Observation of Resistive Switching Memory by Reducing Device Size in a New Cr/CrO x /TiO x /TiN Structure

Abstract

The resistive switching memory characteristics of 100 randomly measured devices were observed by reducing device size in a Cr/CrOx/TiOx/TiN structure for the first time. Transmission electron microscope image confirmed a via-hole size of 0.4 µm. A 3-nm-thick amorphous TiOx with 4-nm-thick polycrystalline CrOx layer was observed. A small 0.4-µm device shows reversible resistive switching at a current compliance of 300 µA as compared to other larger size devices (1–8 µm) owing to reduction of leakage current through the TiOx layer. Good device-to-device uniformity with a yield of >85 % has been clarified by weibull distribution owing to higher slope/shape factor. The switching mechanism is based on oxygen vacancy migration from the CrOx layer and filament formation/rupture in the TiOx layer. Long read pulse endurance of >105 cycles, good data retention of 6 h, and a program/erase speed of 1 µs pulse width have been obtained.

Resistive Switching Memory of TiO2 Nanowire Networks Grown on Ti Foil by a Single Hydrothermal Method

“…Compared to TiO 2 thin films used for ReRAM [ 6 , 19 – 22 ], few studies based on one-dimensional TiO 2 nanomaterials for ReRAM have been reported. It was recently shown that a single TiO 2 nanowire-based resistive switching device demonstrated multilevel memory behavior [ 23 , 24 ].…”

Temperature-Dependent Non-linear Resistive Switching Characteristics and Mechanism Using a New W/WO3/WOx/W Structure

“…Although different switching materials such as Ta 2 O 5 [5–7], HfO 2 [8, 9], TiO 2 [10–12], and Al 2 O 3 [13–15] have been reported, however, only a few studies have been reported on WO 3 material [16, 17]. WO 3 has an acceptable energy gap of 3.25 eV [18] and Gibbs free energy of approximately −529 kJ/mol at 300 K [19].…”

“…Recently, resistive random access memory (RRAM) has become a promising candidate to replace three-dimensional FLASH for crossbar applications at a low cost owing to its simple structure, low power consumption, and high-speed operation [ 1 – 4 ]. Although different switching materials such as Ta 2 O 5 [ 5 – 7 ], HfO 2 [ 8 , 9 ], TiO 2 [ 10 – 12 ], and Al 2 O 3 [ 13 – 15 ] have been reported, however, only a few studies have been reported on WO 3 material [ 16 , 17 ]. WO 3 has an acceptable energy gap of 3.25 eV [ 18 ] and Gibbs free energy of approximately −529 kJ/mol at 300 K [ 19 ].…”

Retention Model of TaO/HfO x and TaO/AlO x RRAM with Self-Rectifying Switch Characteristics

“…Those oxygen vacancies are recombined during the negative biasing reset process. Unlike filamentary-type RRAM, the HRS is always lower than the initial resistance state (IRS) after a reset operation [ 15 – 17 ]. To summarize, defect-trapping is a process that modulates vacancies through oxygen ion–vacancy recombination to control the resistance variation in the switching layer.…”