| abstract |
In a method, a first dielectric layer is formed over semiconductor fins, a second dielectric layer is formed over the first dielectric layer, the second dielectric layer is recessed below a top of each of the semiconductor fins, a third dielectric layer is formed over the recessed second dielectric layer, and the third dielectric layer is recessed below the top of the semiconductor fin, thereby forming a wall fin. The wall fin includes the recessed third dielectric layer and the recessed second dielectric layer disposed over the recessed third dielectric layer. The first dielectric layer is recessed below a top of the wall fin, a fin liner layer is formed, the fin liner layer is recessed and the semiconductor fins are recessed, and source/drain epitaxial layers are formed over the recessed semiconductor fins, respectively. The source/drain epitaxial layers are separated by the wall fin from each other. |