Patent ID: 8563439
Filing Date: 2013-10-22
Classification: H01L

Abstract:
1. A method of pitch reduction, the method comprising: providing a substrate; forming a first material layer over the substrate; forming a second material layer on the first material layer; forming a hardmask layer on the second material layer; forming a first imaging layer on the hardmask layer; patterning the first imaging layer to form a plurality of first features over the hardmask layer, the plurality of first features having a first pitch between adjacent first features, etching the hardmask layer utilizing the first imaging layer as a mask to transfer the plurality of first features into the hardmask layer and expose a portion of a top surface of the second material layer; removing the first imaging layer to expose the etched hardmask layer; forming a second imaging layer on the etched hardmask layer and the portion of the top surface of the second material layer; patterning the second imaging layer to form a plurality of second features over the second material layer, the plurality of second features having the first pitch between adjacent second features, the plurality of first features of the etched hardmask layer and the plurality of second features of the second imaging layer being alternately arranged on the top surface of the second material layer; and etching the second material layer utilizing the etched hardmask layer and the patterned second imaging layer as a mask to transfer the plurality of first features and the plurality of second features into the second material layer.