Fabrication and Characterization of Inkjet Printed Flexible Fractal-Type Temperature Sensor

In the present research, we have presented the fabrication and characterization of inkjet printed temperature sensor. The sensor was designed as a Sierpinski curve of width 300 µm and 9, 27 and 81 fractals. The sensors were printed with an inkjet printer on Kapton, a thermally stable flexible substrate using silver nanoparticles based ink. The width of the printed sensor was 318 µm ± 2 µm as measured by profiler. The elemental analysis of printed sensors confirmed the presence of 98 wt% of silver nanoparticles. The electrical resistance of the sensors was measured at temperature (30–100) °C and results indicated the linear relation of resistance with temperature. The performances of Sierpinski curves were compared by measuring sensitivity and temperature coefficient. Higher sensitivity and temperature coefficient of resistance is 0.3760 (Ω/°C) and 0.009 (°C−1) for the sensor with 81 fractals. These fractal-based sensors on flexible substrate can find promising application in on-body health sensors.