Effect of Switching on Metal-Organic Interface Adhesion Relevant to Organic Electronic Devices

Babaniyi Babatope, Akogwu Onobu, Olusegun O. Adewoye, Winston O. Soboyejo

Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, USA.
Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, USA 3Materials Science and Engineering Department, African University of Science and Technology, Abuja, Nigeria Materials Science and Engineering Department, African University of Science and Technology, Abuja, Nigeria.
Department of Physics, Obafemi Awolowo University, Ile-Ife, Nigeria.
Materials Science and Engineering Department, African University of Science and Technology, Abuja, Nigeria.

DOI: 10.4236/ampc.2013.37041                

Abstract

Considerable efforts are currently being devoted to investigation of metal-organic, organic-organic and organic-inorganic interfaces relevant to organic electronic devices such as organic light emitting diode (OLEDs), organic photovoltaic solar cells, organic field effect transistors (OFETs), organic spintronic devices and organic-based Write Once Read Many times (WORM) memory devices on both rigid and flexible substrates in laboratories around the world. The multilayer structure of these devices makes interfaces between dissimilar materials in contact and plays a prominent role in charge transport and injection efficiency which inevitably affect device performance. This paper presents results of an initial study on how switching between voltage thresholds and chemical surface treatment affects adhesion properties of a metal-organic (Au-PEDOT:PSS) contact interface in a WORM device. Contact and Tapping-mode Atomic Force Microscopy (AFM) gave surface topography, phase imaging and interface adhesion properties in addition to SEM/EDX imaging which showed that surface treatment, switching and surface roughness all appeared to be key factors in increasing interface adhesion with implications for increased device performance.

Keywords

AFM; Interface; Adhesion Force; Organic Electronics; Voltage Switching; Organic Memory Devices; Surface Treatment

Conflicts of Interest

The authors declare no conflicts of interest.

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