Aug. 8, 2019  3  US 2019/0243238 Al  substituent group ofR$^{1 }$can include an alkyl group  (RsP);  an  alkyl group including in its skeleton a divalent hetroatom› containing group in place of at least one methylene group of  the alkyl group; an alkenyl group having at least one  carbon-carbon single bond of the alkyl group substituted  with a carbon-carbon double bond; an aryl group  (MP);  a  hydroxy group; a halogen atom and the like.  [0034]  The afore-mentioned  Rsp  can include a linear,  branched, or cyclic alkyl group. The afore-mentioned  MP  can include an aromatic hydrocarbon group having 12 or  less carbon atoms such as a phenyl group, a naphthyl group  and the like, and an aromatic heterocyclic group which can  include a hetero atom in place of a carbon atom in the ring  structure. The substituent group regarding the alkyl group  (RsP),  the alkenyl group and the aryl group  (MP)  can  include the ones similar as the afore-mentioned alkyl group,  the alkeny  1  group and the ary  1  group of R  1 .  [0035]  The substituent group of R $^{1 }$regarding the halogen  atom can include a fluorine atom, a chlorine atom, a bromine  atom and the like.  [0036]  Here, the total number of carbon atoms in each of  R  1  when R  1  has a substituent group is preferably  1  to 20  including the substituent group, more preferably 5 to 15, and  especially preferably 6 to  10.  [0037]  As the substituent group of R 1, an alkyl group such  as a methyl group and the like, an alkoxy group, a hydroxy  group, an aryl group and the like are preferable.  [0038]  As the R1, an alkyl group such as a methyl group,  a n-butyl group and the like; and an aryl group such as a  phenyl group, a naphthyl group and the like are preferable.  [0039]  When the photosensitive compounds according to  some embodiments of the present invention have an onium  salt skeleton, the ones represented by the following formula  (2) can be mentioned. Here, the present invention is not  limited to these.  [0040]  In formula (2), Y represents either one of an atom  selected from the group consisting of an iodine atom, a  sulfur atom, a selenium atom, and a tellurium atom. When  Y is iodine atom, n is 2; and when Y is sulfur atom, selenium  atom, or tellurium atom, n is 3.  [0041]  R $^{2 }$is independently from each other selected from  the same candidates for the afore-mentioned R  1 , and at least  one R $^{2 }$in the formula (2) has the Te atom containing group  as a substituent group.  [0042]  The substituent group of R 2  can include the ones  similar to the substituent group of R  1 .  [0043]  The substituent group of R 2 ,  an alkyl group can  preferably include an ester group, a hydroxy group, a  sulfonyl group, a fluoro group and the like.  [0044]  When R 2  includes the Te atom containing group,  preferable R 2  is, from the viewpoint of membrane density,  solubility and the like, an aryl group having the Te atom  containing group. Among the aryl group, a phenyl group  having the Te atom contammg group, a naphthyl group  having the Te atom containing group and the like are more  preferable.  [0045]  When R $^{2 }$does not include the Te atom containing  group, the preferable R $^{2 }$can include, from the viewpoint of  solubility and the like, an alkyl group such as a methyl  group, an ethyl group, a n-propyl group, an isopropyl group,  an-butyl group, at-butyl group, a n-pentyl group, a n-hexyl  group, a cyclopentyl group, a cyclohexyl group, an adaman› tyl group and the like; an aryl group and the like.  [0046]  Two or more of R  $^{2 }$can be bonded to each other to  form a ring structure with  Y,  and the ring structure can  include a hetero atom. Here,  y+  preferably is not directly  bonded with the hetero atom and is bonded with a divalent  hydrocarbon group.  [0047]  As the cation which is formed by two or more ofR 2  being bonded to each other to form a ring structure with  Y,  the following can be mentioned for example. In the follow› ing, Y represents either one of a sulfur atom, a selenium  atom and a tellurium atom. Here, -R$^{3 }$-Te-R  1  corre› sponds to R 2  having the Te atom containing group repre› sented by formula  (1  ).  In the following example, a cation  having one Te atom containing group was shown, however,  the cation can have two or more of the Te atom containing  group, and the cation of the present invention is not limited  to the following examples. The R 3  can include the afore› mentioned bonding group and the like.  [0048]  The photosensitive compounds of some embodi› ments of the present invention preferably have two or more  of the Te atom containing group represented by formula  (1),  since absorption of electron beam or EUV becomes high.  [Chemical Formula 4]  [Chemical Formula 3]  (Photosensitive Compound Having an Onium Salt Skeleton)  0  y  y  y  y  I  I  I  I  R3  R3  R3  R3  I  I  I  I  Te  Te  Te  Te  I  I  I  I  RI  RI  RI  RI  CC SX)~ cc~ OX)~  +  #  #  +  #  y  y  I  I  R3  R3  I  I  Te  Te  I  I  RI  RI  0  II  CC SX)~  +  #  y  I  R3  I  Te  I  RI  (2) 