III-V

Fraunhofer ISE researchers utilized a new front metallization technique to produce a III-V gallium arsenide solar cell. For mask and plate front metallization, they used a new two-step printing scheme that reportedly allows for the realization of extremely narrow mask openings.

Chinese researchers have used metal-organic chemical vapor deposition (MOCVD) to produce a 12 cm2, five-junction solar cell with a minimal number of mismatch dislocations. The cell has an open-circuit voltage of 4.727 V, a short-circuit current density of 860 mA/m2, and a fill factor of 86.38%.

UK scientists have developed a solar cell based on a layer of gallium-arsenide just 80 nanometers thick, with similar performance to much thicker devices. It showed excellent resistance to damage from radiation exposure, making it ideal for high-radiation satellite/space applications.

Scientists in the United States have fabricated a triple-junction solar cell that reached 39.5% efficiency – a world record for any type of cell under one-sun illumination. Though relying on materials and processes that are still too costly for most commercial uses, the concept could soon see actual applications in powering satellites and other space-bound technology.

The German research institute said the gallium arsenide cell has achieved the highest efficiency to date for the conversion of light into electricity.

The cell, which looks externally like a device with a two-terminal architecture, was built with III-V semiconductor layers that were connected to the silicon sub-cell on the atomic level. The cell may be used in electrically powered aircraft and drones.

A collaboration between the U.S. National Renewable Energy Laboratory and Australia’s University of New South Wales has yielded a new efficiency record of 32.9% for a tandem cell device utilizing III-V materials. Key to the achievement was a new technique enabling the researchers to take advantage of “quantum wells” in the material that serve to trap charges and enable tuning of the cell bandgap to absorb more of the light spectrum.

A consortium of European research institutes has received €10.6 million in EU funding to establish pilot production of a high efficiency module concept developed by Swiss startup Insolight. The module combines high efficiency multijunction cells with a solar concentrator lens and has previously demonstrated 29% efficiency.

Scientists at Germany’s Fraunhofer Institute for Solar Energy Systems have broken two of their own records for cell efficiency, working with silicon and III-V material tandem cells. The institute hit 34.1% on a triple junction cell using wafer bonding technology and 24.3% by directly depositing III-V layers onto a silicon solar cell.

A research paper from scientists at the U.S. National Renewable Energy Laboratory outlines a new approach to the production of gallium arsenide based cells. The approach, termed ‘germanium on nothing’, could enable the cost effective, high volume production of PV cells based on III-V materials such as gallium arsenide.