International Business Machines Corporation
Field-Effect Transistor Devices with Sidewall Implant Under Bottom Dielectric Isolation

Abstract:

FET devices with bottom dielectric isolation and sidewall implants in the source and drain regions to prevent epitaxial growth below the bottom dielectric isolation are provided. In one aspect, a semiconductor FET device includes: a device stack(s) disposed on a substrate, wherein the device stack(s) includes active layers oriented vertically over a bottom dielectric isolation layer; STI regions embedded in the substrate at a base of the device stack(s), wherein a top surface of the STI regions is recessed below a top surface of the substrate exposing substrate sidewalls under the bottom dielectric isolation region, wherein the sidewalls of the substrate include implanted ions; source and drains on opposite sides of the active layers; and gates surrounding a portion of each of the active layers, wherein the gates are offset from the source and drains by inner spacers. A method of forming a semiconductor FET device is also provided.