US 2020/0050106 Al  40  -continued  0  0  Feb. 13, 2020  [0397]  The content of the acid diffusion control agent in  the resist composition is preferably 0.001 % to 10% by mass,  and more preferably 0.01 % to 5% by mass with respect to  the total solid content of the composition.  [0398]  The acid diffusion control agents may be used  alone or in combination of two or more kinds thereof.  [0399]  The ratio of the photoacid generator and the acid  diffusion control agent in the resist composition, photoacid  generator/acid diffusion control agent (molar ratio), is pref› erably 2.5 to 300. From the viewpoints of the sensitivity and  the resolution, the molar ratio is preferably 2.5 or more, and  from the viewpoint of suppression of reduction in the  resolution as the resist pattern is thickened with aging after  exposure until the heating treatment, the molar ratio is  preferably 300 or less. The photoacid generator/acid diffu› sion control agent (molar ratio) is more preferably 5 .0 to  200, and still more preferably 7.0 to 150.  [0400]  Examples of the acid diffusion control agent  include the compounds (amine compounds, amido group› containing compounds, urea compounds, nitrogen-contain› ing heterocyclic compounds, and the like) described m  paragraphs <0140> to <0144> of JP2013-011833A.  [0401]  <(E) Hydrophobic Resin>  [0402]  The resist composition may include a hydrophobic  resin other than the resin (A), in addition to the resin (A).  [0403]  Although it is preferable that the hydrophobic resin  is designed to be unevenly distributed on a surface of the  resist film, it does not necessarily need to have a hydrophilic  group in its molecule as different from the surfactant, and  does not need to contribute to uniform mixing of polar  materials and nonpolar materials.  [0404]  Examples of the effect of addition of the hydro› phobic resin include a control of static and dynamic contact  angles of a surface of the resist film with respect to water and  suppression of out gas.  [0405]  The hydrophobic resin preferably has any one or  more of a "fluorine atom", a "silicon atom", and a "CH$_{3 }$ partial structure which is contained in a side chain moiety of  a resin" from the viewpoint of uneven distribution on the  film surface layer, and more preferably has two or more  kinds. Incidentally, the hydrophobic resin preferably has a  hydrocarbon group having 5 or more carbon atoms. These  groups may be contained in the main chain of the resin or  may be substituted in the side chain.  [0406]  In a case where hydrophobic resin includes a  fluorine atom and/or a silicon atom, the fluorine atom and/or  the silicon atom in the hydrophobic resin may be included in  the main chain or the side chain of the resin.  [0407]  In a case where the hydrophobic resin includes a  fluorine atom, as a partial structure having a fluorine atom, 