(DE4401626-A1)      In layer formation on a substrate by flowing a liq. contg. the layer-forming material over the substrate surface, a conc. drop of layer-forming material is produced perpendicular to the liq. flow direction such that the layer-forming material concn. is maximised at one side of the liq., pref. at the substrate-side of the liq..    Also claimed is an appts. for carrying out the above process.    USE -   Used esp. for prodn. of single crystal and polycrystalline thin layers on single crystal, polycrystalline, amorphous or other substrates of the same of different material, e.g. in thin film solar cell mfr..    ADVANTAGE -   Improved growth conditions are provided for formation of a crystalline layer on a substrate.    (US5503103-A)      A method for the formation of a layer on at least one substrate comprising the steps of bringing a liq. which contains a material for forming the layer to flow over a surface of the substrate by exerting a centrifugal force on the liq. which contains the material for forming the layer and flows over the surface of the substrate to be coated, and producing a concentration gradient of the layer-forming material in a direction, perpendicular to a direction of flow of the liquid, in such a manner, that the concentration of the layer-forming material becomes a max. at one side of the liquid, where a flow of the liq. is subjected to a centrifugal acceleration which is higher than acceleration required to transport the liq. over the substrate.    (JP8119791-A)      In layer formation on a substrate by flowing a liq. contg. the layer-forming material over the substrate surface, a conc. drop of layer-forming material is produced perpendicular to the liq. flow direction such that the layer-forming material concn. is maximised at one side of the liq., pref. at the substrate-side of the liq..    Also claimed is an appts. for carrying out the above process.    USE -   Used esp. for prodn. of single crystal and polycrystalline thin layers on single crystal, polycrystalline, amorphous or other substrates of the same of different material, e.g. in thin film solar cell mfr..    ADVANTAGE -   Improved growth conditions are provided for formation of a crystalline layer on a substrate.