Published online by Cambridge University Press: 19 August 2014
In this paper, we report on a new micropillar sensor array that is stretchable, flexible, and has high sensitivity in the tactile sensing regime (<10 kPa). The sensor array is capable of detecting deformation modes other than pressure such as shear and planar extension. The capacitance-type sensor is fabricated using soft nanolithography whereby the micropillars are individually electroded using a sputtering technique. Buckled gold electrodes are used in this study to enable large sensor stretches up to 55%. Three micropillar aspect ratios were considered in this work (1:1, 1:2, 1:3). Here we present the highest reported sensitivity [0.8 kPa-1] of a capacitance type flexible/stretchable sensor. Our results show that this sensor is also able to detect very low pressures down to 5.4 Pa, which is in the range of ultra-low detection pressures recently reported. Finally, the microstructured sensor array naturally lends itself to the development of pixel-type pressure sensors. We present preliminary results for a 25 pixel array.