Isolation Structure for for Isolating Epitaxially Grown Source/Drain Regions and Method of Fabrication Thereof

A method, comprising:

• epitaxially growing a first source/drain structure and a second source/drain structure over a substrate;
• forming a first material layer over the first source/drain structure and the second source/drain structure;
• after the forming the first material layer, performing a gate replacement process;
• after the performing the gate replacement process, replacing the first material layer with a second material layer;
• etching an opening that extends vertically through the second material layer, wherein the opening is formed between the first source/drain structure and the second source/drain structure;
• filling the opening with a third material layer;
• and
• replacing the second material layer with source/drain contacts.

A method, comprising:

• providing a dummy gate, a first source/drain and a second source/drain, wherein the first source/drain and the second source/drain merge into each other;
• forming an etching-stop layer over the first source/drain and the second source/drain;
• forming a semiconductor layer over the etching-stop layer;
• replacing the dummy gate with a metal-containing gate after the semiconductor layer has been formed;
• etching away the semiconductor layer after the dummy gate has been replaced, wherein the etching-stop layer prevents the first source/drain and the second source/drain from being etched away;
• forming a carbon-containing layer over the first source/drain and the second source/drain after the semiconductor layer has been etched away;
• etching an opening that extends through the carbon-containing layer, wherein the opening separates the first source/drain from the second source/drain;
• filling the opening with a dielectric layer;
• removing the carbon-containing layer and the etching-stop layer without substantially removing the dielectric layer and the first source/drain and the second source/drain;
• and
• forming source/drain contacts on top surfaces and side surfaces of the first source/drain and the second source/drain.