Picosun Oy, a Finland-based global manufacturer of atomic layer deposition (ALD) equipment, says ROD-SOL, a European Union 7th Framework Programme-funded research project, has achieved promising results for a solar cell technology used with its ALD equipment.
The goal of this multinational, inter-European, three-year project was to increase the efficiency of solar cells and reduce the costs of their manufacturing. This goal has been achieved with a silicon nanorod-based concept, the company says. The amount of silicon can be significantly reduced by growing the light-trapping nanorod ‘forests’ (thickness from < 1Î¼m to a few Î¼m at most) on cheaper substrates such as glass or flexible foils.
This research has led to energy conversion efficiencies of greater than 9%, with good long-term cell stability. Due to their three-dimensional geometry, the nanorod forests have a high active surface area, which enables efficient light absorption, according to Picosun Oy. In addition, the location of the p-n junction is much closer to the surface than in normal solar cells, which improves the minority carrier charge transport and, thus, the amount of electricity that can be extracted from the cell.
Due to the micrometer/sub-micrometer dimensions of the nanorod forests, ALD has proven to be an ideal technique for manufacturing some of the most crucial cell components, according to Picosun Oy.