Date/Time: 04-04-2018 - Wednesday - 05:00 PM - 07:00 PM
Edgar Guerrero1 Jimin Maeng1 Sheelpi Pati1 Gerardo Gutierrez2 1 Walter Voit1

1, University of Texas at Dallas, Richardson, Texas, United States
2, Centro de Investigaciones de Optica, Leon, Guanajuato, Mexico

Wireless implantable technology has the potential of revolutionizing the medical field, facilitating the use of complex circuitry in soft, miniaturized packages. One enabling component of wireless implants is a Schottky diode rectifier based on a semiconductor suitable for thin-film applications. Among the available flexible semiconductors, amorphous Indium-Gallium-Zinc-Oxide (IGZO) has shown versatile properties, with its high electron mobility >10 cm2/Vs and low fabrication temperature < 200 Celsius. In this study, we present platinum (Pt)-IGZO Schottky contact diodes fabricated on a thermoset thiol-ene/acrylate shape memory polymer (SMP) substrate. The mechanical properties of the polymer are tailored to enhance biocompatibility and adhesion between metal gate contact and SMP substrate. The resulting devices can therefore be stiff enough to facilitate device implantation and then soften in vivo to approach internal body tissue moduli. Based on a preliminary study on glass substrates, UV-ozone treatment on the Schottky metal surface maximizes rectification ratios to ~106 by adjusting treatment to 10 min at 100 degrees Celsius. The present devices fabricated on the SMP substrate undergo the specified UV-ozone treatment and are then annealed for 1 hour at 200 Celsius in an oxygen environment. These devices exhibit a maximum rectification ratio of ~104 on the SMP substrate. Comparisons of 60 and 120-nm sputtered IGZO thicknesses show that on/off current ratios tend to be higher for diodes with a thinner layer of semiconductor. Discrepancies in the diode performance between the glass substrate and the polymer substrate indicate that further studies are required to enhance the properties of the Schottky diodes on SMP. Future work includes characterization of these devices in a physiological medium and integration with metal-insulator-metal (MIM) capacitors to form energy harvesters. The implementation of these devices on a deformable softening polymer may pave the way for miniaturized wireless medical implants technology.

Meeting Program

5:00 PM–7:00 PM Apr 4, 2018 (America - Denver)

PCC North, 300 Level, Exhibit Hall C-E