Breaking the Trade‐Off Between Polymer Dielectric Constant and Loss via Aluminum Oxo Macrocycle Dopants for High‐Performance Neuromorphic Electronics

Abstract

AbstractThe dielectric layer is crucial in regulating the overall performance of field‐effect transistors (FETs), the key component in central processing units, sensors, and displays. Despite considerable efforts being devoted to developing high‐permittivity (k) dielectrics, limited progress is made due to the inherent trade‐off between dielectric constant and loss. Here, a solution is presented by designing a monodispersed disk‐shaped Ce–Al–O‐macrocycle as a dopant in polymer dielectrics. The molecule features a central Ce(III) core connected with eight Al atoms through sixteen bridging hydroxyls and eight 3‐aminophenyl peripheries. The incorporation of this macrocycle in polymer dielectrics results in an up to sevenfold increase in dielectric constants and up to 89% reduction in dielectric loss at low frequencies. Moreover, the leakage‐current densities decrease, and the breakdown strengths are improved by 63%. Relying on the above merits, FETs bearing cluster‐doped polymer dielectrics give near three‐orders source‐drain current increments while maintaining low‐level leakage/off currents, resulting in much higher charge‐carrier mobilities (up to 2.45 cm2 V−1 s−1) and on/off ratios. This cluster‐doping strategy is generalizable and shows great promise for ultralow‐power photoelectric synapses and neuromorphic retinas. This work successfully breaks the trade‐off between dielectric constant and loss and offers a unique design for polymer composite dielectrics.