Patent ID: 9023224
Filing Date: 2015-05-05
Classification: H01L

Abstract:
1. A method of forming a spacer patterning mask, comprising: providing a substrate; depositing, on the substrate, an interface layer, a core film and a first hard mask; patterning the core film and the first hard mask to form strips that include the core film and the first hard mask, wherein a first separation distance between neighboring strips is based on a second separation distance between patterns of the spacer patterning mask; depositing a spacer patterning layer over the core film and the first hard mask; planarizing the spacer patterning layer by using the first hard mask as a stop layer, wherein the planarizing comprises using chemical mechanical polishing (CMP); etching the spacer patterning layer, wherein an amount of etching is determined based on a separation distance and dimensions of patterns in the spacer patterning mask; depositing a second hard mask; dry etching the second hard mask to expose the spacer patterning layer, wherein a third separation distance between sections of the second hard mask has a predefined relation to the second separation distance between patterns of the spacer patterning mask; dry etching the spacer patterning layer to form a spacer pattern; removing the first hard mask and second hard mask; and removing the core film to obtain the spacer patterning mask.