Spacer lithography

Abstract

Ultrafine dimensions are accurately and efficiently formed in a target layer using a spacer lithographic technique comprising forming a first mask pattern, forming a cross-linkable layer over the first mask pattern, forming a cross-linked spacer between the first mask pattern and cross-linkable layer, removing the cross-linkable layer, cross-linked spacer from the upper surface of the first mask pattern and the first mask pattern to form a second mask pattern comprising remaining portions of the cross-linked spacer, and etching using the second mask pattern to form an ultrafine pattern in the underlying target layer. Embodiments include forming the first mask pattern from a photoresist material capable of generating an acid, depositing a cross-linkable material comprising a material capable of undergoing a cross-linking reaction in the presence of an acid, and removing portions of the non-cross-linked layer and cross-linked spacer from the upper surface of the first mask pattern before removing the remaining portions of the first mask pattern and remaining noncross-linked layer.