Organic solvent soluble photoresists which are developable in aqueous alkaline solutions

A polymer that is insoluble in an aqueous-alkaline developer solution and soluble in organic solvents used for coating resists onto semiconductor substrates comprising:

• a plurality of polymer main chains linked together by bridge members, said polymer main chains comprising, in side chains, COOH groups or phenolic hydroxyl groups which are completely or partially substituted with acid-cleavable protecting groups;
• said bridge members comprising structural units of formula (I):
• ##STR12## wherein R.sub.2 is hydrogen, C.sub.1 -C.sub.18 alkyl, C.sub.5 -C.sub.10 cycloalkyl, C.sub.5 -C.sub.14 aryl or C.sub.6 -C.sub.30 aralkyl;
• wherein R.sub.3 is C.sub.1 -C.sub.18 alkyl, C.sub.5 -C.sub.10 cycloalkyl, C.sub.5 -C.sub.14 aryl or C.sub.6 -C.sub.30 aralkyl;
• said alkyl, cycloalkyl, aryl and aralkyl groups of R.sub.2 and R.sub.3 being optionally substituted with one or more hydroxyl groups, one or more nitro groups, one or more halogen atoms or combinations thereof;
• wherein X is a k+1 valent organic radical;
• wherein k is a number from 1 to 5;
• wherein 1 is a number from 0 to 4;
• and
• wherein said polymer, upon reaction with an acid, forms one or more cleavage products that are soluble in an aqueous-alkaline developer solution.