Patent ID: 8890244
Filing Date: 2014-11-18
Classification: H01L

Abstract:
1. A semiconductor structure, comprising: a substrate of a P-type material; a high-voltage well disposed in the substrate of a N-type material; an element having a source area and a drain area disposed in the high-voltage well; a top region of the P-type material disposed in, and separated from the source and drain areas by, the high-voltage well; a grade region of the N-type material disposed on the top region; the structure has a circular topography disposed about a center; a first section comprises a first plurality of disjoined slices defined by a first set of circular arcs; a second section comprises a second plurality of disjoined slices defined by a second set of circular arcs; and one or more slices of the first section alternate with one or more slices of the second section; first and second P-wells having an annular shape and disposed in a surface of an outer portion of the N-well and in the substrate outside of and adjacent to the N-well, respectively; the P-top region has a shape of an annular ring and is encircled by the first P-well, and the N-grade region has an annular shape, the structure further comprising: an N-type drain having an annular shape and disposed in an annular portion of the surface of the N-well and encircled by the P-top region; a source including annular N-type and P-type respective inner and outer regions disposed in a surface of the first P-well; and a P-type bulk region having an annular shape and disposed in a portion of a surface of the second P-well.