Source and drain EPI protective spacer during single diffusion break formation

A method for forming single diffusion break (SDB) without damaging source and drain epitaxial growth regions, the method comprising:

• forming the source and drain epitaxial growth regions between sacrificial gates, the sacrificial gates formed over a plurality of fins, wherein a top surface of the source and drain epitaxial growth regions extends above a bottom surface of the sacrificial gates;
• performing SDB patterning;
• removing at least one of the sacrificial gates to expose the plurality of fins such that top surfaces of shallow trench isolation (STI) regions are exposed, the STI regions formed between the plurality of fins;
• anisotropically etching the plurality of fins to create a first opening in a first etch process, the anisotropic etching resulting in remaining fin portions, and the first etch process completed once the top surfaces of the STI regions are reached;
• forming inner spacers within the first opening;
• removing the remaining fin portions to create a second opening in a second etch process, the second etch process completed once bottom surfaces of the STI regions are reached;
• and
• isotropically etching the second opening in a third etch process in a lateral direction with respect to the source and drain epitaxial growth regions to increase SDB width.

A semiconductor structure for forming single diffusion break (SDB) without damaging source and drain epitaxial growth regions, the semiconductor structure comprising:

• the source and drain epitaxial growth regions disposed in direct contact with a substrate, wherein a top surface of the source and drain epitaxial growth regions extends above a bottom surface of sacrificial gates;
• a conductive material disposed over the source and drain epitaxial regions;
• inner spacers disposed between source and drain epitaxial regions;
• a dielectric material disposed between the inner spacers and disposed between STI regions, the STI regions disposed between the substrate and the inner spacers, and at least one of the STI regions directly contacting a bottom surface of the inner spacers;
• and
• an air gap defined within a distal end of the dielectric material.