Floating metal layer as top electrode over vertically aligned nanorod arrays using angle deposition technique

Area of Science:

• Materials Science
• Nanotechnology
• Electrical Engineering

Background:

• Vertically aligned nanorod arrays (NRAs) are crucial for advanced electronic devices.
• Fabricating uniform floating metal layers (FMLs) on NRAs presents significant challenges.
• Existing deposition methods often lack the precision required for complex nanostructures.

Purpose of the Study:

• To develop a new angle deposition technique (ADT) for creating FMLs on NRAs.
• To investigate the resistive switching properties of devices fabricated using ADT.
• To understand the influence of deposition parameters on FML formation and device performance.

Main Methods:

• Utilized a novel ADT with two simultaneous metal sources to deposit copper (Cu) onto titanium dioxide (TiO2) NRAs.
• Employed computational estimation to model the FML formation based on NRA dimensions and source parameters.
• Fabricated Cu/TiO2-NRA/FTO vertical devices on fluorine-doped tin oxide (FTO) coated glass.
• Performed current-voltage (I-V) characteristic measurements to analyze resistive switching behavior.

Main Results:

• Successfully realized a uniform FML over TiO2-NRAs using the developed ADT.
• Observed distinct resistive switching behavior in the Cu/TiO2-NRA/FTO devices.
• Demonstrated a transition from high to low resistance state during positive voltage sweeps and negative differential resistance during negative sweeps.

Conclusions:

• The novel ADT is effective for fabricating FMLs on NRAs, enabling the creation of resistive switching devices.
• The study provides insights into controlling FML characteristics through deposition parameters.
• The demonstrated resistive switching behavior highlights the potential of these devices for memory and logic applications.