New Synthetic Routes to Next-Generation Organic P-Type Dopants for Improved Stretchable Transistors

Intrinsically stretchable electronics have significant promise in revolutionizing bioelectronic health interfaces and wearable consumer electronics due to viscoelastic matching with biological tissue. Despite the development of highly scalable process flows for the production of intrinsically stretchable electronics that yield devices with high transistor density, the operating gate voltages reside between ∼30-60 V, well outside consumer/commercially applicable regimes of ∼1-5 V. Previously, thiol-ene crosslinking chemistry was shown to initiate favorable dielectric behavior in stretchable semiconductors and reduce gate voltage to commercially applicable regimes, but currently thiol-ene chemistry is not compatible with the azide-mediated crosslinking employed for the stretchable dielectric in highly scalable process flows for intrinsically stretchable electronics. The design of a new p-type dopant for stretchable diketopyrrolepyrrole (DPP) semiconductors that also incorporates thiol-ene reactive moieties, would thus be compatible with azide-mediated processing and enable high transistor density and scalability for the next-generation improvements in stretchable transistors. Therefore, this thesis proposes four new synthetic routes for new organic p-type dopants, generates a novel contribution to the literature - oxidized allyl-F4TCNQ - that incorporates thiol-ene reactive moieties, and successfully dopes a DPP-type material (DPP-SVS) by an increase in output current of a DPP-type polymer by ∼3 orders of magnitude. Synthetic considerations and insights gained from the novel production of oxidized allyl-F4TCNQ in this thesis thus function as an important starting material to propose improved synthetic routes for next-generation organic p-type dopants in stretchable transistors.