Methods are disclosed, such as those involving increasing the density of
isolated features in an integrated circuit. In one or more embodiments, a
method is provided for forming an integrated circuit with a pattern of
isolated features having a final density of isolated features that is
greater than a starting density of isolated features in the integrated
circuit by a multiple of two or more. The method can include forming a
pattern of pillars having a density X, and forming a pattern of holes
amongst the pillars, the holes having a density at least X. The pillars
can be selectively removed to form a pattern of holes having a density at
least 2X. In some embodiments, plugs can be formed in the pattern of
holes, such as by epitaxial deposition on the substrate, in order to
provide a pattern of pillars having a density 2X. In other embodiments,
the pattern of holes can be transferred to the substrate by etching.