Design and Analysis of Low Voltage High Mobility OFETs by Using High-K Dielectrics or by Varying Thickness of Dielectric

Abstract

OFETs (Organic Field-Effect Transistors) are known for its low cost, flexibility, light weight and availability of plenty of organic compounds which makes them a perfect choice for electronic applications. However, stability issues are still a concern in OFETs which limits their efficiency. Also, to be able to employ OFETs for low power consumption devices, their operating voltage should be reduced. To fulfil this requirement, low values of transistor threshold voltage (V_T) and subthreshold swing (SS) are essential. This is a very challenging task as it requires either the gate dielectric thickness to be reduced or by using high-k dielectrics [1]. In this paper, a p-type OFET with DPP (Diketopyrrolopyrrole) as p-type semiconductor [2], SiO₂ as dielectric, Gold as Source and Drain regions is designed and various parameters are extracted like threshold voltage, subthreshold swing, I_ON/I_OFF, mobility etc. Gate voltage of OFETs is then reduced by varying the thickness of dielectric (SiO₂) and also by varying dielectrics (SiO₂, ZrO₂, TiO₂).