Performance evaluation of top contact PANI organic thin film transistors with SiO2 and poly(methyl methacrylate) as gate dielectrics

Organic thin film transistors (OTFTs) were fabricated using polyaniline (PANI) of 3wt.% concentration, as the active layer with two different gate dielectrics, namely silicon dioxide (SiO2) and poly(methyl methacrylate) (PMMA), in top contact geometry for comparative studies. To deal with poor stability and large leakage currents between source/drain and gate electrodes, isolated OTFTs with reduced source/drain contact area were fabricated by selective deposition of PANI on SiO2 through shadow mask. The effects of the PMMA thickness on the performance of OTFTs has been investigated. The results analysis of the PMMA-based OTFTs exhibited encouraging performance because of their good dielectric characteristics as compared to SiO2.