Generation of a Charge Carrier Gradient in a 3C-SiC/Si Heterojunction with Asymmetric Configuration

Area of Science:

• Materials Science
• Semiconductor Physics
• Optoelectronics

Background:

• Asymmetric semiconductor junctions are crucial for developing advanced photovoltaic and self-powered devices.
• Understanding charge carrier gradient generation is essential for optimizing these devices.

Purpose of the Study:

• To investigate the generation of a charge carrier gradient in a 3C-SiC/Si heterojunction with an asymmetric electrode configuration.
• To explore the lateral photovoltaic effect in these heterojunctions under varying illumination conditions.

Main Methods:

• Fabrication of 3C-SiC/Si heterojunction devices with asymmetric electrode widths.
• Illumination using laser beams (405, 521, 637 nm) and a halogen bulb.
• Measurement of lateral photovoltage by scanning a laser spot across the heterojunction surface.

Main Results:

• A significant charge carrier gradient was successfully generated in the 3C-SiC/Si heterojunction.
• The highest lateral photovoltage reached 130.58 mV under specific conditions (electrode width ratio 5, 637 nm wavelength, 1000 μW illumination).
• Lateral photovoltage was observed even under uniform illumination at zero bias, an unusual finding.

Conclusions:

• The study elucidates the underlying physics of the lateral photovoltaic effect in nano-heterojunctions.
• The findings highlight the potential of these heterojunctions for developing novel optoelectronic sensors and self-powered devices.