Electrical and microstructural characterisation of microcrystalline silicon layers and solar cells

This paper attempts to clarify the link between microstructure of hydrogenated microcrystalline silicon (/spl mu/c-Si:H) and layer transport properties as well as electrical performances of solar cells. Analysis of a series of layers shows that coplanar transport properties in /spl mu/c-Si:H (as evaluated by /spl sigma//sub dark/, /spl sigma//sub photo/ and L/sub amb/) relate to the size of nanocrystal conglomerates (as observed by TEM and AFM) and not to the average size of individual nanocrystals (as evaluated from XRD). Bifacial Raman crystallinity factors are defined and introduced in order to clarify the relationship between solar cell open-circuit voltage V/sub oc/ and crystallinity of the top and bottom interface regions. For a variety of nip and pin /spl mu/c-Si:H solar cells, V/sub oc/ linearly decreases as the average of the crystallinity factors measured on actual cells increases.