Ambipolar organic electronics have been gaining interest as a simple alternative technology for implementing complementary-like circuits. Although practical applications require stable operation in the air, most previous studies on ambipolar organic electronics have reported results measured in high vacuum or N₂ atmosphere only. This is because ambipolar properties change to asymmetric p-type dominant or unipolar p-type characteristics when exposed to air. Little effort has been put into the fundamental investigation of the effects of the environmental atmosphere on ambipolar organic semiconductors. In this paper, we demonstrate ambipolar OTFTs with balanced p/n characteristics under ambient air using poly{[N,N′-bis(3-decylpentadecyl)-naphtho[2,3-b:6,7-b′]dithiophene-4,5,9,10-tetracarboxidiimide-2,7-diyl]-alt-5,5′-(2,2′-bithiophene)} (PNDTI-BT-DP). Based on the analysis using XPS, UPS, and electrical characterizations at various atmosphere, we concluded that the PNDTI-BT-DP has 0.45 eV higher than the target value for ambiplar charge injections with respect to Au contact electrode. The energy level of the PNDTI-BT-DP was up-shifted by 0.45 eV when the film was exposed to ambient air, which resulted in a change in the electrical properties. As a proof-of-concept application, we demonstrate the air-stable split-gate OTFTs that operate as either a unipolar p- or n-type device based on electrical control. Finally, we report results showing that the device characteristics for both p- or n-type operations were maintained after ∼120 h of atmospheric exposure.

作为用于实现类互补电路的简单替代技术，双极性有机电子器件已引起人们的兴趣。尽管实际应用需要在空气中稳定运行，但是大多数先前关于双极性有机电子的研究都报告了仅在高真空或N ₂气氛下测量的结果。这是因为当暴露于空气时，双极性特性变为不对称的p型主导或单极性p型特性。对于基本环境研究对双极性有机半导体的影响，人们几乎没有做出任何努力。在本文中，我们使用聚{[ N，N'-双（3-癸基十五烷基）-萘[2,3-b：6,7- b '] dithiophene-4,5,9,10-tetracarboxidiimide-2,7-diyl] -alt-5,5'-（2,2'-联噻吩）}（PNDTI-BT-DP）。基于使用XPS，UPS进行的分析以及在各种气氛下的电特性，我们得出的结论是，PNDTI-BT-DP相对于Au接触电极的双电荷注入目标值比目标值高0.45 eV。当薄膜暴露于环境空气中时，PNDTI-BT-DP的能级上移0.45 eV，这导致电性能发生变化。作为概念验证的应用，我们演示了基于电气控制的，可作为单极性p型或n型器件运行的空气稳定型分离栅OTFT。最后，我们报告的结果表明，p型或n型操作的器件特性在约120小时的大气暴露后都得以保持。