Figure 6
From: 3D-printed microelectronics for integrated circuitry and passive wireless sensors
Fabricated devices. (a) Cross-sectional view of a fabricated smart cap; (b) optical image of a completed 3D cap structure with a one-cent coin; (c) the fabricated cap after the liquid metal filling process; and (d) magnified optical image showing the spiral inductor around the top surface of the cap. Test results of wireless LC tank sensors from the RF reader: (e) magnitude versus frequency curves with milk at 22 °C after 0, 12, 24, and 36 h; (f) resonance frequency versus time for a milk sample at 4 °C and a milk sample at 22 °C.
