Structure and method for forming isolation and buried plate for trench capacitor

A method for fabricating a trench capacitor, comprising the steps of:

• growing an epitaxial layer on a silicon substrate;
• forming a BOX layer above the epitaxial layer;
• forming a SOI layer above the BOX layer;
• depositing a nitride layer above the SOI layer;
• depositing a mask layer above the nitride layer;
• etching a deep trench within the epitaxial layer;
• and
• etching a bounded deep trench isolation moat within the epitaxial layer, wherein the base of the deep trench isolation moat extends into the epitaxial layer, and extends into the silicon substrate, wherein a first N doped region of the epitaxial layer is formed within the bounded deep trench isolation moat, and a second N doped region of the epitaxial layer is formed outside the bounded deep trench isolation moat, wherein the deep trench is within the bounded deep trench isolation moat, and wherein the width of the deep trench isolation moat is at least one order of magnitude larger than the width of the deep trench.