Skip to Main content Skip to Navigation
Theses

Élaboration et étude de vannes de spin organiques : vers le transport de spin à température ambiante

Mathieu Palosse 1
1 LAAS-MICA - Équipe MICrosystèmes d'Analyse
LAAS - Laboratoire d'analyse et d'architecture des systèmes
Abstract : Organic electronics is a recent and promising research field. Most electronic devices have nowadays a counterpart using organic semiconductor (OSCs) materials based on small molecules : organic electroluminescent diodes (OLEDs), organic field effect transistors (OFETs) or organic solar cells (OPVs). The field of organic spintronics has been rapidly growing since the fabrication of the first organic spin valves in 2002 and 2004. This thesis falls within that context, with aim to fabricate and to study organic spin valves in order to get a better understanding of the mechanisms ruling spin injection and transport in OSCs. Fabricated junctions consist of two magnetic electrodes, which spin polarization is conserved above room temperature, separated by an organic thin film of thickness ranging from 50 to 200 nm. Several molecules were studied for their different electronic properties : tris-(8-hydroxyquinoline)aluminum (Alq3), tetraethyl perylene 3, 4, 9, 10-tetracarboxylate (PTCTE) and benzofurane bithiophene (BF3). Morphological and structural studies were conducted to control the quality of metal/ OSC interfaces. VSM measurements (Vibrating Sample Magnetometer) allowed the verification of the spin valve behavior of the samples, from 10 K to 300 K. Moreover, transport measurements were conducted with or without the presence of a magnetic field, varying the temperature. It allowed the identification of space charge limited transport operation with deep traps, and a hopping type charge transport following the Mott's Various Range Hopping model. Also, alternative fabrication methods of the top electrode were compared to improve the stability of the final devices. Finally, up to 3 % of magnetoresistance was obtained at 5 K for PTCTE and at 40 K for BF3, suggesting that these materials are good candidates for spin polarized transport.
Complete list of metadata

Cited literature [178 references]  Display  Hide  Download

https://tel.archives-ouvertes.fr/tel-00910758
Contributor : Arlette Evrard <>
Submitted on : Thursday, November 28, 2013 - 11:06:07 AM
Last modification on : Thursday, June 10, 2021 - 3:06:19 AM
Long-term archiving on: : Monday, March 3, 2014 - 5:25:34 PM

Identifiers

  • HAL Id : tel-00910758, version 1

Citation

Mathieu Palosse. Élaboration et étude de vannes de spin organiques : vers le transport de spin à température ambiante. Micro et nanotechnologies/Microélectronique. Université Paul Sabatier - Toulouse III, 2013. Français. ⟨tel-00910758⟩

Share

Metrics

Record views

499

Files downloads

2395