Organic–inorganic hybrid dielectrics are gaining attention for their potential to improve both the dielectric constant (k) and mechanical flexibility in gate dielectric layers for flexible and wearable electronics. Traditional solution-based hybrid materials face challenges in maintaining high dielectric quality when scaled down in thickness. To address this, our study introduces a novel vapor-phase synthesis method for creating ultrathin, homogeneous, high-k organic–inorganic hybrid dielectrics. Using initiated chemical vapor deposition (iCVD), we synthesized a series of hybrid dielectrics with 2-hydroxyethyl methacrylate and trimethylaluminum. This method allows precise control over thickness and composition, resulting in uniform, defect-free hybrid dielectrics. These dielectrics boast a high-k value of 7 and a low leakage current density of less than 3 × 10–7 A/cm² at 2 MV/cm, even with an equivalent oxide thickness under 5 nm. The dielectric layer also shows outstanding chemical stability, smooth surface morphology, and maintains its performance under tensile strain up to 2.6%. Organic thin-film transistors utilizing these hybrid dielectrics as the gate dielectric demonstrate hysteresis-free transfer characteristics and excellent mechanical flexibility with an operating voltage up to 4 V. This innovative iCVD process positions these hybrid dielectrics as promising candidates for high-performance, low-power flexible electronics. – Journal cover design by scapiens

https://pubs.acs.org/doi/10.1021/acsami.8b12716