A merged-PN-Schottky, MPS, diode, comprising: - a semiconductor substrate, having an N type conductivity and a first doping level; - a drift layer of semiconductor material on the substrate, having a bottom surface which faces said substrate and a top surface opposite to the bottom surface, the N type conductivity and a second doping level lower than the first doping level; - a doped region of P-type conductivity, extending in the drift layer at the top surface; - an ohmic contact (19"), in direct electrical contact with the doped region at the top surface; - a plurality of cells of N-type conductivity and said second doping level, extending in the drift layer within and through the doped region and facing the top surface; - an anode metallization on said top surface, in electrical contact with the doped region through the ohmic contact (19") and in direct electrical contact with said cells, such as to form a junction-barrier, JB, diode with said doped region and Schottky diodes with said cells, wherein the JB diode and the Schottky diodes define an active area of the MPS diode, the MPS diode further comprising an edge-termination region of P-type conductivity completely surrounding the active area and extending as a prolongation of the doped region, wherein: the doped region has, in top-plan view, a grid-shaped layout delimiting said plurality of cells, each cell has a same geometry among quadrangular, quadrangular with rounded corners and circular, and said ohmic contact (19") extends at said doped region with continuity along the grid-shaped layout, wherein, in said top-plan view, the MPS diode has a layout that is symmetric with respect to any line of symmetry passing through the centroid of the geometric shape delimited by the edge-termination region, wherein a region of P-type conductivity formed by the doped region and the edge-termination region has a quadrangular shape with rounded corners, said cells being absent at said rounded corners. - a semiconductor substrate, having an N type conductivity and a first doping level; - a drift layer of semiconductor material on the substrate, having a bottom surface which faces said substrate and a top surface opposite to the bottom surface, the N type conductivity and a second doping level lower than the first doping level; - a doped region of P-type conductivity, extending in the drift layer at the top surface; - an ohmic contact (19"), in direct electrical contact with the doped region at the top surface; - a plurality of cells of N-type conductivity and said second doping level, extending in the drift layer within and through the doped region and facing the top surface; - an anode metallization on said top surface, in electrical contact with the doped region through the ohmic contact (19") and in direct electrical contact with said cells, such as to form a junction-barrier, JB, diode with said doped region and Schottky diodes with said cells, wherein the JB diode and the Schottky diodes define an active area of the MPS diode, the MPS diode further comprising an edge-termination region of P-type conductivity completely surrounding the active area and extending as a prolongation of the doped region, wherein: the doped region has, in top-plan view, a grid-shaped layout delimiting said plurality of cells, each cell has a same geometry among quadrangular, quadrangular with rounded corners and circular, and said ohmic contact (19") extends at said doped region with continuity along the grid-shaped layout, wherein, in said top-plan view, the MPS diode has a layout that is symmetric with respect to any line of symmetry passing through the centroid of the geometric shape delimited by the edge-termination region, wherein a region of P-type conductivity formed by the doped region and the edge-termination region has a quadrangular shape with rounded corners, said cells being absent at said rounded corners. the doped region has, in top-plan view, a grid-shaped layout delimiting said plurality of cells, each cell has a same geometry among quadrangular, quadrangular with rounded corners and circular, and said ohmic contact (19") extends at said doped region with continuity along the grid-shaped layout, wherein, in said top-plan view, the MPS diode has a layout that is symmetric with respect to any line of symmetry passing through the centroid of the geometric shape delimited by the edge-termination region, wherein a region of P-type conductivity formed by the doped region and the edge-termination region has a quadrangular shape with rounded corners, said cells being absent at said rounded corners.