Pentacene organic thin-film transistor based on Archimedean interdigitated spiral pattern

In this paper we describe the design, fabrication and technology for organic transistor OTFTs, in view of investigation of its I-V characteristic and capacitance. OTFTs are arising as emerging components for novel electric switches in digital circuits, inverter and primary power electronics components of PV systems. Moreover, they are emerging also in the explosive development of grid-connected markets, providing cost reductions and increasing efficiency. Specifically, here we analyze OTFTs whose pattern is based on two archimedean spirals. The novel aspect of this work is that the source/drain contacts are characterized by an Archimedean spiral shape, as opposed to the traditional rectangular shape. Main contributions of this work are: (i) the output characteristic curves of the OTFTs, (ii) the measurement of the capacitance of the entire device together with its analytical estimate and (iii) the validation through AFM that the geometry of the layers is coherent with that set during the fabrication of the OTFT.