An electrochemical/electrically controllable device including at least one carrier substrate provided with an electroactive layer or a stack of electroactive layers placed between a lower electrode and an upper electrode. The upper electrode includes at least one electronically conductive layer, especially a transparent one, based on doped indium oxide or on doped tin oxide or on doped zinc oxide, which is at least partially crystallized in the form of crystallites having a mean size of between 5 and 100 nm, especially between 10 and 50 nm.