US Patent 7547504 Pattern reversal employing thick residual layers

The present invention features a method of patterning a substrate that includes forming, on the substrate, a first layer having a first pattern and selectively shifting in tone, as well as along a first direction, a subsequent pattern formed into the same layer that corresponds to the first pattern. To that end, one method of the present invention includes generating into the first layer, a second pattern having a shape inverse to the first pattern. A third pattern is then transferred into the first layer that has a shape inverse to the second pattern.