Abstract: The actinic ray-sensitive or radiation-sensitive resin composition of the present invention contains (A) a resin capable of increasing the solubility in an alkaline developer by the action of an acid, and (C) at least one selected from the group of compounds represented by the following formula (ZI-3), (ZI-4) or (ZI-5) and capable of generating an acid upon irradiation of actinic rays or radiation, wherein the resin (A) contains at least one repeating unit having a group capable of decomposing by the action of an acid to leave a leaving group having a ring structure, and the leaving group having a ring structure has at least one of a polar group as a substituent and a polar atom as a part of the ring structure, and a compound derived from the leaving group having a ring structure has a log P value of not less than 0 and less than 2.8.

Abstract: An actinic-ray-sensitive or radiation-sensitive resin composition capable of forming a pattern having excellent critical dimension uniformity (CDU) in the line width, and a pattern forming method using the same are provided. The actinic-ray-sensitive or radiation-sensitive resin composition of the present invention includes (A) a resin containing a repeating unit having a specific lactone structure and a repeating unit having a specific monocyclic alicyclic structure, which increases a solubility in an alkaline developer by the action of an acid, and (B) a compound having a specific structure, which generates an acid upon irradiation with an actinic-ray or a radiation.

Abstract: An actinic ray-sensitive or radiation-sensitive resin composition including: (PA) a compound having a proton acceptor functional group and undergoing decomposition upon irradiation with an actinic ray or radiation to generate a compound reduced in or deprived of proton acceptor property or changed to be acidic from being proton acceptor-functioning, wherein a molar extinction coefficient ? of the compound (PA) at a wavelength of 193 nm as measured in acetonitrile solvent is 55,000 or less, and a pattern forming method using the composition are provided.

Abstract: An actinic ray-sensitive or radiation-sensitive resin composition includes: (A) a resin capable of increasing a solubility of the resin (A) in an alkali developer by an action of an acid; and (B) a compound capable of generating an acid upon irradiation with an actinic ray or radiation, wherein (B) the compound capable of generating an acid upon irradiation with an actinic ray or radiation is contained in an amount of 10 to 30 mass % based on the entire solid content of the actinic ray-sensitive or radiation-sensitive resin composition, and a pattern forming method uses the composition.