Table 1.
Comparison of Conventional Rigid Sensors and Emerging Flexible Sensors
| Form factor/ appearance |
|
|
|---|---|---|
| Rigid sensors | Flexible sensors | |
| Performance | ||
| Stretchability | < 1%a,30 | Up to 1000%31,32 |
| Young’s modulusb,33 | 1–200 GPa | 10 kPa–200 GPa |
| Conformability on non-flat surfaces | No | Yes |
| Measurement during mechanical deformation | No | Yes |
| Manufacturing | ||
| Methods | MEMSc techniques | Printing, MEMS techniques, etc. |
| Scale27 | 0.01–0.1 m2 (wafer) | Up to 1–100 m2 (web)28 |
| Single-step throughput27 | 0.001−1 m2 min−1 | Up to 10–1000 m2 min−1d |
| Potential cost per unit area34 |
High |
Low |
| Carbon footprint | High | Low |
| Applications | ||
| Smartphones, autonomous vehicles, industrial robots, etc. | Conformal skin patches, smart textiles, sticker sensors for industrial IoT, supply chain, food, etc. |
a
Stretchability of rigid sensors is approximated as the fracture strains of conventional electronic materials. However, the real stretchability would be smaller taking performance alteration in consideration.
b
Ranges cover the Young’s moduli of common materials (packaging materials included) used in rigid and flexible sensors.
c
MEMS, microelectromechanical systems.
d
Assuming 1 m wide web on a roll-to-roll platform.