Biological/chemical sensor on basis of organic thin-film transistors

Abstract

The invention discloses a biological / chemical sensor on the basis of organic thin-film transistors. The biological / chemical sensor comprises a substrate, a first gate electrode, a first gate insulating layer, source / drain electrodes, an organic semiconductor layer, a second gate insulating layer, a second gate electrode, a sensitive film and encapsulation layers which are sequentially laminated on one another from bottom to top. A bottom gate transistor which is arranged at the bottom of the biological / chemical sensor is formed by the first gate electrode, the first gate insulating layer, the source / drain electrodes and the organic semiconductor layer and is used as a reference device, a top gate transistor which is arranged on the top of the biological / chemical sensor is formed by the source / drain electrodes, the organic semiconductor layer, the second gate insulating layer and the second gate electrode and is used as a sensitive device, the organic thin-film transistors which are of low-voltage double-gate structures are formed by the top gate transistor and the bottom gate transistor, the top gate transistor and the bottom gate transistor have gate capacitance values which are greatly different from one another, and the organic semiconductor layer has low sub-gap density of states. The biological / chemical sensor has the advantages of low working voltage and cost, high sensitivity, detection target diversity and the like. Besides, the biological / chemical sensor is compatible to large-area high-speed printing / coating preparation processes, can be used for manufacturing wearable or mobile sensors and has a broad application prospect in the field of health monitoring and healthcare medical treatment.

Description

technical field [0001] The invention relates to an organic electronic device, in particular to a biological / chemical sensor based on an organic thin film transistor, and belongs to the technical field of electronic devices. Background technique [0002] The ion-sensitive field-effect transistor (Ion-sensitive field-effect transistor) is based on a field-effect transistor (FET), which is combined with an ion-selective electrode as a sensitive film, and can build a variety of biological / chemical sensors. It has dual characteristics of both electrochemical and transistor. The gate of the device is formed by the ion-sensitive membrane and the electrolyte solution, and the threshold voltage of the transistor is modulated by using the electrochemical potential between the solution and the sensitive membrane that changes with the ion concentration. This threshold voltage modulation effect has a relationship similar to the Nernst formula with the ion concentration, so the sensitivit...

AI Technical Summary

Problems solved by technology

At present, there are many reports on ion-sensitive sensors based on organic thin film transistors. However, its performance still needs to be improved. Very high (generally tens of volts), not conducive to practical sensor applications

In order to reduce the operating voltage of the organic thin film transistor device, the capacitance of the device needs to be further increased, thus sacrificing the room for improving the sensitivity of the device

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