as cold chain supply.