Threshold Switching Behavior and Underlying Mechanisms in Pure SiO₂-Based Selectors.

Area of Science:

• Materials Science
• Electrical Engineering
• Semiconductor Physics

Background:

• Selector devices are vital for suppressing sneak-path currents in high-density crossbar array memory.
• Conventional selectors often rely on complex materials like chalcogenides or metal oxides.

Purpose of the Study:

• To propose and demonstrate a pure silicon dioxide (SiO2)-based selector for crossbar memory applications.
• To elucidate the fundamental mechanisms behind the threshold switching behavior in SiO2 selectors.

Main Methods:

• Fabrication of SiO2 selectors using conventional semiconductor processes.
• Experimental characterization of threshold switching (TS) behavior, including endurance testing.
• Interface structure analysis and controlled pulse-based electrical characterization.

Main Results:

• Demonstrated stable TS characteristics with endurance exceeding 10^9 cycles.
• Identified oxygen vacancy formation, structural asymmetry, and dynamic charging as key TS mechanisms.
• Optimized pulse conditions for reliable TS operation were established.

Conclusions:

• The pure SiO2 selector offers a simple, CMOS-compatible alternative to conventional selectors.
• Low-temperature fabrication (<300 °C) and tunable threshold voltage enable excellent integration with advanced memory devices.
• This work presents a promising pathway for highly integrated, silicon-compatible memory selectors.