Synthesis of Amorphous‐Crystalline Mixture Boron Nitride for Balanced Resistive Switching Operation

Abstract Two‐dimensional boron nitride (BN) insulating layers gained attracted attention for their high‐performance memristive behavior. However, crystalline hexagonal BN (h‐BN) suffers from a high initial SET voltage due to a lack of boron vacancies, while vacancy‐rich amorphous BN (a‐BN) exhibits significant current fluctuations during RESET due to stochastically formed filaments. In this work, an amorphous‐crystalline mixture BN (acm‐BN) via low‐pressure chemical vapor deposition to achieve balanced resistive switching, offering low SET voltage and improved RESET stability is synthesized. High‐resolution transmission electron microscopy reveals that BN films grown at 930 °C are predominantly amorphous, with crystalline phases increasing at higher temperatures, resulting in homogeneous crystalline areas with partial amorphous regions at 990 °C. This structure in acm‐BN allows low‐voltage filament formation through the localized a‐BN regions during the SET process and sharp rupture of the confined filament during the RESET process. Consequently, acm‐BN exhibits a lower breakdown voltage (3–5 V) during the initial SET cycle compared to h‐BN (9.2 V) and stable RESET cycles and long retention times exceeding 10 000 s, while a‐BN exhibits significant fluctuations and short retention. Furthermore, acm‐BN exhibits better long‐term potentiation linearity (non‐linearity factor β = 1.4), enabling higher learning efficiency (87.26%) compared to a‐BN (β = 4.8, 63.86%).