Through-substrate via and method for forming the same

A method comprising:

• forming a stack of nanostructures over a substrate;
• forming an epitaxial source/drain region adjacent the stack of nanostructures;
• forming a dummy gate structure over the stack of nanostructures;
• forming a first recess extending through the dummy gate structure and the stack of nanostructures, wherein the recess extends deeper than the epitaxial source/drain region;
• filling the first recess with a dielectric material;
• forming a second recess extending through the epitaxial source/drain region and the dielectric material;
• and
• filling the second recess with a conductive material.

A structure comprising:

• a plurality of epitaxial regions on a substrate;
• a plurality of isolation regions extending into the substrate, wherein the isolation regions of the plurality of isolation regions are respectively sandwiched between neighboring epitaxial regions of the plurality of epitaxial regions;
• a plurality of dielectric layers over the plurality of epitaxial regions and over the plurality of isolation regions;
• and
• a through via extending through the plurality of dielectric layers and into the substrate, wherein the through via is encircled by the plurality of epitaxial regions and the plurality of isolation regions.