Self-rectifying resistance switching memory based on a dynamic p-n junction

Area of Science:

• Materials Science
• Solid-State Electronics
• Semiconductor Devices

Background:

• Resistance Random Access Memory (RRAM) is a promising next-generation memory technology.
• High-density RRAM crossbar arrays face challenges due to sneak-path currents.
• Integrating rectifying effects with resistance switching is a potential solution.

Purpose of the Study:

• To develop a self-rectifying resistance switching (SR-RS) device to suppress sneak-path currents.
• To investigate a novel Li-ion migration-induced dynamic p-n junction for memory applications.
• To assess the feasibility of the proposed structure for high-density RRAM.

Main Methods:

• Fabrication of an Au/Li-ZnO/ZnO/Pt device structure.
• Characterization of resistance switching and rectification properties.
• Analysis of the dynamic p-n junction formation mechanism via Li-ion migration and defect complex dynamics.

Main Results:

• The SR-RS device demonstrated forming-free and stable switching with a high resistance ratio (R_OFF/R_ON ~ 10^4).
• A large rectification ratio of approximately 10^6 was achieved.
• The Li-ZnO/ZnO bilayer facilitated a dynamic p-n junction by electric-field-driven Li-ion transport and defect complex recombination.

Conclusions:

• The proposed SR-RS device effectively suppresses sneak-path currents, enabling selection-device-free operation.
• The dynamic p-n junction mechanism provides a viable route for high-density RRAM.
• The structure shows potential for realizing high-density RRAM applications, with a calculated maximum array size of ~16 Mbit.