3. ALD applications for 2nd and 3rd generation solar cells

Economic breakthroughs are possible by using elements that are abundant or in smaller quantities, and by developing low-cost deposition techniques. This is one of the challenges facing thin-film solar cells (2nd generation) and advanced concepts often based on nanostructures (3rd generation). These technologies are at very different stages of maturity, but in all of them the advantages of the ALD technique are being exploited.

A direct application of ALD is the encapsulation of solar cells on flexible substrates, which need to be protected from ambient humidity and oxygen. Indeed, ALD's ability to deposit inorganic films at low temperatures that are transparent to the solar spectrum, opaque, seamless and mechanically robust, as well as the development of roll-to-roll reactors, has enabled a significant reduction in costs. For example, a 50-100 nm ALD-Al _...