Patent ID: 7582413

Claim:
A method of exposing a lithographic substrate to radiation, said substrate having a first layer of a first positive tone developable material at least partially overlying the substrate and a second layer of a second positive tone developable material with a preselected absorbance for the radiation and at least partially overlying the first layer, comprising: patterning the second layer with features of the second positive tone developable material in accordance with a first pattern of the radiation by: exposing the second layer to the first pattern of the radiation, and developing the second positive tone developable material; and exposing the first layer and said features to a second pattern of the radiation whereby one or more areas of exposure of the second pattern include one or more of said features, and whereby between one or more pairs of adjacent features there is an area of exposure of the second pattern extending inward from the adjacent features and terminating at an unexposed area of the second pattern, and whereby during the respective exposures of the second and first layers said absorbance prevents exposure to above energy-to-clear exposure dose of at least a portion of the first positive tone developable material underneath exposed portions of the second positive tone developable material.