US 2020/0401045 Al  44  Dec. 24, 2020  A-1  [0567]  A method for improving the surface roughness of a  pattern may be applied to a pattern formed by the pattern  forming method of the embodiment of the present invention.  Examples of the method for improving the surface rough› ness of a pattern include the method of treating a pattern by  plasma of a hydrogen-containing gas, as disclosed in the  specification of US2015/0104957A. In addition, known  methods as described in the specification of JP2004- [0566]  In order to prevent impurities from being incorpo› rated, it is preferable that various materials are stored in the  container  described  in  US2015/0227049A,  JP2015- 123351A, JP2017-013804A, or the like.  [0571]  Hereinbelow,  the  present  invention  will  be  described in more detail with reference to Examples. The  materials, the amounts of materials used, the proportions,  the treatment details, the treatment procedure, and the like  shown in the Examples below may be modified as appro› priate as long as the modifications do not depart from the  spirit of the present invention. Therefore, the scope of the  present invention should not be construed as being limited to  the Examples shown below.  [0572]  [Preparation of Actinic Ray-Sensitive or Radiation› Sensitive Resin Composition (for ArF Exposure)]  [0574]  <Resin (AXl)>  [0569]  [Method for Manufacturing Electronic Device]  [0563]  Examples of a method for removing impurities  such as metals from the various materials include filtration  using a filter. As for the filter pore diameter, the pore size is  preferably 10 nm or less, more preferably 5 nm or less, and  still more preferably 3 nm or less. As for the materials of a  filter, a polytetrafluoroethylene-made, polyethylene-made,  or nylon-made filter is preferable. As the filter, a filter which  has been washed with an organic solvent in advance may be  used. In the step of filtration using a filter, plural kinds of  filters connected in series or in parallel may be used. In a  case of using the plural kinds of filters, a combination of  filters having different pore diameters and/or materials may  be used. In addition, various materials may be filtered plural  times, and the step of filtering plural times may be a  circulatory filtration step. As the filter, a filter having a  reduced amount of eluates as disclosed in the specification  of JP2016-201426A is preferable.  the present invention, and the pattern forming method of the  embodiment of the present invention include no impurities  such as metal components, isomers, and residual monomers.  The content of the impurities included in these materials is  preferably 1 ppm or less, more preferably 100 ppt or less,  and still more preferably 10 ppt or less, and particularly  preferably, the impurities are not substantially included (no  higher than a detection limit of a measurement device).  235468A, the specification ofUS2010/0020297 A, and Proc.  of SPIE Vol. 8328 83280N-1 "EUV Resist Curing Technique  for L WR Reduction and Etch Selectivity Enhancement" may  be applied.  EXAMPLES  [0568]  In addition, a pattern formed by the method can  be used as a core material (core) of the spacer process  disclosed in, for example, the specification of JP1991- 270227 A (JP-803-270227 A) and the specification of  US2013/0209941A.  [0570]  Moreover, the present invention further relates  to a method for manufacturing an electronic device, the  method including the above-described pattern forming  method. The electronic device manufactured by the  method for manufacturing an electronic device of an  embodiment of the present invention is  suitably  mounted on electric or electronic equipment (for  example, home electronics, office automation (OA)› related equipment, media-related equipment, optical  equipment, and telecommunication equipment).  [0564]  In addition to the filtration using a filter, removal  of impurities by an adsorbing material may be per› formed, or a combination of filtration using a filter and  an adsorbing material may be used. As the adsorbing  material, known adsorbing materials can be used, and  for example, inorganic adsorbing materials such as  silica gel and zeolite, and organic adsorbing materials  such as activated carbon can be used. Examples of the  metal adsorbing agent include those disclosed in the  specification of JP2016-206500A.  [0573]  Various components contained in the actinic  ray-sensitive or radiation-sensitive resin composition  shown in Table 4 are shown below.  [0565]  In addition, as a method for reducing the impu› rities such as metals included in the various materials,  metal content selects the less material as a raw material  constituting the various materials, performing filtering  using a filter of the raw material constituting the  various materials, equipment the inner and a method  such as performing distillation under conditions sup› pressing as much where available equal to contamina› tion is lined with TEFLON (registered trademark). It is  also preferable to perform a glass lining treatment in all  steps of the manufacturing facility for synthesizing  various materials (a resin, a photoacid generator, and  the like) of the resist component in order to reduce  impurities such as metals to a ppt order. Preferred  conditions in the filtering using a filter to be performed  on the raw material constituting the various materials  are the same as the above-described conditions.  [0575]  The resins (A-1 to A-11 and B-1 to B-3) shown  in Table 4 are shown below.  [0576]  Further, the weight-average molecular weight  (Mw) and the dispersity (Mw/Mn) of the resins A-1 to  A-11 and B-1 to B-3 were measured by GPC (carrier:  THF (tetrahydrofuran)) (amount converted in terms of  polystyrene). In addition, the compositional ratio (ratio  % by mole) of the resin was measured by  $^{13}$C-nuclear  magnetic resonance (NMR). 