Microscopic Investigation of the Electrical and Structural Properties of Conductive Filaments Formed in Pt/NiO/Pt Resistive Switching Cells

作者：Iwata Tatsuya^*; Nishi Yusuke; Kimoto Tsunenobu

来源：Japanese Journal of Applied Physics, 2013, 52(4): 041801.

DOI：10.7567/JJAP.52.041801

Conductive filaments formed in Pt/NiO/Pt resistive switching (RS) cells were characterized by conductive atomic force microscopy (C-AFM) and cross-sectional transmission electron microscopy (XTEM) after the removal of top electrodes. The area and current of the filaments were directly detected by C-AFM. By examining various RS cells with different cell resistances in the low-resistance state (R-LRS), it has been revealed that the R-LRS variation in the range of 10-220 delta is mainly caused by the variations in the area and shape of the filaments. XTEM was carried out on a filament that dominantly determines R-LRS. The area of the filament significantly varied along the thickness direction of a NiO film, which was consistent with the speculation from C-AFM analysis. Furthermore, the filaments observed in this study consist of reduced NiO with an inclusion of platinum, the electrode material, owing to Joule heating by the current during forming.

• 出版日期2013-4