Influence of interface morphologies on amorphous silicon thin film solar cells prepared on randomly textured substrates

The influence of the interface morphologies on amorphous silicon thin-film solar cells prepared on randomly textured substrates was studied. A simple three-dimensional geometrical model was developed to describe the surface morphology of amorphous silicon films and thin-film solar cells. The simulated surface morphologies are confirmed by experimental measurements. A detailed understanding of the interface morphologies is required to gain insights in the light-trapping of silicon thin-film solar cells on randomly textured substrates and derive strategies to improve the light-trapping properties. The morphology of amorphous silicon solar cell layers is calculated by using atomic force microscope scans of the randomly textured substrates and the thickness of layers as input data. The influence of the interface morphologies on the surface roughness, average film thickness and size of surface textures is investigated. Finally the influence of these parameters on the light-trapping and optical losses is discussed.

► Influence of solar cell interfaces on solar cells was investigated.
► An approach was developed that predicts the interface morphology of amorphous silicon solar cells.
► Simulated interface morphologies are confirmed with experimental data.
► Interface morphologies define roughness of the back contact and thicknesses of solar cell layers.
► Prediction algorithm allows for further understanding and optimization of light trapping in thin film solar cells.