Methods of forming patterns

A method of forming sub-resolution features, the method comprising:

• exposing a photoresist layer formed over a substrate to a first ultraviolet light (UV) radiation having a first wavelength of 365 nm or longer through a first mask, the photoresist layer comprising first portions exposed to the first UV radiation and second portions unexposed to the first UV radiation after exposing with the first UV radiation, the second portions having a first critical dimension;
• developing the photoresist layer after exposing the photoresist layer to the first UV radiation to remove the first portions;
• depositing a resin over the photoresist layer;
• exposing the second portions to a second UV radiation having a second wavelength;
• and
• developing the photoresist layer after exposing the photoresist layer to the second UV radiation to form the sub-resolution features having a second critical dimension less than the first critical dimension, the sub-resolution features comprising a trench between the photoresist layer and the resin.

A method of forming sub-resolution features, the method comprising:

• loading a substrate in a lithography tool, the substrate comprising a photoresist layer formed thereon;
• generating, in the lithography tool, a first ultraviolet light (UV) radiation having a first wavelength of 365 nm or longer;
• exposing the photoresist layer to the first UV radiation through a single mask, the photoresist layer comprising first reacted portions exposed to the first UV radiation and first unreacted portions unexposed to the first UV radiation after exposing with the first UV radiation, the first unreacted portions having a first height and a first critical dimension;
• generating, in the lithography tool, a second UV radiation having a second wavelength;
• exposing the photoresist layer to the second UV radiation, the second UV radiation being a blanket radiation with no pattern, the exposing forming, from the first unreacted portions, second reacted portions exposed to the second UV radiation and second unreacted portions unexposed to the second UV radiation after exposing with the second UV radiation, the second unreacted portions having a second height and a second critical dimension less than the first critical dimension, the second height being less than the first height, wherein exposing to the second UV radiation is performed using a pixel-based projection system having an array of independently addressable projection points;
• and
• forming a plurality of features, the forming comprising developing the photoresist layer after exposing the photoresist layer to the second UV radiation, the developing removing the first reacted portions and the second reacted portions while retaining the second unreacted portions to form the plurality of features.