High voltage deep diode power semiconductor switch

Claim 1

A semiconductor switch comprising a body of semiconductor material having two major opposed surfaces forming respectively the top and bottom surfaces of the body, a predetermined level of resistivity, a predetermined type conductivity, a preferred crystal structure and a vertical axis substantially perpendicular to the major opposed surfaces; at least one of the major surfaces having a predetermined crystal planar orientation; at least one group of four planar regions of alternate and opposite type conductivity and a P-N junction formed by the abutting and contiguous surfaces of each pair of regions of opposite type conductivity disposed in the body and so arranged that the P-N junctions and planar regions are substantially perpendicular to, and terminate in, the major opposed surfaces of the body; the material of at least three of the four planar regions consisting of recrystallized semiconductor material of the body; the recrystallized material of the at least three planar regions having been formed by the migration of a melt of metal-rich semiconductor material through the material of the body by thermal gradient zone melting at a predetermined elevated temperature along a thermal gradient which has a predetermined crystal axis orientation which is substantially parallel to the vertical axis of the body; the recrystallized material of each of the at least three regions having a substantially uniform level of concentration of the metal migrated through the body throughout the entire region as determined by the solid solubility of that metal in that semiconductor material at that predetermined elevated temperature of migration; the metal containing at least one material for imparting a predetermined level of resistivity and a predetermined type conductivity to its respective planar region; each of the first and third regions having the same type conductivity as that of the body; each of the first and third regions having a different level of resistivity from each other; each of the second and fourth regions having a second and opposite type conductivity than the first and second regions and a different level of resistivity from each other; each of the three regions of recrystallized semiconductor material having a preferred crystal direction; a first electrical contact affixed in an electrical conductive relationship to the first region of the group, and a second electrical contact affixed in an electrical conductive relationship to the fourth region of the group.