METHOD FOR REDUCING CRITICAL DIMENSIONS USING MULTIPLE MASKING STEPS

摘要

is provided a method of forming features in the etch layer . The first mask is formed over the etch layer , defines a plurality of spaces having a first mask width . The side wall layer is formed on the first mask . Features are etched into the etch layer through the sidewall layer , the features have a smaller width than the width of the space defined by the first mask . The first mask and sidewall layer are removed . Further mask is formed in etching the upper layer , further mask defines a plurality of spaces with a width . Side wall layer is formed on the upper additional mask . Features are etched into the etch layer through the sidewall layer, the width of the features is smaller than the width of the space defined by the first mask . Add layer mask and the sidewall is removed .