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04:22
Fabrication of Bi2Te3 and Sb2Te3 Thermoelectric Thin Films using Radio Frequency Magnetron Sputtering Technique
Published on: May 17, 2024
Insulating behavior in ultrathin bismuth selenide field effect transistors
Sungjae Cho1, Nicholas P Butch, Johnpierre Paglione
1Center for Nanophysics and Advanced Materials, University of Maryland, College Park, Maryland 20742-4111, United States.
Nano Letters
|April 14, 2011
Summary
Ultrathin topological insulator Bi(2)Se(3) field-effect transistors (FETs) were fabricated. These FETs exhibit n-type behavior and energy barriers up to 250 meV, indicating potential for electronic applications.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Nanotechnology
Background:
- Topological insulators (TIs) possess unique electronic properties.
- Ultrathin films of TIs are crucial for exploring novel quantum phenomena.
- Bismuth selenide (Bi(2)Se(3)) is a prominent TI material.
Purpose of the Study:
- To fabricate and characterize ultrathin field-effect transistors (FETs) using topological insulator Bi(2)Se(3).
- To investigate the electronic transport properties of these ultrathin Bi(2)Se(3) FETs.
- To determine the influence of temperature and gate voltage on conductance.
Main Methods:
- Mechanical exfoliation of Bi(2)Se(3) to create ultrathin films.
- Fabrication of FET devices on SiO(2)/Si substrates.
- Temperature- and gate-voltage-dependent conductance measurements.
Main Results:
- Ultrathin Bi(2)Se(3) FETs demonstrated n-type semiconductor behavior.
- A clear OFF state was observed at negative gate voltages.
- Activated temperature-dependent conductance indicated energy barriers up to 250 meV.
Conclusions:
- Ultrathin Bi(2)Se(3) FETs exhibit promising electronic properties for device applications.
- The observed energy barriers suggest potential for tunable electronic behavior.
- Further research can explore advanced device architectures and functionalities.
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