Systems and methods for integrated circuits comprising multiple body biasing domains

A method comprising:

• forming an epitaxy layer of a first conductivity type on a semiconductor substrate of the first conductivity type;
• forming in the epitaxy layer a wall structure of a second conductivity type around a first region;
• electrically isolating the first region from a second region in the epitaxy layer, wherein said electrically isolating includes:
• forming in the epitaxy layer a bottom buried structure of the second conductivity type under the first region, and
• connecting the bottom buried structure to the wall structure;
• and
• forming in the first and second regions a first plurality of transistors of the first conductivity type and a second plurality of transistors of the second conductivity type.

A method comprising:

• forming an epitaxy layer of a first conductivity type on a semiconductor substrate of the first conductivity type;
• forming in the epitaxy layer a first wall structure of a second conductivity type around a first region and a second wall structure of the second conductivity type around a second region;
• and
• electrically isolating the first region from the second region, wherein said electrically isolating includes:
• forming in the epitaxy layer a first bottom buried structure of the second conductivity type under the first region and a second bottom buried structure of the second conductivity type under the second region, and
• connecting the first and second bottom buried structures to the first and second wall structures, respectively.