Bromine Vacancy Redistribution and Metallic‐Ion‐Migration‐Induced Air‐Stable Resistive Switching Behavior in All‐Inorganic Perovskite CsPbBr₃ Film‐Based Memory Device

Abstract

density, fast switching speed, multibit storage potential, and nonvolatile nature, is considered as one of the most promising candidate in nonvolatile memory field. [1][2][3] The RRAM device, with sandwich structure of top metal (TE)/ switching layer/bottom metal (BE), can be switched between a low resistance state (LRS) and high resistance state (HRS) under the stimulation of different voltage amplitudes or polarities. [4] Stable resistive switching (RS) behavior has been observed in various perovskite oxide materials based memory devices, for instances, SrTiO 3 , [5] BaTiO 3 , [6] and BiFeO 3 , [7] etc. However, the perovskite oxide-based RRAM devices are limited by several disadvantages, such as high processing temperature and rigid ceramic property of the switching layer. [8] In recent years, halide perovskites, with formula of ABX 3 (A = CH 3 NH 3+ , CH(NH 2 ) 2+ , Cs + ; B = Pb 2+ , Sn 2+ ; X = Cl − , Br − , I − ), have attracted intensive attention due to their huge potential applications in industrial applications, such as solar cells, [9] photodetectors, [10] light emitting diodes, [11] lasers, [12] and RS memory devices. [13] Many attempts have been focused on this material because of its outstanding properties, for instance, the low exciton binding energy, long-range charge diffusion length, high carrier mobility, high absorption coefficient, and suitable bandgaps. [14][15][16][17] To date, most studies have focused on the organicinorganic hybrid halide perovskites. [16,17] However, despite the demonstrated remarkable performances of the organicinorganic halide perovskites based devices, their industrial applications are limited to the instability, including the poor thermal stability and moisture sensitivity, which is due to the instability nature of the organic cations. [18] Therefore, to obtain air-stable halide perovskites, replacing instable organic cations by stable cations is of great importance. To address this issue, the organic cation is substituted by cesium (Cs) and the ascalled all-inorganic cesium lead halide perovskite (CsPbX 3 ) has attracted a great deal of attention in RS memory field. [19][20][21] All-inorganic halide perovskites have attracted a great deal of attention for applications in resistive switching (RS) memory devices due to their superior stability compared to organic-inorganic hybrid halide perovskites. RS memory devices utilizing air-stable all-inorganic halide perovskite cesium lead bromide (CsPbBr 3 ) film as the switching layer, which are successfully prepared by spin coating at low temperature, are demonstrated. Memory devices based on CsPbBr 3 film exhibit typical reproducible bipolar RS behavior and superior switching characteristics, including the high ON/OFF ratio (≈10 4 ), long data retention (>5 × 10 4 s), and environmental stability. In addition, multilevel storage capability can be achieved through controlling the different compliance currents. The formation and rupture of bromine (Br) vacancy conducting filaments (CFs) is proposed to explain the switching b...

Advances of RRAM Devices: Resistive Switching Mechanisms, Materials and Bionic Synaptic Application

“…After that, some solid electrolyte materials have been presented including Ag 2 Se [24], Ge 2 Sb 2 Te 5 [25], GeTe [124], etc. At present, a series of 2D materials such as graphene [89,125,126], molybdenum disulphide (MoS 2 ) [26,127,128] and perovskite materials (CH 3 NH 3 SnCl 3 and CsPbBr 3 ) [73,90] also inspired researchers' interest due to their small size, ultra-thin thickness and excellent physical properties, which have resulted in superior performance of RRAM devices. Chen et al proposed an electrode/oxide interface engineering technique by inserting single-layer graphene (SLG) into the TiN/HfO 2 /Pt RRAM device [89], which enabled the RESET current to be reduced by 22 times and the programming energy consumption reduced by 47 times.…”

“…( e ) AlO x , reproduced from [ 19 ], with permission from Elsevier, 2020. ( f ) CsPbBr 3 , reproduced from [ 73 ], with permission from John Wiley and Sons, 2019. ( g ) Ge 2 Sb 2 Tr 5 , reproduced from [ 38 ], with permission from John Wiley and Sons, 2019.…”

Light-activated Multilevel Resistive Switching Storage in Pt/Cs2AgBiBr6/ITO/Glass Devices

“…5 c, the doublet peaks of Br 3 and Br 3 signals locate at 69.38 eV and 68.33 eV, respectively. Obviously, they shift toward the positive positions, indicating that V generate in the CABB layer [ 34 ]. In addition, as illustrated in Fig.…”

Resistive Switching Characteristics Improved by Visible-Light Irradiation in a Cs2AgBiBr6-Based Memory Device

“…As shown in Figure 5 a, the Br 3d peak is composed of a doublet with 3d 3/2 and 3d 5/2 signals at 69.38 and 68.33 eV. The Br 3d peaks of the CABB films slightly towards the positive, which indicated that abundant V Brs exists in the CABB film [ 28 ]. Figure 5 b shows the Bi 4f core-level spectrum.…”