Process for forming wide and narrow conductive lines

摘要

Sidewall spacers formed on sides of mandrels are separated by first gaps in a first region and separated by wider second gaps in a second region. The second gaps are filled while a capping layer caps the first gaps. The capping layer is etched thereby exposing mandrels in the first region, which are removed. An underlying layer is patterned using the sidewall spacers separated by first gaps to form word lines in the first region and using sidewall spacers with filled second gaps to form select lines in the second region.

主权项

1. A method of forming a semiconductor device including a first line pattern and a second line pattern comprising:
forming a first layer of a first material; forming a plurality of core portions of a second material on an upper surface of the first layer, forming a plurality of spacers of a third material along sides of the plurality of core portions, the plurality of spacers including first pairs of spacers in a first region corresponding to the first line pattern, a first pair of spacers separated by a first distance, the plurality of spacers also including second pairs of spacers that are formed in a second region corresponding to the second line pattern, a second pair of spacers separated by a second distance that is greater than the first distance; depositing a layer of a capping material that caps first gaps between the first pairs of spacers and does not cap second gaps between the second pairs of spacers; depositing the third material to fill the second gaps; etching back the third material such that the third material deposited on the capping material is removed and the third material remains in the second gaps; forming masking portions that cover the third material remaining in the second gaps; subsequently, performing isotropic etching thereby removing the capping material that caps the first gaps between the first pairs of spacers and removing core portions between the first pairs of spacers in the first region; subsequently, removing the masking portions; and subsequently, patterning the first layer by anisotropic etching to form the first line pattern in the first region and to form the second line pattern in the second region, the second line pattern being wider than the first line pattern.