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Updated: Jun 22, 2026
14:58
Silicon Metal-oxide-semiconductor Quantum Dots for Single-electron Pumping
Published on: June 3, 2015
Controllable molecular modulation of conductivity in silicon-based devices.
Tao He1, David A Corley, Meng Lu
1Department of Chemistry, Rice University, Houston, Texas 77005, USA.
Journal of the American Chemical Society
|July 3, 2009
Summary
Grafting molecular monolayers onto silicon channels offers a novel method for controlling conductivity in nanoscale devices. This approach mimics traditional doping and gating, enabling precise electronic property modulation.
Area of Science:
- Materials Science
- Nanotechnology
- Solid-State Physics
Background:
- Silicon conductivity relies on mobile charge carriers, tunable via gating and doping.
- Nanoscale device fabrication faces challenges with traditional doping due to inhomogeneities.
Purpose of the Study:
- To investigate the use of covalently grafted molecular monolayers as an alternative to traditional doping and gating in silicon nanodevices.
- To demonstrate controllable modulation of conductivity in pseudo-MOSFETs using molecular grafting.
Main Methods:
- Covalent grafting of molecular monolayers onto silicon channels.
- Characterization of charge transfer and surface band bending.
- Fabrication and testing of pseudo-MOSFET devices.
Main Results:
- Molecular monolayers act as donors or acceptors, influencing silicon's electronic properties.
- Grafting induces doping- and gating-like effects, controllably modulating conductivity.
- Molecular effects were observed to penetrate through a 4.92-μm silicon layer.
Conclusions:
- Molecular monolayers provide a viable paradigm for controlling electronic characteristics in nanodevices.
- This technique offers a solution for precise electronic control at future diminutive technology nodes.
- The study presents a new approach for advanced semiconductor device engineering.
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