Trace-Level, Multi-Gas Detection for Food Quality Assessment Based on Decorated Silicon Transistor Arrays

Area of Science:

• Materials Science
• Chemical Engineering
• Sensor Technology

Background:

• Real-time monitoring of gases is crucial for applications like food spoilage detection.
• Existing gas sensing technologies often require high temperatures or lack multiplexing capabilities.

Purpose of the Study:

• To develop a selective, sensitive, and simultaneous room-temperature gas detection system.
• To create a portable and integrated sensor array for real-time monitoring of food decomposition gases.

Main Methods:

• Fabrication of an integrated array of multiple silicon-based chemical-sensitive field-effect transistors (CSFETs).
• Decoration of CSFETs with ruthenium, silver, and silicon oxide for detecting ammonia, hydrogen sulfide, and humidity.
• Integration of the CSFET array with a printed circuit board for a portable system.

Main Results:

• Stable room-temperature responses to ammonia (NH3), hydrogen sulfide (H2S), and humidity were achieved.
• Sensitive detection limits down to 10 parts per billion (ppb) for NH3 and H2S were demonstrated.
• The sensor array successfully monitored gases generated by decomposing food in real-time.

Conclusions:

• The developed CSFET sensor array provides a cost-effective and reproducible platform for ambient gas measurement.
• This technology is well-suited for practical food safety applications requiring real-time monitoring.
• The silicon-based manufacturing approach enables scalable and low-cost production.