Stabilization of organic thin film transistors behaviour via ion-implantation
oral presentation: 2010-08-27 09:50 AM – 10:10 AM
Last modified: 2010-06-13
Abstract
The remarkable advances recently made in the development of organic semiconductor devices prospect challenging applications in the field of low-cost, flexible, lightweight, and conformal electronics
The focus of this work is to investigate the potential use of low energy ion implantation (N and Ne) in the reduction and control of the degradation of organic semiconducting materials employed as active layers in Organic Thin Film Transistors (OTFTs). The molecular structure of organic compounds such as pentacene, is unavoidably modified by exposure to atmosphere (i.e. to oxygen and water) and their electronic transport properties may be greatly degraded. We investigated how exposing OTFTs to a controlled low-energy ion implantation affects the active organic thin film within the field effect device. We have characterized the modification induced on the structural and electrical transport properties of the organic thin film and of the device as a function of time. We show how, by properly selecting the ion type, energy and dose, the functionality of implanted devices is fully preserved and the device lifetime is greatly extended. In particular, we have assessed by depth resolved XPS analyses that implantation with ions that chemically interact with the organic matrix (e.g. N) leads to the formation of stable charged chemical species that directly, and most importantly, predictably affect the charge transport behavior of the material. These findings suggests how the effects induced by ion implantation on organic thin films extend well beyond the here reported lifetime-enhancing application and open up the way for novel and challenging developments in the realization of organic devices.
Author(s) affiliation:
Piero Cosseddu, Department of Electrical Engineering, University of Cagliari, Italy
Yongqiang Wang, Los Alamos National Laboratory, United States
Roland Schulze, Los Alamos National Laboratory, United States
Anna Cavallini, Department of Physics, University of Bologna, Italy
Zhengfeng Di, Los Alamos National Laboratory, United States
Annalisa Bonfiglio, Department of Electrical Engineering, University of Cagliari, Italy
Michael Nastasi, Los Alamos National Laboratory, United States
*presenting author