Acid-amplifier having acetal group and photoresist composition including the same

A photoresist composition comprising:

• 0.01˜5.0 weight % of an acid-amplifier having a structure of following Formula 1;
• wherein in Formula 1, R is C4˜C20 mono-cyclic or multi-cyclic saturated hydrocarbon, R1 is C1˜C10 linear hydrocarbon, C1˜C10 perfluoro compound, or C5˜C20 aromatic compound, Ra and Rb are independently hydrogen atom or C1˜C4 saturated hydrocarbon and A is independently oxygen atom (O) or sulfur atom (S);
• 3˜10 weight % of a photo-sensitive polymer;
• 0.05˜10 weight part pf a photo-acid generator with respect to 100 weight part of the photosensitive polymer;
• and
• an organic solvent.

A method for forming a photoresist pattern, comprising the steps of:

• a) coating a photoresist composition on a substrate to form a photoresist layer;
• wherein the photoresist composition comprises 0.01˜5.0 weight % of an acid-amplifier having a structure of following Formula 1, wherein
• in Formula 1, R is C4˜C20 mono-cyclic or multi-cyclic saturated hydrocarbon, R1 is C1˜C10 linear hydrocarbon, C1˜C10 perfluoro compound or C5˜C20 aromatic compound, Ra and Rb are independently hydrogen atom or C1˜C4 saturated hydrocarbon and A is independently oxygen atom (O) or sulfur atom (S);
• 3˜10 weight % of a photo-sensitive polymer;
• 0.05˜10 weight part of a photo-acid generator with the respect to 100 weight part of the photo-sensitive polymer;
• and
• an organic solvent;
• b) exposing the photoresist layer to a light;
• c) heating the exposed photoresist layer;
• and
• d) developing the heated photoresist layer to form the photoresist pattern.