NOVELTY - The method involves dispensing a material i.e. nanoparticle ink, on a surface of a substrate (104) e.g. glass substrate, where the material comprises nanoparticles (302) i.e. silica nanoparticles, and a solvent selected from one ethanol and poly-4-vinylphenol. A relative motion between the substrate and a tool i.e. wire-wound rod, physically separated from the substrate by a barrier is established so as to completely distribute the material over the surface and forms a nascent layer having a uniform thickness. Removal of the solvent from the nascent layer is enabled.    USE - Method for forming a textured surface i.e. nano-textured surface, on a substrate e.g. soda-lime glass substrate, rigid substrate such as semiconductor substrate, ceramic substrate, glass substrate, metal substrate and dielectric substrate, and flexible substrate such as polymer substrate, polyethylene substrate, polyethylene terephthalate substrate, ferropaper, carbon-impregnated paper and parylene-N substrate, for an optoelectronic semiconductor device e.g. solar cell such as amorphous silicon-based p-type/intrinsic/n-type (p-i-n) solar cell, by using a high-speed, large scale, roll-to-roll coating equipment. Can also be used for LED, fuel cell, laser, optical modulator, thermionics application, thermal photovoltaic application and photodetector.    ADVANTAGE - The method enables evaporating the solvent from the nanoparticle ink so as to inducing the nanoparticles to assemble into a texture layer, thus rapidly and inexpensively forming a large-area substrate having the nano-textured surface with a simple and inexpensive manufacturing equipment such as high-speed material transfer system. The method enables allowing the device to improve light absorption over a wavelength band of interest, improved light coupling into a semiconductor layer and reduce reflectivity over the wavelength band of interest.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of a substrate after assembling nanoparticles of nascent layer into a texture layer.    Substrate (104)    Texture layer (106)    Nanoparticles (302)