High sensitive position-dependent photodetection observed in Cu-covered Si nanopyramids

Area of Science:

• Materials Science
• Nanotechnology
• Photovoltaics

Background:

• Silicon nanostructures are recognized for their light absorption properties, primarily utilized in solar cells.
• The lateral photovoltaic effect (LPE) is a phenomenon sensitive to the position of incident light.

Purpose of the Study:

• To investigate the enhancement of the lateral photovoltaic effect (LPE) in copper-nanoparticle-covered random silicon nanopyramids (Cu@Si-pyramid).
• To explore the broadband photoelectric response and position-sensitivity of these engineered nanostructures.

Main Methods:

• Fabrication of copper-nanoparticle-covered random silicon nanopyramids (Cu@Si-pyramid).
• Characterization of the lateral photovoltaic effect (LPE) across a broadband spectrum (405-780 nm).
• Finite-difference time-domain (FDTD) simulation to understand the underlying physical mechanisms.

Main Results:

• Significantly enhanced LPE observed in Cu@Si-pyramid structures.
• Broadband photoelectric response demonstrated from 405 nm to 780 nm.
• LPE sensitivity was found to increase from 74.0 to 157.9 mV mm⁻¹ as the linear detection region decreased from 3 mm to 1 mm.

Conclusions:

• Copper nanoparticle decoration dramatically boosts the LPE in silicon nanopyramids.
• The Cu@Si-pyramid system exhibits excellent position-sensitive photodetecting capabilities.
• This research highlights the potential of silicon nanopyramid systems for advanced photodetector applications.