Funding Opportunity: SuNLaMP
SunShot Subprogram: Photovoltaics
Location: National Renewable Energy Laboratory, Golden, CO
Amount Awarded: $4,000,000

Low-cost III-V photovoltaics have the potential to lower the levelized cost of energy (LCOE) because III-V cells outperform silicon in terms of efficiency and annual energy harvesting efficiency. In this project, researchers will address both the high costs of III-V epitaxy and single crystal substrates. Hydride vapor phase epitaxy (HVPE) is the most promising inexpensive, rapid-growth technique for high efficiency, III-V materials. The continued development of high-throughput HVPE, will be coupled with novel epitaxial liftoff strategies to enable III-V solar cells that are cost-competitive under one-sun conditions.

APPROACH

In this project, researchers will develop solar cell materials with high bulk minority-carrier lifetimes and well-passivated heterojunction interfaces while developing lifted-off structures for the incorporation of a back reflector. The project will develop a kinetic model of the HVPE growth of III-Vs and incorporate growth kinetics into the established computational fluid dynamics modeling capability, with the eventual goal of faster progress and a higher level of understanding. Researchers will develop capabilities to effectively remove these devices from the parent wafer, enabling substrate reuse for significant cost mitigation.

INNOVATION

Researchers aim to develop a 25% efficient III-V solar cell grown at high rate using HVPE coupled with an effective substrate reuse technology. By reducing costs of III-V cells, this technology can outperform crystalline silicon in efficiency, energy yield, and lower balance of system costs.