Patent ID: 7833876

Claim:
A method for manufacturing a semiconductor device comprising: preparing a semiconductor substrate having a main side and a rear side; forming at least one of an active element and a passive element in each of a plurality of element formation regions of the substrate at the main side of the substrate; forming an insulating film over the main side of the substrate; thinning the substrate from the rear side of the substrate; forming a plurality of trenches on the rear side of the substrate after the thinning the substrate, wherein each trench reaches the insulating film; depositing a first insulating material over a sidewall of each trench and over the rear side of the substrate to form a first insulating layer with a first void in the trench, so that the plurality of element formation regions are isolated, wherein the first void is formed in the first insulating layer around a central axis of the trench; and depositing a first conductive material in the first void in each trench and over the rear side of the substrate, wherein the plurality of element formation regions are electrically shielded by fixing a potential of the first conductive material in each trench and over the rear side of the substrate, the element formation regions include a vertical element formation region having a back surface electrode over the rear side of the substrate, in the depositing the first conductive material, a second insulating layer is formed over the first conductive material, in the depositing the first conductive material, a second conductive material for providing the back surface electrode of the vertical element formation region is deposited over the rear side of the substrate, and the second insulating layer is disposed between the first conductive material and the second conductive material.