Graphene oxide charge blocking layer with high K TiO2 nanowire for improved capacitive memory

Glancing angle deposition technique was adopted to fabricate TiO2 nanowire (NW) over spin coated gra-phene oxide (GO) thin-film (TF) for capacitive memory application. The formation of hybrid structure was studied using field emission scanning electron microscope. High accumulation capacitance of 0.994 nF/cm(2) at 7 MHz frequency was obtained for fabricated Au/TiO2 NW/GO TF/Si device as compared to Au/TiO2 NW/Si device (0.4014 nF/cm(2)). A theoretical study using delta depletion model was done, which further validated the relative permeability and flat band voltage of the devices at higher frequency. The memory window of Au/TiO2 NW/Si was found to be 1.36 V at +/- 10 V, which increased to 3.72 V for Au/TiO2 NW/GO TF/Si hybrid device. Also, a large charge storage capacity with good retention (105 s) and endurance (1000 cycles) was observed for the hybrid device. Moreover, Au/TiO2 NW/GO TF/Si device exhibited low leakage current density of 1.6 mu A/cm(2) at +1 V as compared to Au/TiO2 NW/Si device (11.3 mu A/cm(2) at +1 V). The GO TF layer at the bottom increased the potential difference between TiO2 and GO, which acted as a charge trapping layer and thus demonstrated as a good candidate for non-volatile memory application. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

The glancing angle deposition technique was used to fabricate TiO2 nanowires over spin coated graphene oxide thin film for capacitive memory application. The hybrid structure exhibited high accumulation capacitance, increased memory window, and low leakage current density compared to the TiO2 nanowire/Si devices. Overall, the TiO2 nanowire/graphene oxide thin film hybrid device showed promising potential for non-volatile memory applications.