CF4 plasma treatment of tungsten bottom electrode of Cu/SiOx/W structure for resistive memory applications

• Effects of the CF4 plasma treatment on the resistive switching were studied.
• CF4 plasma treatment deposited fluorine atoms on the tungsten surface.
• CF4 plasma treatment reduced interface thickness and stabilized resistive switching.

The effects of the CF4 plasma treatment on resistive memory devices were investigated. First, a 20-nm SiOx film was deposited on a CF4-treated W/TiN/SiO2/Si substrate using a radio-frequency magnetron sputter, and then a Cu top electrode was deposited to form a Cu/SiOx/CF4-treated W structure. The CF4 plasma treatment deposited fluorine atoms on the tungsten surface, reducing the interface thickness between the SiOx layer and tungsten electrode, and effectively stabilized the resistive switching and improved the switching dispersion. The CF4-treated sample showed good memory properties including a reliable non-volatile memory, non-destructive readout, stable switching voltages, and high resistance ratio of 105.