Transistor structure with multiple halo implants having epitaxial layer, high-k dielectric and metal gate

Abstract

A method can include ion implanting with the gate mask to form first halo regions and ion implanting with the gate mask and first spacers as a mask to form second halo regions. The gate mask and first spacers can be removed, and an epitaxial layer formed. A dummy gate mask can be formed. Ion implanting with the dummy gate mask can from source-drain extensions. Second spacers can be formed on sides of the dummy gate mask. Ion implanting with the dummy gate mask and second spacers as a mask can form source and drain regions. A surface dielectric layer can be formed and planarized to expose a top of the dummy gate. The dummy gate can be removed to form gate openings between the second spacers. A hi-K dielectric layer and at least two gate metal layers within the gate opening. Related devices are also disclosed.