Patent ID: 8492282
Filing Date: 2013-07-23
Classification: H01L

Abstract:
1. A method of forming features in an electronic device, the method comprising: forming mandrels defining a first pattern in a first masking layer on one or more underlying layers comprising a target layer, the first pattern including spaces between the mandrels, and having a first pitch; depositing a layer with a chemically active species in the spaces between the mandrels; removing the layer with the chemically active species; subsequently depositing a second masking layer to at least partly fill the spaces of the first pattern, the second masking layer contacting the one or more underlying layers through the spaces between the mandrels; subsequently photolithographically defining a photolithographic pattern in a portion of the electronic device spaced apart from and on a same level as the mandrels; forming sacrificial structures to define gaps between at least parts of the mandrels and at least parts of the second masking layer; after depositing the second masking layer and forming the sacrificial structures, removing the sacrificial structures to define a second pattern having a second pitch smaller than the first pitch, wherein the second pattern includes the at least parts of the mandrels and intervening mask features alternating with the at least parts of the mandrels; and subsequently subjecting the mandrels and intervening mask features to an anisotropic etch to round top corners of the intervening mask features.