High-Mobility Flexible Oxyselenide Thin-Film Transistors Prepared by a Solution-Assisted Method

Area of Science:

• Materials Science
• Condensed Matter Physics
• Nanotechnology

Background:

• Two-dimensional (2D) semiconductors offer potential for flexible electronics due to their inherent flexibility and high electrical properties.
• Challenges remain in synthesizing high-mobility 2D semiconducting thin films and fabricating devices efficiently.

Purpose of the Study:

• To develop a facile, rapid, and scalable method for synthesizing high-mobility 2D bismuth oxyselenide (Bi2O2Se) thin films.
• To demonstrate the potential of these Bi2O2Se films in flexible electronic devices.

Main Methods:

• Solution-assisted synthesis involving selenization and decomposition of a bismuth nitrate precursor.
• Precise control of film thickness via spin-coating rotation speed.
• Fabrication and testing of flexible top-gated transistors on Bi2O2Se thin films.
• Transfer of devices onto flexible polyvinyl chloride (PVC) substrates.

Main Results:

• Achieved high Hall mobility of ~74 cm^2 V^-1 s^-1 at room temperature in Bi2O2Se thin films.
• Demonstrated precise thickness control down to few atomic layers.
• Flexible Bi2O2Se transistors exhibited excellent electrical stability on both flat and bent substrates.
• Successful transfer of devices onto flexible PVC substrates.

Conclusions:

• The developed method provides a scalable route to high-quality Bi2O2Se thin films.
• Bi2O2Se is a promising material for high-performance flexible electronics due to its high mobility and stability.
• The facile synthesis and transfer process enhance the potential for practical applications in flexible devices.