A hybrid OTFT-SPR system for simultaneous electronic and optical sensing

Area of Science:

• Materials Science
• Nanotechnology
• Sensor Technology

Background:

• Existing Surface Plasmon Resonance (SPR) and Field-Effect Transistor (FET) systems face limitations in reliability and integration.
• Combined SPR/FET devices require improvements for enhanced performance and broader applicability.

Purpose of the Study:

• To develop an advanced multivariable sensing platform integrating a flexible extended-gate organic thin-film transistor (ExG-OTFT) with SPR readout.
• To overcome limitations of previous combined systems through spatial separation and a pseudo-reference electrode for improved reliability.
• To demonstrate simultaneous electrical and optical detection for real-time monitoring of surface processes.

Main Methods:

• Fabrication of a flexible ExG-OTFT device compatible with SPR instrumentation.
• Spatial separation of the sensing surface from the transistor body.
• Implementation of a pseudo-reference electrode for enhanced system stability.
• Real-time monitoring of polyelectrolyte multilayer formation using simultaneous electrical and optical detection.

Main Results:

• Demonstrated simultaneous electrical and optical detection capabilities.
• Achieved improved system reliability via spatial separation and pseudo-reference electrode.
• Showcased the sensor's sensitivity to mass uptake (SPR) and charge carrier distribution (electronic).
• Validated the ExG-OTFT architecture's compatibility with commercial SPR instruments.

Conclusions:

• The developed flexible SPR/FET sensor offers a scalable, robust, and cost-effective solution for multivariable sensing.
• This technology enables straightforward upgrades to existing SPR instrumentation for enhanced functionality.
• The platform holds significant potential for advancing next-generation sensing applications across diverse fields.