MicroLink has developed epitaxial lift-off (ELO), a technology for making large areas of thin, flexible, high-efficiency solar cells. The cells are fabricated using metal organic chemical vapor deposition (MOCVD). A release layer is deposited directly on top of the GaAs substrate, and multi-junction solar cells are then deposited on the release layer.
The presence of the release layer permits the solar cell epitaxial structure to be removed from the substrate without damage. A metal backing layer is first applied to the solar cell structure in order to provide mechanical support for the solar cell after lift-off. After removal of the substrate conventional solar cell fabrication is performed on the multi-junction structure. ELO process technology allows significant cost reductions since the GaAs substrate can be reused for subsequent growths of additional solar cells.