Stability of PMMA on P3HT PTFTs under stress

In this paper we study the stability under stress of polymeric thin film transistors, PTFTs, fabricated with poly(methyl methacrylate) PMMA on poly(3-hexylthiophene) P3HT as dielectric and semiconductor layers, respectively. Devices were tested during and after gate bias stress combined with drain bias. When the stress is done at low drain bias, VT shift in linear transfer curves remained below 1 V. When both high gate and drain bias are applied during stress, linear transfer curves shifted less than 5 V. In both cases hysteresis was less than 1 V. Transfer curves for VDS = −30 V after stress showed deformation in addition to shift. Variation of IDS at VDS = −30 V during both types of stress remained always below 6%. Mechanisms responsible for the observed behavior are discussed.