Hyperspectral Photoluminescence Imaging for Spatially Resolved Determination of Electrical Parameters of Laser-Patterned Perovskite Solar Cells

Absolute calibrated hyperspectral photoluminescence (PL) imaging is utilized to access, in a simple and fast way, the spatial distribution of relevant solar cell parameters such as quasi-Fermi level splitting, optical diode factor, Urbach energies Eu, and shunt resistances Rsh, without the need for electrical measurements. Since these metrics play a significant role in evaluating the process windows for electrical series interconnection by laser patterning, this approach is followed to systematically locate and quantify electrical losses that may occur as a result of the laser-patterning process for monolithic series interconnection. It is shown that both picosecond and nanosecond laser pulses can be used for successful series interconnection. In both cases, only minor lateral material alterations occur, localized in a few & mu;m wide region adjacent to the edges of the scribe lines. Furthermore, the acquisition and analysis of these hyperspectral PL datasets provide insights in the material removal process, from which it is concluded that the perovskite is rather resilient against the thermal impact of the laser. Hyperspectral photoluminescence imaging followed by comprehensive data analysis provides access to the spatial distribution of optoelectronic and solar cell parameters without the need for specific electrical measurements. This methodology is presented here and demonstrated using laser-patterned perovskite solar cells as an example.image & COPY; 2023 WILEY-VCH GmbH

Automated summary

Absolute calibrated hyperspectral photoluminescence (PL) imaging is used to spatially map relevant solar cell parameters without electrical measurements. The process of laser patterning for monolithic series interconnection is evaluated, and it is found that both picosecond and nanosecond laser pulses can be used successfully. Hyperspectral PL imaging provides insights into the material removal process and the resilience of perovskite against the thermal impact of the laser.