Ultra-Sensitive OPTO-Piezoresistive Sensors Utilising 3C-SiC/Si Heterostructures

Here we report for the first time an ultra-sensitive opto-piezoresistive effect in cubic silicon carbide (3C-SiC) nanofilms grown on silicon (Si). The sensitivity of the sensor was significantly enhanced by coupling the photovoltaic effect and controlling distribution of hole/electron in semiconductors. By applying this method, the gauge factor (GF) of strain sensors can be improved at least three orders of magnitude compared to conventional MEMS sensor. A GF of approximately 58,000 was observed, which is the highest GF reported for semiconductor piezoresistive sensors to date. Consequently, our findings can be deployed to develop ultra-sensitive mechanical sensors and MEMS/NEMS sensing applications.