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The novel fluorine-containing polymer of the present invention possesses dry etching resistance higher than that of polymers prepared using norbomene and transparency thereof even in a vacuum ultraviolet region is excellent as compared with polymers prepared using norbornene. 

Also the copolymer obtained by copolymerizing a fluo› roolefin with the novel unsaturated compound having a monocyclic structure of the present invention which has an acid-reactive functional group directly bonded to a ring and partly contains fluorine possesses an excellent dry etching resistance and high transparency when used for a resist. 

What is claimed is: 

1. A fluorine-containing unsaturated cyclic compound rep- resented by the formula (l)(a): 

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wherein Z $^{3 }$are the same or different and each is -RF-Z 4 , in which Z 4 is at least one functional group selected from the group consisting of OH group, COOH group, a derivative of carboxylic acid group and a functional group protected by a protective group which can convert the functional group to OH group by reaction with an acid; Rf $^{3 }$is a fluorine-contain› ing alkylene group which has 1 to 30 carbon atoms and may have ether bond; nl 1 is an integer of from 1 to 4. 

2. The fluorine-containing unsaturated cyclic compound of $_{55 }$ claim 1, wherein in the formula (1 )(a), Z $^{3 }$is represented by the formula: 

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(l)(a) 

wherein Rf4 is a perfluoroalkylene group which has 1 to 10 carbon atoms and may have ether bond; R $^{4 }$is hydrogen atom or an alky 1 group having 1 to 10 carbon atoms. 

3. The fluorine-containing unsaturated cyclic compound of claim 1, wherein in the formula (1 )(a), Z $^{3 }$is represented by the formula: 

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wherein R: $^{15 }$is an alkylene group which has 1 to 5 carbon atoms and may have ether bond or a fluorine-containing alky› lene group which has 1 to 5 carbon atoms and may have ether bond; RF is a fluorine-containing alkyl group which has 1 to 10 carbon atoms and may have ether bond; RF is hydrogen atom, an alkyl group having 1 to 10 carbon atoms or a fluo› rine-containing alkyl group which has 1 to 10 carbon atoms and may have ether bond; nl 2 is 0 or 1. 

4. The fluorine-containing unsaturated cyclic compound of claim 3, wherein Z $^{3 }$is represented by the formula: 

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wherein RF and R:f6 are as defined in said formula; n13 is 0 or an integer of from 1 to 5; n14 is 0 or 1. 

5. The fluorine-containing unsaturated cyclic compound of claim 3, wherein RF and R:f6 are the same or different and each is a perfluoroalkyl group having 1 to 5 carbon atoms. 

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