Semiconductor device with isolation structure and method of manufacturing the same

A semiconductor device, comprising:

• a first semiconductive region;
• a second semiconductive region;
• an isolation structure formed between the first semiconductive region and the second semiconductive region and comprising:
• an isolation bottom formed beneath the second semiconductive region;
• and
• an isolation ring having a lower portion connecting the isolation bottom and an upper portion surrounding the second semiconductive region;
• and
• a via array comprising a plurality of inner via formed in the second semiconductive region, on the isolation bottom and surrounded by the isolation structure,
• wherein the isolation structure and the plurality of inner vias have insulating materials, and
• wherein each of the plurality of inner via has a top and a bottom and an area of the top is larger than that of the bottom.

A method for manufacturing a semiconductor device, comprising:

• forming an embedded doped region in a substrate;
• and
• forming an isolation ring and at least one inner via in the substrate,
• wherein forming the isolation ring comprises:
• forming a plurality of first insulating vias and an isolation bottom by etching a plurality of first trenches and a lateral tunnel in the substrate;
• and filling the plurality of first trenches and the lateral tunnel with insulating materials;
• and
• forming a plurality of second insulating vias by etching a plurality of second trenches in the substrate between the plurality of first insulating vias;
• and filling the plurality of second trenches with insulating materials,
• wherein the isolation ring and the isolation bottom separating the substrate into a first semiconductive region and a second semiconductive region, and
• wherein the second semiconductive region is surrounded by the isolation ring.