TiO _x -based self-rectifying memory device for crossbar WORM memory array applications*

Abstract

Resistive switching with a self-rectifying feature is one of the most effective solutions to overcome the crosstalk issue in a crossbar array. In this paper, a memory device based on Pt/TiO x /W structure with self-rectifying property is demonstrated for write-once-read-many-times (WORM) memory application. After programming, the devices exhibit excellent uniformity and keep in the low resistance state (LRS) permanently with a rectification ratio as high as 104 at ± 1 V. The self-rectifying resistive switching behavior can be attributed to the Ohmic contact at TiO x /W interface and the Schottky contact at Pt/TiO x interface. The results in this paper demonstrate the potential application of TiO x -based WORM memory device in crossbar arrays.

The Effect of Nitrogen Annealing on the Resistive Switching Characteristics of the W/TiO2/FTO Memory Device

“…Figure 4 b indicates the retention tests of the device at the reading voltage of 0.1 V after the rapid nitrogen annealing treatment, it is appreciable that the R HRS /R LRS of the W/TiO 2 /FTO memory device increased from about two orders of magnitude to three orders of magnitude after the rapid nitrogen annealing treatment. In comparison with the previous reports about TiO 2 memory devices as summarized in Table 1 [ 16 , 17 , 18 , 19 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 31 ], the W/TiO 2 /FTO memory device in this work has a relatively lower V set and the highest resistance ratio of about three orders of magnitude, which demonstrates the outstanding potential of the W/TiO 2 /FTO memory device for the future nonvolatile memory applications.…”

“…Moreover, another important factor affecting the performances of the memristors is the preparation process. The transition metal oxide TiO 2 has been prepared by the hydrothermal method [ 16 , 17 , 18 , 19 , 20 ], the magnetron sputtering method [ 21 , 22 ], the electrochemical anodization method [ 23 , 24 ], the atomic layer deposition method (ALD) [ 25 , 26 ], and other methods [ 27 , 28 , 29 ]. In particular, the hydrothermal method with its simple experimental steps and high economic benefits is an effective approach to prepare the transition metal oxide TiO 2 .…”