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to 300, more preferably from 5 .0 to 200, still more preferably from 7.0 to 150. If this molar ratio is excessively small, the sensitivity and/or resolution may be reduced, whereas if the molar ratio above is excessively large, thickening of the pat› tern may be caused between exposure and heating (post bak- ing). 

## [E] Hydrophobic Resin 

The composition of the present invention may further con› tain a hydrophobic resin. When a hydrophobic resin is con- tained, the hydrophobic resin is unevenly distributed to the surface layer of the composition film and in the case of using water as the immersion medium, the receding contact angle of the film for the immersion liquid can be increased. In turn, the followability of the immersion liquid to the film can be enhanced. 

The receding contact angle of the film after baking and before exposure is preferably from 60 to 90°, more preferably 65° or more, still more preferably 70° or more, yet still more preferably 75° or more, at a temperature of 23–3° C. and a humidity of 45–5%. 

The hydrophobic resin is, as described above, unevenly distributed to the interface but unlike a surfactant, need not have necessarily a hydrophilic group in the molecule and may not contribute to uniform mixing of polar/nonpolar sub› stances. 

In the immersion exposure step, the immersion liquid must move on a wafer following the movement of an exposure head that is scanning the wafer at a high speed and forming an exposure pattern. Therefore, the contact angle of the immer› sion liquid with the resist film in a dynamic state is important, and the electron beam-sensitive or extreme ultraviolet-sensi- tive resin composition is required to have a performance of allowing a liquid droplet to follow the high-speed scanning of an exposure head with no remaining. 

The hydrophobic resin (HR) is preferably a resin having at least either a fluorine atom or a silicon atom. The fluorine atom or silicon atom in the hydrophobic resin (HR) may be present in the main chain of the resin or may be substituted on the side chain. By virtue of the hydrophobic resin containing at least either a fluorine atom or a silicon atom, hydrophobic- ity (water followability) on the film surface is increased and the development residue (scum) is decreased. 

The hydrophobic resin (HR) is preferably a resin having, as the fluorine atom-containing partial structure, a fluorine atom-containing alkyl group, a fluorine atom-containing cycloalkyl group or a fluorine atom-containing aryl group. 

The fluorine atom-containing alkyl group (preferably hav› ing a carbon number of 1 to 10, more preferably from 1 to 4) is a linear or branched alkyl group with at least one hydrogen atom being substituted for by a fluorine atom and may further have other substituents. 

The fluorine atom-containing cycloalkyl group is a mono› cyclic or polycyclic cycloalkyl group with at least one hydro› gen atom being substituted for by a fluorine atom and may further have other substituents. 

The fluorine atom-containing aryl group includes an aryl group (e.g., phenyl group, naphthyl group) with at least one hydrogen atom being substituted for by a fluorine atom and may further have other substituents. 

Preferred examples of the fluorine atom-containing alkyl group, fluorine atom-containing cycloalkyl group and fluo- 

rine atom-containing aryl group include the groups repre› sented by the following formulae (F2) to (F 4 ), but the present invention is not limited thereto: 

In formulae (F2) to (F4), each ofR$_{57 }$to R$_{68 }$independently represents a hydrogen atom, a fluorine atom or an alky 1 group, provided that at least one ofR$_{57 }$to R$_{6}$ i, at least one ofR$_{62 }$to R$_{64 }$and at least one of R$_{65 }$ to R$_{68 }$ are a fluorine atom or an alkyl group (preferably having a carbon number of 1 to 4) with at least one hydrogen atom being substituted for by a fluorine atom. It is preferred that all of R$_{57 }$to R$_{61 }$ and all of R$_{65 }$ to R$_{67 }$ are a fluorine atom. Each of R$_{62}$, R$_{63 }$and R$_{68 }$is preferably an alkyl group (preferably having a carbon number of 1 to 4) with at least one hydrogen atom being substituted for by a fluorine atom, more preferably a perfluoroalkyl group having a carbon number of 1 to 4. R$_{62 }$and R$_{63 }$may combine with each other to form a ring. 

Specific examples of the group represented by formula (F2) include p-fluorophenyl group, pentafluorophenyl group and 3,5-di(trifluoromethyl)phenyl group. 

Specific examples of the group represented by formula (F3) include trifluoromethyl group, pentafluoropropyl group, pentafluoroethyl group, heptafluorobutyl group, hexafluor› oisopropyl group, heptafluoroisopropyl group, hexafluoro(2- methyl)isopropyl group, nonafluorobutyl group, octafluor› oisobutyl group, nonafluorohexyl group, nonafluoro-tert› butyl group, perfluoroisopentyl group, perfluorooctyl group, perfluoro( trimethy 1 )hexyl group, 2,2,3 ,3-tetrafluorocyclo bu› tyl group and perfluorocyclohexyl group. Among these, hexafluoroisopropyl group, heptafluoroisopropyl group, hexafluoro(2-methyl)isopropyl group, octafluoroisobutyl group, nonafluoro-tert-butyl group and perfluoroisopentyl group are preferred, and hexafluoroisopropyl group and hep- tafluoroisopropyl group are more preferred. 

Specific examples of the group represented by formula (F4) include ----C(CF$_{3}$ ) $_{2}$OH, ----C(C$_{2}$F$_{5}$ ) $_{2}$OH, -C(CF$_{3}$ ) ( CH$_{3}$)O H and-CH( CF $_{3}$)0 H, with ----C( CF $_{3}$ ) $_{2}$0 H being pre- ferred. 

Suitable repeating units having a fluorine atom include the followings. 

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