Some circuit applications use NDMOS devices for level shifting and/or output switches. Typically, these circuit applications require high voltage, low charge storage diodes. An example of such a circuit application is a half bridge driver 100 having a diode 110, as shown in FIG. 1. Conventional diode 110 used in the half bridge driver 100 is a Schottky diode with a quasi-vertical structure. The quasi-vertical Schottky diode includes a silicide anode, an N− island cathode with an N+ buried layer, and an N+ sinker. As a result of its structure, the quasi-vertical Schottky diode requires a different epi thickness and resistivity for differing voltages to maintain near optimum specific on resistance.
Moreover, conventional diodes made with a N epi layer as a cathode, an N+ buried layer, and an N+ sinker are not compatible with current process flows useful to make lateral drain extension NDMOS structures.
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