Embedded bottom metal contact formed by a self-aligned contact process for vertical transistors
Embodiments are directed to a method and resulting structures for a vertical field effect transistor (VFET) having an embedded bottom metal contact. A semiconductor fin is formed on a doped region of a substrate. A portion of the doped region adjacent to the semiconductor fin is recessed and an embedded contact is formed on the recessed portion. A material of the conductive rail is selected such that a conductivity of the embedded contact is higher than a conductivity of the doped region.
1. A semiconductor device, comprising:
a semiconductor fin on a doped region of a substrate; and
an embedded bottom contact formed on a recessed portion of the doped region along three sides of the semiconductor fin;
wherein a conductivity of the embedded bottom contact is higher than a conductivity of the doped region.
2. The semiconductor device of claim 1 , wherein the embedded bottom contact comprises a thickness of about 7 to about 12 nm.
3. A semiconductor device, comprising:
a semiconductor fin on a doped region of a substrate;
a conductive gate formed over a channel region of the semiconductor fin;
a bottom spacer between the conductive gate and the doped region;
a conductive rail on a recessed portion of the doped region;
a dielectric layer between the conductive rail and the conductive gate;
a first conductive contact on a surface of the conductive rail; and
a second conductive contact on a surface of the semiconductor fin;
wherein a conductivity of the conductive rail is higher than a conductivity of the doped region.
4. The semiconductor device of claim 1 , wherein the embedded bottom contact is recessed about 3 to about 5 nm below the bottom spacer.