Deep diode zeners

Claim 1

A deep zener semiconductor diode comprising: a body of single crystal semiconductor material having a first type conductivity, a predetermined level of resistivity, two major opposed surfaces which are, respectively, the top and bottom surfaces thereof, and a vertical axis which is substantially parallel with a first crystal axis of the material of the body; at least one of the major surfaces having a preferred planar crystal orientation which is one selected from the group consisting of (111), (110) and (100); a lamellar structure of a plurality of integral alternate first and second regions of different and opposite type conductivity formed in situ in the body; each region extending between, and terminating in, the opposed major surfaces and having opposed end surfaces, each end surface being coextensive with only one respective major surface; a P-N junction formed by the contiguous surfaces of the material of each pair of abutting regions of opposite type conductivity, the P-N junction being substantially parallel with the first crystal axis and having end portions exposed at the opposed major surfaces; the material of each first region being a portion of the material of the body. the material of each second region consisting of recrystallized semiconductor material of the body formed in situ by the migration of a melt of metal-rich semiconductor material of the body through the entire body from one opposed major surface of the other by thermal gradient zone melting at a predetermined elevated temperature along a thermal gradient substantially parallel with the first preferred crystal axis and the vertical axis of the body and having a predetermined level of concentration of the metal of the melt distributed substantially uniformly throughout the entire region, the level of concentration of the metal being determined by the solid solubility limit of that metal in that semiconductor material at that predetermined elevated temperature of migration, the metal comprising at least one dopant impurity material for inparting the type conductivity and a predetermined level of resistivity to the recrystallized material of the region; a pair of mutually adjacent regions of opposite type conductivity comprising a zener diode; a first electrical contact affixed to, and in an electrically conductive relationship with, the first region of the zener diode; a second electrical contact affixed to, and in an electrically conductive relationship with, the second region of the zener diode, and the predetermined level of resistivity of each of the first and second regions of the zener diode are so arranged that when the P-N junction therebetween is reversed bias to a critical voltage, the P-N junction breaks down by the tunneling of carriers across the depletion zone and results in a high current flow, the occurrence of the breakdown being dependent upon the level of resistivity of the regions of opposite type conductivity and the depletion zone widths which occurs during functioning of the zener diode.