Patent ID: 7821066
Filing Date: 2010-10-26
Classification: H01L

Abstract:
1. A fully depleted MOSFET comprising: an SOI structure including a single crystal substrate material, a BOX positioned on the substrate material, and a single crystal active layer epitaxially grown on the BOX; the BOX including a first insulating layer of single crystal rare earth insulator material with a first dielectric constant and a first thickness and a second insulating layer having a second dielectric constant different than the first dielectric constant and a second thickness different than the first thickness; drain and source regions formed in the single crystal active layer so as to be separated by a fully depleted channel region in the single crystal active layer; and a gate insulating layer overlying the channel region and a gate stack positioned on the gate insulating layer, wherein the second insulating layer is formed between the first insulating layer and the single crystal active layer after the epitaxial growth of the single crystal active layer, and the second insulating layer comprises at least silicon and oxygen; and wherein the first insulating layer is derived from a single crystal layer formed of a rare earth oxide material ReO