Integrated circuits having stacked transistors and backside power nodes

An integrated circuit device comprising:

• a first-type active-region semiconductor structure extending in a first direction;
• a second-type active-region semiconductor structure extending in the first direction and stacked with the first-type active-region semiconductor structure;
• a front-side power rail in a front-side conductive layer above the first-type active-region semiconductor structure and the second-type active-region semiconductor structure, wherein the front-side power rail extends in the first direction and is configured to maintain a first supply voltage;
• a plurality of back-side power rails in a back-side conductive layer below the first-type active-region semiconductor structure and the second-type active-region semiconductor structure, wherein each of the back-side power rails extends in the first direction and at least one of the back-side power rails is configured to maintain a second supply voltage;
• a first source conductive segment intersecting the first-type active-region semiconductor structure at a source region of a first-type transistor, and the first source conductive segment conductively connected to the front-side power rail through a front-side terminal via-connector;
• a back-side power node in the back-side conductive layer extending in the first direction;
• and
• a top-to-bottom via-connector between the first source conductive segment and the back-side power node, wherein the back-side power node is conductively connected to the first source conductive segment through the top-to-bottom via-connector.

An integrated circuit device comprising:

• a first-type active-region semiconductor structure;
• a second-type active-region semiconductor structure below the second-type active-region semiconductor structure;
• a front-side power rail extending in a first direction above the first-type active-region semiconductor structure and configured to maintain a first supply voltage;
• a conductive segment intersecting the first-type active-region semiconductor structure;
• a front-side terminal via-connector connected between the conductive segment and the front-side power rail;
• a back-side power node extending in the first direction in a back-side conductive layer below the second-type active-region semiconductor structure;
• a top-to-bottom via-connector connected between the conductive segment and the back-side power node;
• and
• a back-side power rail extending in the first direction in the back-side conductive layer and configured to maintain a second supply voltage.