Performance Investigation of Pentacene Based Organic Double Gate Field Effect Transistor and its Application as an Ultrasensitive Biosensor

In this paper, the electrical performance of double gate organic field effecttransistor (DG-OFET) are thoroughly investigated and feasibility of the deviceas an efficient biosensor is comprehensively assessed. The introduced deviceprovides better gate control over the channel, yielding better charge injectionproperties from source to channel and providing higher on-state current incomparison with single gate devices. The susceptibility of fundamental electricalparameters with respect to the variation of design parameters is thoroughlycalculated. In particular, standard deviation and average value of main electricalparameters signify that metal gate work function, channel thickness and gateoxide thickness are fundamental design measures that may modify the deviceefficiency. The insensitivity of off-state current to the change of channel lengthand drain bias confirms feasibility of the device in the nanoscale regime. Next,a nano cavity is embedded in the gate insulator region for accumulation ofbiomolecules. The immobilization of molecules with different dielectric constantsin the gate insulator hollow alters the gate capacitance and results in the draincurrent deviation with respect to the air- filled cavity condition. It is shown thatby the occupancy of the whole volume of the nanogap, a maximum range of onstatecurrent variation can be achieved.