METHOD OF FORMING FINE PATTERNS OF SEMICONDUCTOR DEVICE USING DOUBLE PATTERNING PROCESS

摘要

A method for forming a fine pattern of a semiconductor device by using a double patterning process is provided to form easily a pattern having a fine pitch by overcoming a limit of resolution in a photolithography process. A hard mask layer is formed on first and second regions of a substrate(100) including an etching target layer(120). A plurality of mask patterns(130,150a) and a buffer layer(140) are formed on the hard mask layer. A first etch process is performed to etch the buffer layer and the hard mask layer in the first and second regions by using an RIE(Reactive Ion Etching) method. A second etch process is performed to form a hard mask pattern(124b) by accumulating polymer byproducts(160) in the first region and etching the hard mask layer in the second region. The polymer byproducts are removed from the first region. An etching target layer pattern is formed by etching the exposed surface of the etching target layer.