Flexible Sputter-Deposited Carbon Strain Sensor

In this letter, we report a piezoresistive amorphous carbon strain sensor fabricated on a flexible polyimide substrate. Amorphous carbon was sputter-deposited onto a 125-μm-thick polyimide film and the strain gauges were tailored using laser micromachining. The strain sensors were tested by using a cantilever setup to obtain sensitivity, hysteresis, repeatability, and dynamic response. Gauge factors in the range of 6-9 have been achieved.