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## [2] Synthesis of Polymers 

[0310] Polymers for use in resist compositions were syn› thesized according to the following formulation. 

[0311] Synthesis of Polymer Pl 

[0312] In a flask under nitrogen atmosphere, 22 g of 1-t-butylcyclopentyl methacrylate, 17 g of 2-oxotetrahydro› furan-3-yl methacrylate, 0.48 g of dimethyl 2,2’-azobis(2- methylpropionate) (V-601 by Waka Pure Chemical Indus› tries, Ltd.), 0.41 g of 2-mercaptoethanol, and 50 g of MEK were combined to form a monomer/initiator solution. Another flask in nitrogen atmosphere was charged with 23 g of MEK, which was heated at 80° C. with stirring. With stirring, the monomer/initiator solution was added dropwise 

-continued 

## Synthesis Example 1 

to the flask over 4 hours. After the completion of dropwise addition, the polymerization solution was continuously stirred for 2 hours while maintaining the temperature of 80° C. The polymerization solution was cooled to room tem› perature, whereupon it was added dropwise to 640 g of methanol with vigorous stirring. The precipitate was col› lected by filtration, washed twice with 240 g of methanol, and vacuum dried at 50° C. for 20 hours, obtaining 36 g of Polymer Pl in white powder form (yield 90%). On GPC analysis, Polymer Pl had a Mw of 8,800 and a dispersity Mw/Mn of 1.94. 

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[0313] Synthesis of Polymers P2 to PS 

[0314] Polymers P2 to PS were synthesized by the same procedure as in Synthesis Example 1 aside from changing the type and amount of monomers. 

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## Synthesis Examples 2 to 5 

