To provide another new resist composition for use at a wavelength of 193 nm or lower, in particular at a wavelength of 157 nm, which has not only high transparency at these short wavelengths but also other key properties including good plasma etching resistance and adhesion.

A fluorine-containing copolymer includes: (i) a repeat unit derived from at least one ethylenically unsaturated compound including at least one fluorine atom covalently bonded to an ethylenically unsaturated carbon atom; and (ii) a repeat unit derived from a group comprising CH2=CHO2CR15, CH2=CHOCH2R15 and CH2=CHOR15, wherein in formulas R15 is nearly 4C-20C saturated alkyl group and optionally containing one or a plurality of ether oxygens under the condition that a ratio of carbon atoms to a hydrogen atom is 0.58 or more.