US 9,703,193 B2  103  104  -continued  -continued  . (B) may  .  he base resm  .  foregoing umts,  ~  n oxetane nng or  In addition to the  ring units havmg a  oxirane ring- rise recur  .  f oxetane or  .nk din  further comp  lymerizat10n o  .  film is crossh  e  •rane ring. Capo  that the resist  . t film is thus  ox1  . .  units ensures  d region of res1s  contammg  .  The expose  .  d reg10n.  h es1stance.  •t  the expose  .  and etc  r  rring um  d  • retent10n  . .  the recu  improve  m  mer prov1dmg  h  below, but  f the mono  •  are s own  Examples o  ring or oxir~e nndg fined above.  h  •ng an oxetane  .  RA  is as  e  av1  h  to Herem  not limited t ere  . 