Patent ID: 7700405

Claim:
A method for constructing a microelectronic assembly comprising: forming first and second semiconductor devices over a substrate having a first dopant type at a first concentration; forming first and second buried regions having a second dopant type respectively below the first and second semiconductor devices with a gap therebetween, the first and second buried regions each having first ends adjacent to the gap and second ends opposing the gap, the first ends extending a first depth from the first and second semiconductor devices; forming an epitaxial layer having the first dopant type over the substrate; forming at least one well region over the substrate and between the first and second semiconductor devices; and forming a barrier region having the first dopant type at a second concentration between and adjacent to the first ends of the first and second buried regions such that at least a portion of the barrier region extends a second depth from the first and second semiconductor devices, the second concentration being greater than the first concentration and the second depth being greater than or equal to the first depth.