Thin-film encapsulation of inverted indium-tin-oxide-free polymer solar cells by atomic layer deposition with improvement on stability and efficiency.

Atomic layer deposition (ALD) technology is employed to encapsulate inverted indium-tin-oxide-free polymer solar cells (IFSCs) with a structure of Al/TiOx/P3HT:PC61BM/PEDOT:PSS. The encapsulation layer, Al2O3, is deposited by ALD on the light incident surface. The thickness of the Al2O3 layer can thus be optimized through optical simulation to minimize light loss of IFSCs. Based on optical calculation, we encapsulated the device (85 nm thick active layer) with a 30 nm thick Al2O3 layer. The resulting ALD encapsulated IFSCs show much better device performance and higher stability than the glass-encapsulated ones. [ABSTRACT FROM AUTHOR]