Controllable P- and N-Type Conversion of MoTe₂ via Oxide Interfacial Layer for Logic Circuits

Area of Science:

• Materials Science
• Condensed Matter Physics
• Nanotechnology

Background:

• Achieving selective p- and n-type transistors with low Schottky barriers is crucial for advanced electronic devices.
• Current methods for doping 2D materials often lack control or are destructive.

Purpose of the Study:

• To develop an efficient and nondestructive method for type-controllable doping of 2H-MoTe2.
• To demonstrate the fabrication of high-performance transistors and CMOS inverters using this doping technique.

Main Methods:

• Utilizing electron-charge transfer doping by depositing a thin Al2O3 layer on chemical vapor deposition (CVD)-grown 2H-MoTe2.
• Preparing type-controllable MoTe2 transistors and fabricating a homogeneous CMOS inverter on CVD-grown 2H-MoTe2 single crystal.

Main Results:

• Successfully tuned 2H-MoTe2 from p-type to n-type doping.
• Achieved n-type MoTe2 transistors with a low Schottky barrier height (28.4 meV), high on-state current (10 µA), and electron mobility (8.9 cm2 V-1 s-1).
• Demonstrated a CMOS inverter with a high DC voltage gain (9.2) and good dynamic behavior up to 1 kHz.

Conclusions:

• The Al2O3-based electron-charge transfer doping is an effective and nondestructive method for creating type-controllable 2D transistors.
• This approach shows significant potential for realizing efficient and ultrafast 2D transition metal dichalcogenide-based electronic units.