US Patent 7588657 Pattern-free method of making line gratings

In accordance with the invention, substrate-supported linear arrays are formed by the steps of adhering a thin layer of polymer between a pair of substrates and separating the substrates perpendicular to the layer. The polymer layer separates to form substrate-supported polymer gratings on both substrates, each grating having a period proportional to the thickness of the layer. The process has been used to make gratings with periods in the sub-micron range or larger over areas covering square centimeters.