Patent ID: 8946050
Filing Date: 2015-02-03
Classification: H01L

Abstract:
1. A method of comprising: forming a plurality of deep trenches having a first depth in a silicon substrate; forming a deep n-well or deep p-well around a bottom of each of the plurality of deep trenches; filling the plurality of deep trenches with a first oxide; forming a first or second shallow trench between each pair of adjacent deep trenches, each first and second shallow trench having a second depth less than the first depth; forming a first p-well or first n-well, respectively, above each deep n-well or p-well; forming a second n-well at a bottom of each first shallow trench; filling the first shallow trenches with a second oxide; forming a second p-well at a bottom of each second shallow trench; filling the second shallow trenches with the second oxide; forming a p+ region above each second n-well on each side of each first shallow trench; and forming an n+ region above each second p-well on each side of each second shallow trench.