Enhancement of light trapping in thin-film hydrogenated microcrystalline Si solar cells using back reflectors with self-ordered dimple pattern

In this article, the light-trapping effect of textured back surface reflectors in thin-film Si solar cells is investigated. A unique substrate with a periodic dimple pattern has been developed by utilizing anodic oxidation of Al as a self-ordering process. n-i-p hydrogenated microcrystalline Si (μc-Si:H) cells fabricated on the Al substrate with a period of 0.9 μm show an improved infrared response compared to those fabricated on randomly textured substrates. A high short circuit current density of 24.3 mA/cm2 has been achieved in a 1-μm-thick μc-Si:H cell by adopting the patterned Al substrate.