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engineering advancements are speeding up the development of electrolyte materials with lower activation energy barriers and channel materials with lower redox energy barriers. [1a,4] Proton based ECRAM (H-ECRAM) is potentially advantageous because proton (H + ) is a smaller and more rapidly diffusing ion than Li + and O 2− . However, the memory state-retention times of H-ECRAM far remained relatively short with cycling instability. [5] Due to H-ECRAM poor memory state-retention, inference accuracy degrades over time. The poor retention in H-ECRAM is caused by self-discharge of intercalated ions from the channel layer due to existence of non-zero open circuit potential (OCP), which is mainly occurred in polymer-based H-ECRAM. [6] When the gate circuit opens during the read operation, the electrically conductive electrolyte is unable to halt the backflow of electrons, resulting in non-zero OCP and subsequent self-discharge of H + ions. Fuller et al. connected a selector in series with the H-ECRAM gate terminal to address the OCP issue, forming a one-selector-one-H-ECRAM (1S1E) structure that isolates the device and prevents leakage current. [7] In our opinion, the memory state-retention and cycling stability of H-ECRAM can be improved by developing proton-conducting solid electrolytes with electron-blocking properties to lower the self-discharge issue. However, the unavailability of a CMOS-compatible proton-conducting solid electrolyte is the main obstacle. All H-ECRAM presently relied on electrolytes that either cannot be integrated and scale down, such as polymer, [8] ionic liquid, [9] ionic gel, [10] organic material. [5] Herein, atomically thin single-layer hexagonal boron nitride (hBN) is integrated into H-ECRAM as a proton-conducting solid-state electrolyte. Atomically thin 2D material has not yet been exploited in prior research for the purpose of improving memory state-retention and cycling stability of ECRAM devices. Recent research has proven that a few 2D materials exhibit ion transport properties both experimentally and theoretically. [11] Hexagonal boron nitride (hBN) single-layers have been evaluated as a possible material for developing novel ionic transport layers. [12] The honeycomb structure of 2D h-BN is composed of alternating boron and nitrogen atoms. [13] It exhibits superior chemical and thermal stability, as well as mechanical strength. [14] ProtonThe first report on ion transport through atomic sieves of atomically thin 2D material is provided to solve critical limitations of electrochemical randomaccess memory (ECRAM) devices. Conventional ECRAMs have random and localized ion migration paths; as a result, the analog switching efficiency is inadequate to perform in-memory logic operations. Herein ion transport path scaled down to the one-atom-thick (≈0.33 nm) hexagonal boron nitride (hBN), and the ionic transport area is confined to a small pore (≈0.3 nm 2 ) at the single-hexagonal ring. One-atom-thick hBN has ion-permeable pores at the center of each hexagonal ring due to weakened elect...

The formation of an interfacial layer is believed to affect the ferroelectric properties in HfO2 based ferroelectric devices. The atomic layer deposited devices continue suffering from a poor bottom interfacial condition, since the formation of bottom interface is severely affected by atomic layer deposition and annealing process. Herein, the formation of bottom interfacial layer was controlled through deposition of different bottom electrodes (BE) in device structure W/HZO/BE. The transmission electron microscopy (TEM) and x-ray photoelectron spectroscopy analyses done on devices W/HZO/W and W/HZO/IrO x suggest the strong effect of IrO x in controlling bottom interfacial layer formation while W/HZO/W badly suffers from interfacial layer formation. W/HZO/IrO x devices show high remnant polarization (2P r) ∼ 53 μC cm−2, wake-up free endurance cycling characteristics, low leakage current with demonstration of low annealing temperature requirement as low as 350 °C, valuable for back-end-of-line integration. Further, sub-5 nm HZO thicknesses-based W/HZO/IrO x devices demonstrate high 2P r and wake-up free ferroelectric characteristics, which can be promising for low power and high-density memory applications. 2.2 nm, 3 nm, and 4 nm HZO based W/HZO/IrO x devices show 2P r values 13.54, 22.4, 38.23 μC cm−2 at 4 MV cm−1 and 19.96, 30.17, 48.34 μC cm−2 at 5 MV cm−1, respectively, with demonstration of wake-up free ferroelectric characteristics.

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Engineering of HfO 2 −ZrO 2 ferroelectric thin films can substantially increase their dielectric constant. Here, we investigate dielectric and structural properties of ∼10 nm thin films consisting of stacked 1 nm thin ferroelectric (FE) Hf 1−x Zr x O 2 (HZO(x)) and antiferroelectric (AFE) ZrO 2 layers. At x < 0.5, the measurements of polarization vs electric field revealed pure FE hysteresis loops, whereas at x > 0.5, pinched hysteresis loops with some remnant polarization were observed, which indicate a coexistence of FE and AFE orderings. Finally, a pure ZrO 2 thin film (x = 1) exhibits only an AFE double hysteresis loop. In this way, we demonstrate that the coexistence of FE and AFE orderings can be controlled by adjusting the composition of HZO(x) layers in the HZO(x)/ZrO 2 nanolaminate films. At x = 0.5, the dielectric constant is ∼60 in nanolaminate films, which is much higher than that of the conventional HZO(x) solid solution thin films. Structural investigations confirm a coexistence of polar orthorhombic and nonpolar tetragonal structures, which is consistent with the observed polarization hysteresis loops. We also show that the strain generated in the nanolaminate structure significantly facilitates a field-induced transition from the AFE to the FE phase. The design does not considerably affect the leakage current in HZO(x)/ZrO 2 nanolaminate films, which makes this system highly promising for complementary metal oxide semiconductor-compatible capacitors.