Project Name: Field-Effect Passivation by Desired Charge Injection into SiNx Passivation in Crystalline-Silicon Solar Cells
Funding Opportunity: Solar Energy Technologies Office Fiscal Year 2018 Funding Program (SETO FY2018)
SETO Research Area: Photovoltaics
Location: Tempe, AZ
SETO Award Amount: $1,120,000
Awardee Cost Share: $280,000
Principal Investigator: Jeong-Mo Hwang
-- Award and cost share amounts are subject to change pending negotiations --
This team developed a gas plasma method that creates passivation layers in silicon solar cells. Passivation layers allow charge carriers to pass through the cell more easily, enabling it to more efficiently convert energy from sunlight into electricity. The plasma is a cost-effective alternative to aluminum oxide for creating a passivation layer on the surface of silicon in solar cells, and can also lead to increased cell efficiency. However, there are technical issues that need to be resolved. This project will examine methods to resolve these technical issues to facilitate technology commercialization.
Conventionally, a layer of aluminum oxide passivates silicon solar cells. The team will instead use a cost-effective gas plasma to add electrical charge to the layers surrounding the silicon wafer that serves as the base of the cell. The team will work to reduce charge loss that results from the high-temperature step of the plasma treatment and small defects created in the cell. They will test different plasma intensities, gas types, and other properties to assess changes in the charge at the passivated surface, and identify the changes that lead to better passivation.
The gas plasma does not cause film deposition or corrosion inside the passivation treatment chamber, and it reduces defects that adding a metal oxide layer would cause. Because plasma charging yields higher efficiency and lower costs, the team expects that near-future commercialization of this technology will create new jobs in the charging-tool equipment business.