US 2020/0192222 Al  104  Jun.  18,2020  -continued  -continued  0  0  0  N- I  O  N- I  N- QQaj  /  ~  I  ~o  $^{8}$~o  $^{8}$~o  II  II  II  0  0  0  ~N  0-u~o  0  [0080]  Exemplary of the halide ion are fluoride, chloride,  bromide and iodide ions.  [0081]  In the resist composition, it is preferred in view of  sensitivity and acid diffusion suppressing effect to use the  iodized benzene ring-containing quencher in an amount of  0.001 to 30 parts by weight, more preferably 0.005 to 20  parts by weight per 100 parts by weight of the base polymer.  The iodized benzene ring-containing quencher may be used  alone or in admixture.  [0082]  The base polymer in the resist composition is an  iodized polymer, referred to as Polymer A, hereinafter.  Polymer A preferably comprises recurring units having the  formula (al) or recurring units having the formula (a2).  These units are simply referred to as recurring units (al) and  (a2).  Base Polymer  (a2)  (al) 