Methods for small trench patterning using chemical amplified photoresist compositions

A method for forming a pattern on a substrate, comprising:

• providing a substrate;
• forming a photosensitive layer on a substrate, the photosensitive layer comprising a polymer that turns soluble to a developer solution, a photo-acid generator (PAG) at a first concentration that decomposes to form acid in response to a first exposure energy, and a photo-base generator (PBG) at a second concentration that decomposes to form a base in response to a second exposure energy;
• exposing the photosensitive layer to the first exposure energy through a first mask;
• exposing the photosensitive layer to the second exposure energy through a second mask, wherein a portion of the layer exposed to the second exposure energy overlaps with a portion exposed to the first exposure energy;
• baking the photosensitive layer;
• and
• developing the exposed photosensitive layer.

A method for forming a pattern on a substrate, comprising:

• providing a substrate;
• forming a photosensitive layer on a substrate, the photosensitive layer comprising a polymer that turns soluble to a developer solution, a photo-acid generator (PAG) at a first concentration that decomposes to form acid in response to a first exposure energy, and a photo-base generator (PBG) at a second concentration that decomposes to form a base in response to a second exposure energy;
• adjusting the first concentration, second concentration, or both to improve contrast and/or a critical dimension in the pattern;
• adjusting an intensity of the first exposure energy, second exposure energy, or both to improve contrast and/or a critical dimension in the pattern;
• exposing the photosensitive layer to the first exposure energy through a first mask;
• exposing the photosensitive layer to the second exposure energy through a second mask, wherein a portion of the layer exposed to the second exposure energy overlaps with the a portion exposed to the first exposure energy;
• baking the photosensitive layer;
• and
• developing the exposed photosensitive layer.