APPLICATIONS OF TECHNOLOGY:
- Concentrator solar cells
- Solar farms and power plants
- Communications satellites
- Space exploration
- Cost effective, single semiconductor design
- Power conversion efficiency over 40%
- Full solar spectrum sensitivity
- Highly durable materials
Wladyslaw Walukiewicz and Kin Man Yu of Berkeley Lab have designed a new semiconducting material that will enable the fabrication of high efficiency solar cells at a fraction of the price of other technologies. Unlike conventional high efficiency solar cells designed with three semiconductors, the Berkeley Lab Intermediate Band Solar Cell (IBSC) requires only one semiconductor to convert an entire solar spectrum of low-, intermediate-, and high-energy photons into electric current. The invention will enable the conversion of more than 40% of solar radiation into energy, efficiency competitive with triple-junction solar cells, but at significantly lower fabrication costs.
The Berkeley Lab researchers are the first to demonstrate an IBSC using a gallium-arsenide (GaAs) semiconductor with a dilute amount of nitrogen. The Berkeley Lab IBSC has an intermediate band that acts as a stepping-stone for low energy photons to “excite” or move electrons from the valence band to the upper conduction band, forming electron-hole pairs that produce electric current. In addition, the researchers have discovered that adding dilute amounts of nitrogen and antimony to aluminum-gallium-arsenide or AlGaAs, an alloy commonly used in the electronics industry, results in an opaque alloy, aluminum-gallium-nitride-arsenide-antimonide or AlGaNAsSb, which easily grows on commonly available substrates.
With its streamlined design and use of cost-efficient, commercially available materials, the Berkeley Lab invention is the best candidate for ushering Intermediate Band Solar Cells into the marketplace at lower production costs than conventional triple-junction solar cells.
DEVELOPMENT STAGE: Proven principle.
STATUS: Patent pending. Available for licensing or collaborative research.
SEE THESE OTHER BERKELEY LAB TECHNOLOGIES IN THIS FIELD:
REFERENCE NUMBER: WIB-2621