A semiconductor diode comprises a first body of semiconductor material having a selected resistivity and a first type conductivity and a region of second type conductivity and a selected resistivity. The second body consists of recrystallized semiconductor material of a layer thereof having solid solubility of a dopant therein and has the same crystallographic structure as the first body. The second region is formed by a temperature gradient zone melting process embodying the migration of a metal-enriched melt of semiconductor material through the second body of semiconductor material. Preferably, the metal-enriched melt is no greater than approximately 20 microns in thickness. The second body initially has a axial crystallographic orientation when it is a wafer. However, the second body initially may be polycrystalline semiconductor material.