Patent ID: 8129080

Claim:
A method of patterning a substrate using a dual-tone development procedure, comprising: forming a layer of radiation-sensitive material on the substrate, wherein the layer of radiation-sensitive material comprises a resist material having a polymer backbone and a plurality of protecting groups; creating a first patterned layer of exposed radiation-sensitive material by exposing the layer of radiation-sensitive material using a first EM radiation and a reticle having a plurality of masking features, and heating the first patterned layer of exposed radiation-sensitive material thereby creating a plurality of high exposure regions having a first number of de-protected groups, a plurality of medium exposure regions having a second number of de-protected groups, and a plurality of low exposure regions having a third number of de-protected groups in the low exposure regions; determining a first threshold profile for a first positive tone development procedure for the first patterned layer of exposed radiation-sensitive material using at least one of the first number of de-protected groups in the high exposure regions, the second number of de-protected groups in the medium exposure regions, and the third number of de-protected groups in the low exposure regions; determining a first set of limits for a first dual-tone development procedure; modifying the first threshold profile if the first threshold profile exceeds one or more of the first set of limits; and developing the first patterned layer of exposed radiation-sensitive material if the first threshold profile does not exceed at least one of the first set of limits.