Electromagnetic energy harvesting based on HfZrO tunneling junctions

Area of Science:

• Solid State Physics
• Materials Science
• Nanotechnology

Background:

• Ferroelectric materials are crucial for advanced electronic devices.
• Hafnium zirconate (HfZrO) thin films offer tunable properties for novel applications.
• Efficient energy harvesting is essential for the Internet of Things (IoT).

Purpose of the Study:

• To fabricate and characterize 6 nm HfZrO ferroelectric tunneling diodes on silicon.
• To investigate the rectifying behavior and energy harvesting capabilities of these diodes.
• To assess the potential of HfZrO diodes for harvesting 26 GHz electromagnetic energy.

Main Methods:

• Atomic layer deposition (ALD) for growing 6 nm HfZrO films on Si.
• Electron-beam metallization for depositing top and bottom electrodes.
• Current-voltage (I-V) measurements to analyze rectifying behavior and ON-OFF ratio.
• Coupling diodes with an antenna array to measure electromagnetic energy harvesting at 26 GHz.

Main Results:

• Fabricated HfZrO tunneling diodes exhibit a significant rectifying behavior with an ON-OFF ratio of approximately 10^4.
• The diodes demonstrate efficient harvesting of 26 GHz electromagnetic energy, with currents at the mA level.
• Achieved responsivity of 63 V W^-1 and Noise Equivalent Power (NEP) of 4 nW/Hz^0.5 for energy harvesting.

Conclusions:

• 6 nm HfZrO ferroelectric tunneling diodes show promising rectifying characteristics and efficient electromagnetic energy harvesting capabilities.
• These HfZrO diodes are suitable for IoT applications requiring wireless power transfer from ambient RF sources.
• The study highlights the potential of ALD-grown HfZrO for developing next-generation energy harvesting devices.