Integrated circuit structure with backside via rail

An IC structure comprising:

• a first transistor comprising a first channel region extending lengthwise along a first direction, a first gate structure extending lengthwise along a second direction different from the first direction, and first source/drain features disposed on opposite sides of the first gate structure;
• a second transistor comprising a second channel region extending lengthwise along the first direction, a second gate structure extending lengthwise along the second direction, and second source/drain features disposed on opposite sides of the second gate structure;
• a dielectric fin disposed between a first one of the first source/drain features and a first one of the second source/drain features;
• a backside via rail extending lengthwise along the first direction and overlapping with the dielectric fin in a third direction different from the first direction and the second direction;
• a first source/drain contact electrically coupled to the first one of the first source/drain features by way of a first silicide layer;
• and
• a second source/drain contact electrically coupled to the first one of the second source/drain features by way of a second silicide layer, wherein the first source/drain contact has a backside surface interfacing the backside via rail, and the dielectric fin has opposite sidewalls respectively interfacing the first one of the first source/drain features and the first one of the second source/drain features.

An IC structure comprising:

• a first transistor comprising a first channel region extending lengthwise along a first direction, a first gate structure extending lengthwise along a second direction different from the first direction, and first source/drain features disposed on opposite sides of the first gate structure;
• a second transistor comprising a second channel region extending lengthwise along the first direction, a second gate structure extending lengthwise along the second direction, and second source/drain features disposed on opposite sides of the second gate structure;
• a dielectric fin disposed between a first one of the first source/drain features and a first one of the second source/drain features;
• a dielectric cap overlapping the dielectric fin in a third direction different from the first direction and the first direction, wherein the dielectric cap has a first sidewall aligned with a first sidewall of the dielectric fin;
• a backside metal structure overlapping the dielectric cap in the third direction;
• and
• a source/drain contact electrically coupled to a first one of the first source/drain features and the backside metal structure, wherein the source/drain contact has a sidewall interfacing the first sidewall of the dielectric cap and the first sidewall of the dielectric fin.