An electrostatic discharge (ESD) protection device including: a substrate including: a first, second and third doped regions, the second doped region disposed between the first and third doped regions, the second doped region has a first conductivity type and a first doping concentration and the first and third doped regions have a second conductivity type and a second doping concentration; first and second doped terminal regions disposed within the first and second doped regions, respectively; and a doped island region disposed within the second doped region, the first and second doped terminal regions and doped island region have the second conductivity type and a third doping concentration, the third doping concentration higher than the first and second doping concentrations; and conductive terminals respectively coupled to the doped terminal regions; and an insulation layer arranged on the substrate between the conductive terminals and covering at least the second doped region.