Project Name: Rapid Patterning and Advanced Device Structures for Low Cost Manufacturable Crystalline Silicon IBC Cells
Funding Opportunity: PVRD
SunShot Subprogram: Photovoltaics
Location: Newark, DE
SunShot Award Amount: $1,124,491
Awardee Cost Share: $125,084
Project Investigator: Steven Hegedus
This project is developing a new method for the manufacturing of interdigitated back contact (IBC) solar cells with metal contacts on the backside of the wafer, which allows for greater light harvesting on the front surface due to absence of grid shadowing. The new process will use direct laser patterning of the metal electrodes to isolate the positive and negative contacts, as well as laser firing of dopants to create localized contacts regions between the metal and the silicon wafer.
The research team will work to develop a back surface patterning strategy using direct laser patterning of the metal electrodes to isolate the positive and negative contacts. The strategy also uses laser firing of dopants to create very small localized contact regions between the metal and the silicon wafer, which is amenable to rapid manufacturing with high yield and avoids degrading or damaging the interface. The team will also create a device structure and surface passivation scheme that is compatible with the low cost patterning process, while integrating of the back surface processing with metal electrodes.
The IBC solar cell has reached very high efficiencies because the metal contacts on the backside of the wafer allow greater light harvesting on the front surface due to absence of grid shadowing. However, the costs are higher than standard silicon cells due to the challenges of patterning and isolating the positive and negative electrodes on the back surface. This project will enable a new, low-cost patterning strategy of the metal layer of IBC cells without disrupting the high-quality protective layers on the rear surface. The result will be a lower cost silicon IBC cell with 25% efficiency, leading to a levelized cost of energy of less than $0.06 per kilowatt hour.