Nanometre-thin indium tin oxide for advanced high-performance electronics

Area of Science:

• Materials Science
• Semiconductor Physics
• Nanotechnology

Background:

• Indium tin oxide (ITO) is a transparent conductive oxide with limitations in semiconducting applications due to degenerate doping.
• Existing metal oxides and 2D materials face challenges in scaling and performance.

Purpose of the Study:

• To develop high-performance transistors using ultra-thin ITO channels.
• To overcome the limitations of ITO in semiconducting applications.
• To explore ITO's potential for advanced low-power electronics.

Main Methods:

• Fabrication of short-channel active transistors with ultra-thin (4 nm) ITO channels.
• Integration with a high-quality lanthanum-doped hafnium oxide dielectric (0.8 nm equivalent oxide thickness).
• Characterization of transistor performance, including short-channel immunity, logic inverter gain, and radiofrequency capabilities.

Main Results:

• Demonstrated short-channel immunity with a subthreshold slope of 66 mV/decade and off-state current <100 fA/μm.
• Achieved high on/off ratios up to 5.5 × 10^9.
• Exhibited high gain (178) in logic inverters at 0.5 V supply and radiofrequency performance exceeding 10 GHz (fT and fmax).

Conclusions:

• Ultra-thin ITO channels, combined with advanced dielectrics, offer competitive performance compared to existing materials.
• ITO's properties are promising for scaling below 5 nm for next-generation low-power electronics.
• This work unlocks new possibilities for ITO in advanced semiconductor device applications.