Increasing the Specific Power of Epitaxial Lift-Off Solar Cells for Cost-Effective, High-Efficiency, Flexible Photovoltaics

MicroLink Devices has developed, and is currently producing, thin epitaxial lift-off inverted metamorphic solar cells for flexible solar sheets using a four-inch GaAs wafer platform. These cells have been demonstrated in a variety of applications including panels attached to Marines"backpacks and the wings of Raven and Puma unmanned aerial vehicles (UAVs). Although good system performance has successfully been demonstrated in the laboratory, during USMC Limited Operational Exercises, and during test Raven UAV flights, the widespread application of this technology is hindered to an extent by its cost. This SBIR proposal seeks to address this issue by applying innovative developments in solar cells and the latest technology in large-area MOVPE reactors to reduce the cost of the power generated to less than $50/W while increasing the specific power to greater than 1 W/g and maintaining terrestrial cell array efficiency greater than 20%. The proposed effort targets the development of large-area inverted metamorphic solar cell growth and process development on a six-inch platform to produce high efficiency solar sheets at a much greatly reduced cost, which could be used for numerous applications.