Micro‐Concentrator Photovoltaics Using Fluidic Self‐Assembly Technology

Abstract

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 mm2 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.

Optimizing Binding Site Spacing in Fluidic Self-Assembly for Enhanced Microchip Integration Density

“…By reducing the binding site spacing, which is the distance between components on a PCB of the same area, more components can be arranged. If FSA technology is used for component assembly, it takes less than 1 min for thousands of components to be completely assembled [ 6 , 13 , 20 ]. In this respect, FSA is a way to list more components quickly and easily.…”

“…Fluidic self-assembly (FSA) technology allows for components to naturally interact and assemble within the fluid to form a desired structure by using the movement of fluid [ 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 ]. An irreversible bond is formed between a particle and an assembled substrate coated with molten alloy when a component comes into contact with one of the binding sites.…”

Integrated Micro‐Scale Concentrating Photovoltaics: A Scalable Path Toward High‐Efficiency, Low‐Cost Solar Power

“…This approach was shown for interconnecting 256 solar cells on an area of 40 × 40 mm 2 in ref. [79].…”

“…[43,99] FSA is an additional die-placement technology developed for micro-LEDs, [78] which has been validated for micro solar cells. [79] The cross-pollination from the micro-LED industry has already facilitated the development of various micro-CPV prototypes. [44,63,79] It will further contribute to reducing the cost in assembly and manufacturing of components of micro-CPV modules to expedite commercial deployment of the technology.…”

“…[79] The cross-pollination from the micro-LED industry has already facilitated the development of various micro-CPV prototypes. [44,63,79] It will further contribute to reducing the cost in assembly and manufacturing of components of micro-CPV modules to expedite commercial deployment of the technology. The ability to leverage existing industrial infrastructure hands micro-CPV a critical advantage over the classical CPV technology, as the latter relies on considerable hand labor or dedicated tools lacking economy of scale.…”