Resist Polymer 1  Reference Polymer 1  86  US 9,152,050 B2  85  Mw=6,700  Mw/Mn=l.58  Mw=S,200  Mw/Mn=l.69  Reference Polymer 1  ~  0  0  0  Resist Polymer 1  A positive resist composition in solution form was pre- pared by dissolving a resist film surface-modifying polymer  (Polymers 1 to 7, shown above), a polymer obtained by con› ventional radical polymerization (Resist Polymers 1 to 5,  shown below) and components in a solvent in accordance  with the formulation of Table 1 and filtering through a filter  with a pore size of0.2 µm.  EUV Lithography Patterning Test  Outgassing Test Simulated for EUV Lithography  The resist composition (see Table 3) was coated onto a  HMDS-primed 12-inch wafer to form a resist film of 60 nm  thick. Using a resist outgassing tool (EUV Tech), the resist  film was exposed to EB in a varying dose, baked (PEB) at the  temperature shown in Table 3, and developed in an alkaline  developer (2.38 wt % TMAH aqueous solution). E0 is the  dose at which the film thickness became 0 nm. After the wafer  was subjected to flood exposure at the dose of E0, the thick› ness of contaminants deposited on Witness Plate was mea- sured by spectral ellipsometry. The results are shown in Table  3.  Mw=6,900  Mw/Mn=l.68  Resist Polymer 2  Examples and Comparative Examples  Preparation of Resist Composition  Resist Polymer 2 