Fig. 1. The key technologies of IoT
Fig. 2. Schematic of capacitive humidity sensor
Fig. 3. Schematic of IDT sensor Structure
Fig. 4. Fabrication Process of the capacitive humidity sensor
Fig. 5. Photograph of the capacitive humidity sensor
Fig. 6. Fabrication Process of the capacitive humidity sensor
Fig. 7. Schematic of the measurement system
Fig. 8. Capacitance variation vs. relative humidity
Fig. 9. The hysteresis of IDT capacitive humidity sensor
References
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