Fabrication of single-walled carbon nanotube flexible strain sensors with high sensitivity

This work demonstrates a fabrication technique of high sensitivity flexible strain sensors at room temperature. The grown well-aligned millimeter-long single-walled carbon nanotube (SWCNT) was transferred from the silicon substrate to the pretrenched flexible substrate. The sensor design allows effective adhesion between SWCNT and flexible substrate for SWCNT lengthwise strain and piezoresistivity change. Experimental results show that the sensor achieves a high strain resolution of 0.004%. The measured piezoresistive gauge factor of the flexible sensor is 269. The demonstrated fabrication technique of flexible sensors shows advantage of high sensitivity, high quality, and is suitable for mass production.