Thermally stimulated currents in organic monomolecular layers
Creators
- 1. Centre d'Etudes Nucleaires de Saclay, Services d'Electronique de Saclay, Service Electronique pour la Recherche et les Applications, Section d'Assistance Electronique a la Recherche Fondamentale, Laboratoire d'Etudes et de Recherches Avancees (France)
Description
The polarization phenomenon in metal/organic monomolecular layer/metal devices was studied by thermally stimulated currents (T.S.C.). The thermal current peaks for various experimental conditions (temperature, electric field, polarization time, dielectric thickness), show that the polarization in ortho-phenanthroline with three stearic chains is due to local charge displacements between two potential wells. We found that these charge displacements vary as the thickness increases, which implies that the dielectric structure changes when the number of monolayer increases. The high values of activation energies (1.1 eV to 3.4 eV) determined from the current peaks suggest that the moving charges are ions. In ortho-phenanthroline multilayers, at room temperature, we have not observed a notable space charge phenomenon due to ion displacements from one electrode to the other. (authors)
Abstract (French)
On a etudie par la methode des courants stimules thermiquement la polarisation de structures metal-isolant-metal realisees avec des couches monomoleculaires organiques. En faisant varier les conditions experimentales: temperature, champ electrique, temps de polarisation, epaisseur du dielectrique, on montre que l'orthophenanthroline a trois chaines steariques presente une polarisation due a des deplacements de charges entre deux positions d'equilibre. La distance de migration de ces charges varie avec le nombre de couches ce qui implique une modification de la structure du dielectrique lorsque le nombre de couches augmente. Les valeurs elevees des energies d'activation (1.1 a 3.4 eV) donnees par les pics de courant stimule thermiquement indiquent que le phenomene de polarisation est d'origine ionique. Par contre on n'observe pas a temperature ambiante la formation d'une charge d'espace notable due au transport d'ions d'une electrode a l'autre sous l'effet du champ electrique dans les multicouches d'orthophenanthroline. (auteurs)Files
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Additional details
Additional titles
- Original title (French)
- Etude de la polarisation de couches monomoleculaires organiques par la methode des courants stimules thermiquement
Publishing Information
- Imprint Pagination
- 26 p.
- Report number
- CEA-N--1675
INIS
- Country of Publication
- France
- Country of Input or Organization
- France
- INIS RN
- 49081573
- Subject category
- S36: MATERIALS SCIENCE;
- Descriptors DEI
- ACTIVATION ENERGY; CAPACITORS; CHARGE TRANSPORT; COMPOSITE MATERIALS; CRYOSTATS; DEPOLARIZATION; DIELECTRIC MATERIALS; ELECTRIC DIPOLES; ELECTRIC FIELDS; PHENANTHROLINE-ORTHO; POLARIZATION; RELAXATION TIME; SPACE CHARGE; TEMPERATURE DEPENDENCE; TIME DEPENDENCE; VACUUM COATING
- Descriptors DEC
- AROMATICS; AZAARENES; CONTROL EQUIPMENT; DEPOSITION; DIPOLES; ELECTRICAL EQUIPMENT; ENERGY; EQUIPMENT; HETEROCYCLIC COMPOUNDS; HYDROCARBONS; MATERIALS; MULTIPOLES; ORGANIC COMPOUNDS; ORGANIC NITROGEN COMPOUNDS; PHENANTHROLINES; REAGENTS; SURFACE COATING; THERMOSTATS
Optional Information
- Notes
- 18 refs.; Available from the INIS Liaison Officer for France, see the INIS website for current contact and E-mail addresses