Jan. 10, 2019  3  US 2019/0010119 Al  branched, or cyclic alkoxy group having 1 to 6 carbon atoms  optionally substituted with a halogen atom; A  1  represents a  single bond or a linear, branched, or cyclic alkylene group  having 1 to 10 carbon atoms optionally having an ether bond  between a carbon-carbon bond thereof; "a" is an integer  satisfying Osas5+2w-b; and "b" is an integer of 1 to 3.  [0020]  The inventive resist composition is a resist com› position that causes few defects and is excellent in lithog› raphy performance, having regulated acid diffusion, in pho› tolithography using a high energy beam as a light source.  [0021]  It  is preferable that the component (A) be shown by  the following general formula (A2),  (A2)  wherein R1, R 2 , and R 3  each independently represent any of  a hydrogen atom, the partial structure shown by the general  formula (Al), a linear, branched, or cyclic monovalent  hydrocarbon group having 1 to 20 carbon atoms optionally  containing a hetero atom, and a direct bond with the adjacent  benzene ring; "p", "q", and "r" each independently represent  an integer of Oto 5; and when "p", "q", or "r" represents 2  or more, a plurality ofR$^{1}$s, R$^{2}$s, or R$^{3}$s corresponding thereto  are either the same or different; when p+q+r is 2 or more, a  plurality ofR$^{1}$s, R$^{2}$s, or R$^{3}$s are optionally bonded with each  other to form a ring together with carbon atoms of the  benzene ring to which they are bonded, and R 1  and R 2 , R 1  and R 3 , or R 2  and R 3  are optionally bonded with each other  to form a ring together with the two benzene rings to which  they are bonded and the sulfur atom in the formula; with the  proviso that at least one of R 1 , R 2 , and R 3  is the partial  structure shown by the general formula (Al), with the * in  the general formula (Al) being a bonding site with the  benzene ring in this case; and  z- represents a monovalent  amon.  [0022]  The inventive resist composition is particularly  excellent in lithography performance when the component  (A) is shown by the general formula (A2) as described  above.  [0023]  It  is preferable that the component (A) be a sulfo› nium salt in which  R’a  and  w1’  each represent a trifluorom› ethyl group, and  Ra  and R $^{6 }$each represent a hydrogen atom.  [0024]  When the component (A)  has  the group(s)  described above, the component (A) is easily synthesized  and makes it possible to markedly improve the lithography  performance such as LER and CDU.  [0025]  It  is preferable that the component (A) be a sulfo› nium salt in which L  la  is a single bond.  [0026]  When L1a of the component (A) is a single bond as  described above, the component (A) is easily synthesized.  Additionally, the shorter chain portion regulates the mobility  of the sulfonium salt in the resist film to improve the effect  of regulating acid diffusion as a result.  wherein  RA  has the same meaning as defined above; each  R  12  independently represents a halogen atom, a linear,  branched, or cyclic acyloxy group having 2 to 8 carbon  atoms optionally substituted with a halogen atom, a linear,  branched, or cyclic alkyl group having 1 to 6 carbon atoms  optionally substituted with a halogen atom, or a linear,  branched, or cyclic alkoxy group having 1 to 6 carbon atoms  [0037]  It  is preferable that the repeating unit decompos› able by action of an acid to increase solubility of the  component (B) into an alkaline developer be shown by the  following general formula (B2),  [0036]  When the component (B) contains the repeating  unit described above, the inventive resist composition shows  better solubility to an alkaline developer in preparation  thereof as a chemically amplified positive resist composi› tion.  [0035]  It  is preferable that the resist composition be a  chemically amplified positive resist composition, and the  component (B) further contain a repeating unit decompos› able by action of an acid to increase solubility of the  component (B) into an alkaline developer in addition to the  repeating unit (Bl).  [0034]  When the anion of the component (A) is an aryl› sulfonate anion or an alkanesulfonate anion as described  above, the composition generates an acid with appropriate  acidity.  [0033]  It  is preferable that the component (A) be a sulfo› nium salt in which the anion is an arylsulfonate anion or an  alkanesulfonate anion.  [0032]  The inventive resist composition is particularly  excellent in lithography performance when the anion of the  component (A) is a sulfonate anion.  [0031]  It  is preferable that the component (A) be a sulfo› nium salt in which the anion is a sulfonate anion.  [0030]  When  Rxa  of the component (A) is a hydrogen  atom or a methoxymethyl group as described above, the  component (A) is easily synthesized and is excellent in  miscibility. Additionally, the acid diffusion is regulated due  to the hydroxy group or the ether bonds, which makes it  possible to improve the lithography performance much  further.  [0029]  It  is preferable that the component (A) be a sulfo› nium salt in which  Rxa  is a hydrogen atom or a methoxym› ethyl group.  [0028]  WhenA 1$_{a }$ of the component (A) is an ether bond as  described above, it is possible to improve the lithography  performance moreover.  [0027]  It  is preferable that the component (A) be a sulfo› nium salt in which A  la  is an ether bond.  (B2) 