Stabilization of negative capacitance in ferroelectric capacitors with and without a metal interlayer

Area of Science:

• Materials Science
• Condensed Matter Physics
• Nanotechnology

Background:

• Negative capacitance (NC) in ferroelectric materials is a scientifically intriguing phenomenon.
• NC has potential applications in nanoscale electronic devices, but its existence is debated due to conflicting experimental results.
• Discrepancies arise from experiments on ferroelectric capacitors with and without metal interlayers.

Purpose of the Study:

• To provide a comprehensive analysis of negative capacitance operation in ferroelectric capacitors.
• To offer new insights into the discrepancies observed in experimental studies.
• To investigate the role of interface properties in stable NC operation.

Main Methods:

• Development of theoretical models accounting for the three-dimensional nature of ferroelectric capacitors.
• Comparison of model predictions with experimental data from recent studies.
• Analysis of the influence of traps at the ferroelectric-dielectric interface.

Main Results:

• The developed models show good agreement with several aspects of recent experimental findings.
• The study demonstrates that traps at the ferroelectric-dielectric interface are critical for achieving stable NC.
• The three-dimensional modeling approach helps explain previously contradictory experimental observations.

Conclusions:

• Stable negative capacitance operation in ferroelectric capacitors is feasible and influenced by specific material properties.
• Interface traps significantly impact the stability and observation of negative capacitance.
• This work reconciles experimental discrepancies and advances the understanding of NC for electronic applications.