Versatile disposable FET-based biosensors

Project ID: 1762-AP
Available for licensing

Background

Conventional CHEMFETs (chemical field effect transistors) are silicon MOSFETs with the gate uncovered to make it chemically sensitive. These gates, made of poly-silicon or metal which are replaced with a chemically sensitive metal, are widely used but are not very effective. Furthermore, due to inefficiencies in removing trapped charges/dipoles after a sensing event, CHEMFET sensors experience a lot of drift in their characteristics with regard to time.

Invention Description

The key difference from established silicon CHEMFET technology is that CHEMFETs use channel charge modulation by dipoles (which have a net charge of zero), whereas in our device we use trapped positive charges, which produce a much greater conductivity modulation. This results in a performance improvement of a factor of 10X to 100X in comparison with existing technology (tested with air-based analytes). A similar increase in sensitivity is expected to be obtained in other media as well. The invention covers inorganic-inorganic four-terminal devices for vapor/gas sensing, as well as inorganic-inorganic four-terminal devices for sensing in aqueous ambients

Benefits

Outperforms traditional CHEMFETs by a factor of 10 in terms of magnitude of response
Observed response in the chemical memory mode 10 to 100 times more intense
Can run the sensor in many modes, multiparameter (3-in-1 sensor)
Based on established technology
Low cost, disposable, and easy to manufacture (combined with thin film technology)
Suitable for various ambients
Can be integrated at a system level for RFID applications

Features

Given its advantages, this technology can still function as a traditional CHEMFET.
The sensors can be refreshed after a sensing event.
The unique sensing mode "both on" appears to be the most sensitive of all the multiple sensing mechanisms present.

Market Potential/Applications

Water testing, water quality monitoring, glucose level testing, lactic acid level monitoring, disease detection and diagnostics, and various industrial uses

Development Stage

Lab/bench prototype

UT Researcher

Ananth Dodabalapur, Ph.D., Electrical and Computer Engineering, The University of Texas at Austin

OTC Contact Information

Jitendra Jain, Licensing Specialist
jjain@otc.utexas.edu
512-471-9055