Characterization of semiconducting organic molecules devices by electric impedance/capacitance spectroscopy technique

• Grant number: 09/15848-0
• Support Opportunities: Scholarships abroad - Research
• Effective date (Start): February 01, 2010
• Effective date (End): March 19, 2010
• Field of knowledge: Physical Sciences and Mathematics - Physics - Condensed Matter Physics
• Principal Investigator: Lucas Fugikawa Santos
• Grantee: Lucas Fugikawa Santos
• Host Investigator: Heinz von Seggern
• Host Institution: Instituto de Biociências, Letras e Ciências Exatas (IBILCE). Universidade Estadual Paulista (UNESP). Campus de São José do Rio Preto. São José do Rio Preto , SP, Brazil
• Research place: Technische Universität Darmstadt (TU Darmstadt), Germany

Abstract

In this project, the electrical properties of pentacene-based optoelectronic devices will be studied in metal/pentacene/metal structures using different metals as electrodes, different thickness of the active layer and at different temperatures. The aim of the project is to understand the charge-carrier injection and transport processes in organic semiconductors by means of current-voltage (I-V) and impedance/capacitance spectroscopy techniques. Particularly, the negative capacitance (NC) effect, which occurs at certain experimental conditions in the low-frequency region, will be investigated. The results will be analyzed qualitatively using theories which consider space-charge effects and charge-carrier recombination in the bulk. The elaboration of a quantitative model for the negative capacitance effect in organic semiconductors, based on the analysis of the preliminary data, is also intended. (AU)