Analysis of Performance Diversity in OTFT Utilizing La0.850Nb0.150O4 as Gate Dielectric

Abstract

This paper focuses on depth analysis of different single bottom gate structures; top contact, bottom contact and asymmetrical source and drain contacts for organic thin film transistors (OTFTs). Wherein, performance diversity in terms of drain current is obtained for pentacene based OTFT utilizing La 0.850 Nb 0.150 O 4 as gate dielectric. The Nb (Niobium) inclusion alleviates La (Lanthanum) oxide hygroscopicity and thus making the dielectric surface very smoother, which in turns increases the mobility of the charge carrier. The Atlas-Silvaco device simulator is used for the analysis of performance parameters and electrical characteristics of aforesaid OTFTs. A comparative performance analysis in terms of drain current and threshold voltage is performed for all the proposed Pentacene based OTFT structures. The maximum drain current for top contact, bottom contact, asymmetric contact with drain electrode at OSC layer, asymmetric contact with source electrode at OSC layer at gate voltage of −5 volts and drain voltage of −5 V are 18.67, 0.20, 18.48, and 0.21 µA respectively. The drain current value of the top contact structure and asymmetric contact with drain electrode at OSC layer structure are very close representing resemblance in performance of the two structure.