3 March 2011
RFMD fabricates dual-junction PV cells
Radio-frequency microelectronic component maker RF Micro Devices Inc of Greensboro, NC, USA says it has achieved a key performance milestone related to its commercialization of photovoltaic (PV) cells. Specifically, it has fabricated dual-junction PV cells that integrate gallium arsenide (GaAs) and indium gallium phosphide (InGaP) PV junctions using the firm’s standard 6-inch semiconductor equipment. RFMD says that this clears the way for it to develop triple-junction structures, with the ultimate goal of developing a commercially viable and high-volume-capable compound semiconductor-based process for high-performance PV cells.
“With this achievement, RFMD is demonstrating we possess the critical technologies to produce a low-cost PV product with competitive solar cell conversion efficiency, supported by the quality, reliability, and volumes that characterize the cellular handset market,” says president & CEO Bob Bruggeworth.
In mid-2009, RFMD announced that it had entered into a multi-year Cooperative Research And Development Agreement (CRADA) with the US Department of Energy’s National Renewable Energy Laboratory (NREL) to develop a production-capable process technology for high-performance PV cells.
RFMD says that fabrication of the dual-junction PV cells and the associated performance characteristics are consistent with results achieved by NREL in its development of inverted metamorphic multi-junction (IMM) technology. NREL’s technology has demonstrated one of the world's highest reported solar cell conversion efficiencies (40.8%), and continued substantial improvements in efficiency are anticipated.
RFMD says that its fabrication of the dual-junction PV cells was realized using its existing manufacturing capabilities and robust supply chain, which are optimized for high volume, low cost, reliability and performance. The firm says that the conversion efficiency achieved across its 6-inch wafers was exceptionally uniform, enabling high device yields and tight distributions in concentrated photovoltaic (CPV) product performance.
RFMD says that its development efforts related to a compound semiconductor-based process for PV cells are broadly applicable across technologies, including IMM as well as conventional triple-junction germanium-based CPV devices. RFMD anticipates multiple opportunities related to PV cells, and is engaged with CPV system integrators and solar cell module manufacturers.