Micro-Concentrator Photovoltaics Using Fluidic Self-Assembly Technology

This paper is the first to report a simple and cost-effective method for modularizing an array of gallium arsenide (GaAs) solar cells on a plastic circuit board using fluidic self-assembly (FSA) technology and the combination thereof with a polymer lens array to implement micro-concentrator photovoltaics (micro-CPV). Using FSA and low-melting-point solder, the GaAs cells are successfully self-assembled into a 2D array in 1 min. Micro-CPVs consisting of 36 and 256 cells are manufactured by aligning a polymer concentrator fabricated by a drop-on-demand droplet dispensed lens array mold on the solar cell array. The micro-CPVs generate 21.31 and 112.96 mW of power, respectively, under 1 sun AM 1.5G illumination. In each module, only 1.69 and 2.27 mm(2) of GaAs are used for producing 1 mW; in other words, the implemented micro-CPV platform consumes 4.21 and 3.14 times less material than a flat-panel GaAs array. The proposed method for implementing a GaAs-based solar cell array enables the efficient fabrication of a compact micro-CPV with a thickness of only 4 mm owing to the absence of a cooling module. This technology is expected to potentially increase the practical usability of III-V compound solar cells in the energy industry.