Gate all around structure with additional silicon layer and method for forming the same

A semiconductor structure, comprising:

• a substrate;
• channel layers vertically stacked over the substrate in a first direction;
• a first dielectric fin structure formed at a first side of the channel layers and longitudinally oriented along a second direction different from the first direction;
• a second dielectric fin structure formed at a first side of the channel layers and longitudinally oriented along the second direction;
• a gate structure wrapping around the channel layers and longitudinally oriented along a third direction different from the first direction and the second direction;
• a source/drain structure attached to the channel layers and sandwiched between the first dielectric fin structure and the second dielectric fin structure;
• and
• a Si layer having a first portion sandwiched between the first dielectric fin structure and the source/drain structure and a second portion sandwiched between the second dielectric fin structure and the source/drain structure.

A semiconductor structure, comprising:

• first channel layers stacked along a first direction;
• second channel layers stacked along the first direction;
• a first source/drain structure attaching to the first channel layers;
• a second source/drain structure attaching to the second channel layers;
• a dielectric feature formed between the first source/drain structure and the second source/drain structure and extending along a second direction different from the first direction;
• a Si layer formed over the first source/drain structure;
• and
• a first contact formed over the first source/drain structure and in direct contact with the Si layer.