[7a-A203-1~12] 12.4 Organic light-emitting devices and organic transistors

▲ [7a-A203-5] Enhancement of Organic Magnetic Field Effects on Pentacene Thin Film by Covering with Aluminum

〇SongToan Pham¹, Hirokazu Tada¹ (1.Osaka Uni.)

Keywords:magnetic field effect, field effect transistor, pentacene

Magnetic field effects observed in various organic devices, abbreviated as OME, are of great scientific interest because of their large magnetoresistance (MR) up to 10% at room temperature and under small magnetic fields of approximately 10 mT without ferromagnetic contacts [1]. In this work, we studied the bottom contact field effect transistor (FET) based on pentacene, which was reported to have negligible OME without light irradiation [2]. However, when a thin layer of Al (2-3 nm) is deposited on top of the pentacene thin film, the OME is enhanced up to MR= 0.4%. This effect may derive from the traps states generated by the Al layer. This result reveals that the interface between the organic layer and Al layer, as usually seen in diode structure, significantly contributes to the OME.
References:
[1] T. L. Francis, Ö. Mermer, G. Veeraraghavan, and M. Wohlgenannt, New Journal of Physics 6, 185-185 (2004).
[2] T. Reichert and T.P.I. Saragi, Appl. Phys. Lett. 98, 63307 (2011).