An array of field-effect nanoplate SOI capacitors for (bio-)chemical sensing

Area of Science:

• Materials Science
• Nanotechnology
• Electrical Engineering

Background:

• Development of individually addressable sensor arrays is crucial for high-throughput analysis.
• Silicon-on-insulator (SOI) technology offers a robust platform for microelectronic devices.
• Capacitive biosensors provide a label-free detection method for various analytes.

Purpose of the Study:

• To develop an array of individually addressable nanoplate field-effect capacitive biosensors using SOI technology.
• To demonstrate the feasibility of these sensors for detecting pH, penicillin concentration, polyelectrolyte multilayers, and DNA hybridization.
• To showcase the potential of nanoplate SOI capacitors as a versatile structural element for field-effect biosensors.

Main Methods:

• Fabrication of an SOI-based sensor array with trench isolation in the top silicon layer.
• Implementation of addressable biasing and electrical readout for individual capacitive biosensors.
• Demonstration of sensor functionality through detection of pH, penicillin, polyelectrolyte formation, and DNA hybridization.

Main Results:

• Successful development of an addressable array of electrolyte-insulator-silicon-on-insulator (EISOI) capacitive biosensors on a single SOI chip.
• Demonstrated label-free detection of pH, penicillin, polyelectrolyte multilayers, and DNA hybridization events.
• Observed a significant potential change (~120 mV) upon DNA hybridization with matched DNA, indicating high sensitivity.

Conclusions:

• The developed nanoplate SOI capacitive sensor array enables addressable biasing and differential-mode measurements.
• The proposed SOI capacitor structure is a promising platform for creating diverse field-effect biosensors.
• This technology facilitates label-free monitoring of biological interactions, such as DNA hybridization.