Methods of atomic-layer deposition of hafnium oxide/erbium oxide bi-layer as advanced gate dielectrics

摘要

Provided is a two-step ALD deposition process for forming a gate dielectric involving an erbium oxide layer deposition followed by a hafnium oxide layer deposition. Hafnium oxide can provide a high dielectric constant, high density, large bandgap and good thermal stability. Erbium oxide can act as a barrier against oxygen diffusion, which can lead to increasing an effective oxide thickness of the gate dielectric and preventing hafnium-silicon reactions that may lead to higher leakage current.

主权项

1. A semiconductor device, comprising
a silicon-containing substrate; a gate dielectric layer, wherein the gate dielectric layer comprises a first sub-layer formed above the substrate and a second sub-layer formed above the first sub-layer, wherein the first sub-layer consists of erbium oxide, and the second sub-layer comprises hafnium oxide; and a gate electrode formed above the gate dielectric layer.