NOVELTY - Making surface imprinted films involves embedding nano-sized particles capable of charge separation in a conjugated polymer; applying a polymerizable layer on a substrate to form charge transport film layer; applying conjugated polymer/nano-sized particle mixture on second substrate to form a nano-sized particles bearing surface film layer to form a stamp surface; imprinting it into surface of the polymerizable film layer; polymerizing the film to promote shrinking and to form a conformal gap between stamp and film surface and filling the gap with a photoabsorbing material.    USE - For making film surface imprinted with nanometer-sized particles to produce micro and/or nano-structured electron and hole collecting interfaces (claimed) useful in e.g. photovoltaic devices and light guiding devices.    ADVANTAGE - The process overcomes the problem of prior art by avoiding the use of solvents, toxic components, or drugs, and elastomeric stamp processing. The process uses nanometer-sized particles having average particle size of 1-100 nm in diameter and 1-500 nm in length, (i.e. nano-structured electron and hole collecting interfaces) which provides fabrication of low mass and low volume devices.    DETAILED DESCRIPTION - Making film surface imprinted with nanometer-sized particles to produce micro and/or nano-structured electron and hole collecting interfaces involves: a1) embedding a nanometer-sized particles that produces charge separation interface, in a photoabsorbing conjugated polymer; b1) applying a polymerizable layer including a polymer on a first substrate to form a charge transport film layer; c1) applying the conjugated polymer/nanometer-sized particle mixture on a second substrate to form a nanometer-sized particles bearing surface film layer, where the nanometer-sized particles form a stamp surface; d1) imprinting the stamp surface into the surface of the polymerizable film layer to produce micro and/or nano-structured electron and hole collecting interfaces; e1) polymerizing the polymerizable film layer to promote shrinkage to form a conformal gap between stamp surface and the surface of polymerizable film layer; f1) filling the conformal gap with a photoabsorbing material to promote the generation of photoexcited electrons and transport to the charge separation interface. The conformal gap has a uniform width (60 - 100 nanometers) along the entire length of conformal gap, to insure sufficient generation of electrical current resulting from an excitation of the photoexcited electrons within the photoabsorbing material.