Electrohydrodynamic Printed Ultra-Micro AgNPs Thin Film Temperature Sensors Array for High-Resolution Sensing

Area of Science:

• Materials Science
• Nanotechnology
• Sensor Technology

Background:

• Traditional thin film sensor fabrication methods like screen printing, inkjet printing, and MEMS have limitations in achieving sub-10 μm line widths.
• This limitation hinders the fabrication of high-density sensor arrays required for advanced applications.

Purpose of the Study:

• To propose and demonstrate a novel method for preparing ultra-micro thin film temperature sensor arrays using only Electrohydrodynamic (EHD) printing.
• To achieve patterned films with line widths less than 10 μm and high sensor density.

Main Methods:

• Utilized Electrohydrodynamic (EHD) printing to fabricate an ultra-micro thin film temperature sensor array.
• Integrated four sensors within a 450 μm × 450 μm area, achieving line widths below 10 μm and film thicknesses of 150-230 nm.
• Characterized the silver nanoparticle conductive network's porosity (0.86%) and sensor performance over a 17-hour temperature-resistance test.

Main Results:

• Observed significant performance differences among the four fabricated sensors.
• Sensor 3 exhibited superior performance with a fitted linearity of 0.99994 and a Temperature Coefficient of Resistance (TCR) of 937.8 ppm/°C between 20 °C and 120 °C.
• Recorded a low resistance change rate of 0.17% at 20 °C after the 17-hour test, indicating good stability.

Conclusions:

• Electrohydrodynamic (EHD) printing is a viable technique for fabricating high-density, ultra-micro thin film temperature sensor arrays.
• The developed method allows for precise control over sensor dimensions and material deposition.
• Sensor 3's performance highlights the potential for EHD-printed sensors in precise temperature monitoring applications.