Resist composition suitable for short wavelength exposure and resist pattern forming method

A method of forming a resist pattern comprising the steps of:

• coating a resist composition on a substrate to form a resist film, the resist composition comprising:
• a polymer containing a carboxyl group with a protective group at a side chain of a monomer unit, the polymer being insoluble to a basic aqueous solution and becoming soluble to a basic aqueous solution when the protective group of the carboxyl group is eliminated from the side chain, the protective group of the carboxyl group being represented by:
• where R is a hydrogen atom or a single-bonded hydrocarbon group, n is an integer 1 to 4, and R is attached to a position other than the ester bonded position;
• and a photoacid generator which generates acid inertly upon light exposure;
• selectively exposing the resist film with light capable of inducing dissolution of the photoacid generator;
• and
• developing the exposed resist film with a basic aqueous solution.