Evaluation of the influence of changes in the physical parameters of OTFTs and thin film deposition processes in the electrical parameters of the device

• Grant number: 18/16115-5
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: September 01, 2018
• End date: August 31, 2019
• Field of knowledge: Engineering - Electrical Engineering - Electrical, Magnetic and Electronic Measurements, Instrumentation
• Agreement: SABESP
• Principal Investigator: Fernando Josepetti Fonseca
• Grantee: Vinicius Augusto Machado Nogueira
• Host Institution: Escola Politécnica (EP). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Company: Universidade de São Paulo (USP). Escola Politécnica (EP)
• Associated research grant: 13/50440-7 - Online water quality analysis (ACQUA-OnLine), AP.PITE

Abstract

Organic thin film transistors (OTFTs) are devices composed of three electrodes, similar to MOS devices, with drain (D), source (S) and gate (G). The two main polarization voltages are applied to the drain and the source (VDS and VGS, respectively) in relation to the reference electrode, the source, responsible for generating the characteristic curves of IDSxVDS for a set of VGSe values of IDSx VGS for a set of VDS values. The gate electrode is separated from the conduction channel one by dielectric, and the thickness and the presence of defects in this layer is fundamental to determine the spurious leakage current through the gate, the operating voltages and, even the mobility of cargo carriers. The mobility is a function of physical parameters, such as channel length and width, as well as processing parameters, such as the drying temperature of the active semiconductor layer after deposition coating. In this context, a study is proposed to evaluate the influence of physical parameters and OTFT processing on its electrical parameters. Based on the knowledge acquired in this project, we will look for optimized performance transistors for the creation of an electronic nose whose sensitivity to MIB and GEO reaches 100 parts per billion (ppb).