An all-two-dimensional Fe-FET retinomorphic sensor based on the novel gate dielectric In₂Se_3-O

Area of Science:

• Materials Science
• Condensed Matter Physics
• Nanotechnology

Background:

• Two-dimensional (2D) ferroelectric field-effect transistors (Fe-FETs) are promising for advanced electronics like memory and neuromorphic computing.
• Current 2D ferroelectric materials (e.g., α-In2Se3) require integration with 3D dielectrics, causing device compatibility issues.
• There is a need for purely 2D gate dielectric materials compatible with semiconductor manufacturing.

Purpose of the Study:

• To develop a new 2D gate dielectric material for all-2D Fe-FETs.
• To address the limitations of existing 2D ferroelectric semiconductors.
• To create a high-performance photodetector with integrated functionalities.

Main Methods:

• Utilized oxygen plasma treatment to synthesize a novel 2D gate dielectric material.
• Fabricated an all-2D Fe-FET photodetector using the new dielectric and α-In2Se3.
• Characterized the dielectric properties (equivalent oxide thickness, leakage current) and device performance (on/off ratio, detectivity).

Main Results:

• The novel 2D dielectric exhibits an equivalent oxide thickness < 0.15 nm and low leakage current (< 2 × 10^-5 A cm^-2 at 1 V).
• The fabricated all-2D Fe-FET photodetector achieved a high on/off ratio of ~10^5 and detectivity > 10^13 Jones.
• The device demonstrated integrated perception, memory, and computing characteristics.

Conclusions:

• The developed 2D dielectric material is compatible with complementary metal-oxide semiconductor processes.
• The all-2D Fe-FET photodetector shows excellent performance and multifunctional capabilities.
• This technology holds potential for applications in artificial neural networks for visual recognition.