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Published on: August 13, 2019
Interfacial polarization phenomena in organic molecular films
Mitsumasa Iwamoto1, Takaaki Manaka
1Department of Physical Electronics, Tokyo Institute of Technology, O-okayama 2-12-l-S3-33, Meguro-ku, Tokyo 152-8552, Japan. iwamoto@pe.titech.ac.jp
Analytica Chimica Acta
|September 1, 2007
Summary
This study explores surface polarization in organic thin films, focusing on molecular orientation and charge displacement. These electrostatic phenomena are crucial for understanding organic electronic devices and tunneling behavior.
Area of Science:
- Dielectrics physics
- Organic electronics
- Surface science
Background:
- Electrostatic phenomena at interfaces are critical for organic electronic devices.
- Surface polarization in organic thin films arises from molecular orientation and charge displacement.
- Understanding these phenomena is key to advancing organic semiconductor applications.
Purpose of the Study:
- To discuss electrostatic phenomena at metal/organic and organic/organic interfaces.
- To analyze surface polarization in organic thin films, considering molecular orientation and charge displacement.
- To explore the implications of surface polarization for single electron tunneling in organic films.
Main Methods:
- Introduction of orientational order parameters to quantify molecular alignment.
- Analysis of surface polarization mechanisms, including dipole alignment and excess charge displacement.
- Extension of the surface Fermi level concept to organic semiconductor/metal interfaces.
Main Results:
- Demonstration of surface polarization due to polar molecule orientation and excess charge displacement.
- Experimental evidence presented for Maxwell displacement current (MDC) and second harmonic generation (SHG) in organic monomolecular films.
- Established a link between surface polarization phenomena and single electron tunneling in organic films.
Conclusions:
- Surface polarization, driven by molecular ordering and charge displacement, significantly impacts organic thin film properties.
- The study provides a framework for understanding electrostatic interactions at organic interfaces.
- Investigated phenomena are relevant for the design and performance of organic electronic devices and tunneling.
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