Interface engineering for improving reliability of resistance switching in Cu/HfO2/TiO2/Pt structure

Abstract

Reliability and uniformity in resistance switching behaviours in top electrode Cu-sputtered TiO2-bottom electrode Pt memory structure were greatly improved by inserting an interface layer of 5 nm-thick HfO2 between Cu and 50 nm-thick TiO2. The thin HfO2 layer, with much smaller cluster size than TiO2, limited the Cu migration appropriately and induced more uniform Cu conducting filament distribution. The repeated rejuvenation and rupture of Cu filament was limited within the HfO2 layer, thereby improving the switching reliability and uniformity. This also greatly decreased operation power compared to a memory cell without the thin HfO2 layer.

Multilevel programming in Cu/NiOy/NiOx/Pt unipolar resistive switching devices

“…Recently, miniaturization has been making it difficult for memory device fabrication technology to achieve high-density data storage. In order to overcome this, resistive random access memory (RRAM) devices are now emerging as some of the most promising candidates for next-generation memory applications [11,13,14,18,26,35,38]-though there exist several models for understanding the underlying mechanism [1,4,15,19,37]. Electrochemical-metallization-(ECM)based resistive switching (RS) [6,7,18,22,34,35] is considered to be the strongest contender, due to its easy backend-of-the-line (BEOL) processability with conventional CMOS technology using Cu as the active electrode [35].…”

Enhancement of data storage capability in a bilayer oxide-based memristor for wearable electronic applications

“…Therefore, it appears that the creation and annihilation of the percolation path made of Cu filament is the origin of the RS mechanism in the ZnO/NiO film. It is further believed that unlike the single-layer device, the ZnO layer acts as a buffer layer of Cu, and the NiO layer ultimately plays the role of a switching layer [2,3,21]. Moreover, the smaller dispersion in V SET and V RESET of the ZnO/NiO heterostructured devices indicated the uniform and controlled formation and rupture process of the CFs.…”

“…Resistive random access memory (RRAM) is considered one of the candidates with the most potential for next-generation non-volatile memory devices due to its low power consumption, rapid switching speed and high-density data storage [1][2][3][4][5]. Normally, the RRAM possesses metal/insulator/metal (MIM) structure, where the insulator acts as an active layer [4,5].…”

“…Among different TMO materials, ZnO and NiO have suitable advantages due to their proper switching, enhanced reversibility and high ON/OFF ratio [3,14,16]. Although the RS mechanism of these materials has already been studied, an in-depth investigation is obligatory to improve the consistency of the switching parameters, such as switching voltage, endurance, data retention properties, etc [2,5,6]. In addition, there is fastidious research interest to make a multilevel memory cell (MLC) due to the increasing demands of high-density data storage [3,4].…”

Recent advances in emerging neuromorphic computing and perception devices

“…Similar to CBRAM, the conductance adjustment of filamentary RRAM is achieved through the soft breakdown of the dielectric layer and the CFs formed by oxygen vacancies [61][62][63][64][65]. The typical structure of the device is shown in figure 2(c), which is a metal-insulator-metal structure.…”