“…Devices were protected by a mask during He implantation. In previous works, 13,14 we have carried out a detailed study for identical fully implanted junctions and, hence, the intentionally doped p ϩ -and n-type layers of the junction were also obtained by Mg and Si ion implantation, respectively, fabricated on identical substrates with identical implantation parameters and annealing conditions. The only difference with the current He implantation-isolated samples is that, in those samples, isolation among devices was achieved by wet etching using a solution of 1H 2 O 2 :1H 2 SO 4 during 10 min, giving rise to mesa structures.…”