Rational Modification of Small Molecules with High Device Reproducibility Induced by Improved Interfacial Contact through Intermolecular Hydrogen Bonds

The interfacial contact between the semiconductor and the electrode can effectively affect the device performance through the penetration of metal atoms in semiconductors from the grain boundaries. Thus, how to design a novel molecule with few grain boundaries, namely, large grain size, in solid state is an important task to achieve excellent memory device with high reproducibility. Intermolecular hydrogen-bonding interaction has been proved to be a powerful driving force for molecules assembling into large crystalline aggregates. In this work, the molecular terminals with different numbers of electron-deficient imine (C═N) nitrogen atoms are designed to investigate the effect of hydrogen-bonding interaction on molecular crystalline grains and interfacial contact. X-ray diffraction and grazing-incidence small-angle X-ray scattering measurements verified the superior molecular aggregates and grain boundaries of the molecule with two hydrogen-bonding sites in solid state, donating the corresponding devices showing optimized ternary data-storage performance with lower threshold voltages and higher device reproducibility.