Method for forming quarter-pitch patterns

摘要

A method for forming quarter-pitch patterns is described. Two resist layers are formed. The upper resist layer is defined into first patterns. A coating that contains or generates a reactive material making a resist material dissolvable is formed over the lower resist layer and the first patterns. The reactive material is diffused into a portion of each first pattern and portions of the lower resist layer between the first patterns to react with them. The coating is removed. A development step is performed to remove the portions of the first patterns and the portions of the lower resist layer, so that the lower resist layer is patterned into second patterns. Spacers are formed on the sidewalls of the remaining first patterns and the second patterns. The remaining first patterns are removed, and portions of the second patterns are removed using the spacers on the second patterns as a mask.

主权项

1. A method for forming quarter-pitch patterns, comprising:
forming a lower resist layer and an upper resist layer in sequence; defining the upper resist layer into a plurality of first patterns; forming, over the lower resist layer and the first patterns, a coating that contains or generates a reactive material that makes materials of the lower resist layer and the upper resist layer dissolvable in development; diffusing the reactive material into a portion of each of the first patterns and into portions of the lower resist layer between the first patterns to react with them; removing the coating; performing a development step to remove the portions of the first patterns and the portions of the lower resist layer, so that the lower resist layer is patterned into a plurality of second patterns; forming a plurality of spacers on sidewalls of the remaining first patterns and sidewalls of the second patterns; and removing the remaining first patterns, and removing portions of the second patterns using the spacers on the second patterns as a mask.