Thermoelectric Seebeck effect in oxide-based resistive switching memory.

Area of Science:

• Materials Science
• Condensed Matter Physics
• Nanotechnology

Background:

• Oxide-based resistive switching memory utilizes electric-field-induced reversible changes in resistance.
• Conductive filaments are believed to form and rupture during resistive switching, but their transport properties are poorly understood.
• Direct characterization of conductive filament properties is challenging.

Purpose of the Study:

• To investigate the intrinsic electronic transport mechanism within conductive filaments in resistive switching memory.
• To elucidate the role of electron transport in different resistance states.
• To establish a fundamental framework for modeling resistive switching behavior.

Main Methods:

• Measurement of thermoelectric Seebeck effects to probe electronic transport.
• Analysis of temperature-dependent resistance to understand transport mechanisms.
• Investigation across various resistance states of the memory device.

Main Results:

• The small-polaron hopping model successfully describes electronic transport in all resistance states.
• Observed a distinct semiconductor-metal transition around 150 K in low resistance states.
• Temperature-dependent resistance behaviors were found to be contrary across different states, yet explained by the hopping model.

Conclusions:

• Small-polaron hopping is the dominant electronic transport mechanism in the conductive filaments.
• The observed semiconductor-metal transition provides crucial insights into the nature of low-resistance states.
• This work offers a foundational understanding for modeling resistive switching phenomena in oxide-based memory devices.