Windowless CdSe/CdTe solar cells with differentiated back contacts: J-V, EQE, and photocurrent mapping

Area of Science:

• Materials Science
• Renewable Energy
• Nanotechnology

Background:

• Thin film photovoltaic devices are crucial for renewable energy.
• Previous research focused on symmetric CdSe/CdTe devices.
• Submicrometer patterning offers potential for enhanced performance.

Purpose of the Study:

• To investigate the performance of windowless CdSe/CdTe thin film photovoltaic devices with in-plane submicrometer patterning.
• To explore device performance in asymmetric configurations with varying CdSe contact widths.
• To improve dimensional tolerance in device fabrication.

Main Methods:

• Fabrication of photovoltaic cells on interdigitated comb electrodes.
• Electrodeposition of CdSe and pulsed laser deposition of CdTe.
• Scanning photocurrent microscopy for local current collection efficiency analysis.
• Complementary current-voltage and external quantum efficiency measurements.
• Modeling of carrier transport and recombination.

Main Results:

• Windowless CdSe/CdTe devices with submicrometer patterning were successfully fabricated.
• Asymmetric device performance was evaluated with varying CdSe contact widths.
• Scanning photocurrent microscopy revealed spatial variations in performance.
• Device performance exceeded 5% efficiency under simulated AM 1.5 illumination.
• The highest achieved efficiency was 5.9%.

Conclusions:

• The study successfully demonstrated windowless CdSe/CdTe thin film photovoltaic devices with advanced patterning.
• Device performance is consistent under local and blanket illumination, as supported by modeling.
• The developed devices show promising efficiency for solar energy applications.