Effects of rubidium substitution of Cs2−xRbxAgBiBr6 double halide perovskites on resistive switching characteristics for memory applications.

Cation substitution technique in halide perovskites (HPs) is one of the famous schemes to enhance the characteristics of HPs-based electronic and optoelectronic devices. Here, we fabricated rubidium (Rb) substituted inorganic double halide perovskites (HPs) Cs 2−x Rb x AgBiBr 6 (x = 0, 0.05, 0.1, 0.2, and 0.3) film-based resistive switching (RS) devices and investigated effects of Rb cation substitution on characteristics of RS devices. Grain sizes of the formed Cs 2−x Rb x AgBiBr 6 films gradually increased as increase of Rb contents in the precursor. All of the fabricated RS devices demonstrated non-volatile bipolar RS behavior, device with the Rb content x = 0.1 showed a particularly high on/off ratio (9.29 × 102) of about 30 times greater than pristine Cs 2 AgBiBr 6 -based ones (3.09 × 10). In addition, it has been shown that an appropriate amount of Rb substitution at the level of x = 0.1 can effectively prevent the appearance of other crystalline phases at high humidity condition of > 80 %. Through various analytical techniques including SEM, XPS, and SCLC measurement, it was confirmed that an enlargement in grain size resulting in a decrease in defects such as Br vacancies in the fabricated film can lead to an increase in resistance at a high resistance state (HRS) and high on/off resistance ratio. This study provides a facile and feasible way to enhance performances of HPs-based RS devices for practical electronic memory applications. [Display omitted] • We fabricated rubidium (Rb) substituted inorganic double halide perovskites (HPs) Cs 2−x Rb x AgBiBr 6 film-based resistive switching (RS) devices • Grain sizes of Cs 2−x Rb x AgBiBr 6 (x = 0, 0.05, 0.1, 0.2, and 0.3) films gradually increased as increase of Rb contents. • Cs 2−x Rb x AgBiBr 6 -based RS devices with x = 0.1 showed a particularly high on/off ratio (9.29 × 102) of about 30 times greater than pristine one. • An appropriate amount of Rb substitution at the level of x = 0.1 can prevent the appearance of other phases at high humidity condition of > 80 %. [ABSTRACT FROM AUTHOR]