Silicon-containing polymers comprising recurring units of three
components represented by the general formula (1) are novel wherein R1,
R2 and R3 are hydrogen or C1-10 alkyl, R4,
R5 and R6 are hydrogen, C1-20 alkyl or haloalkyl,
or C6-20 aryl, R7 is C4-20 alkyl, n is 1 to 5,
p, q and r are positive numbers. Resist compositions comprising the polymers are
sensitive to high-energy radiation and have a high sensitivity and resolution at
a wavelength of less than 300 nm and improved resistance to oxygen plasma etching
##STR1##
