High-dielectric constant oxides on semiconductors using a Ge buffer layer

Abstract

Abstract This is a method for fabricating a structure useful in semiconductor circuitry. The method comprises: growing a germanium layer 28 directly or indirectly on a semiconductor substrate 20; and depositing a high-dielectric constant oxide 32 (e.g. a ferroelectric oxide) on the germanium layer. Preferably, the germanium layer is epitaxially grown on the semiconductor substrate. This is also a semiconductor structure, comprising: a semiconductor substrate; a germanium layer on the semiconductor substrate; and a high-dielectric constant oxide on the germanium layer. Preferably the germanium layer is single-crystal. Preferably the substrate is silicon and the germanium layer is less than about 1 nm thick or the substrate is gallium arsenide (in which case the thickness of the germanium layer is not as important). A second germanium layer 40 may be grown on top of the high-dielectric constant oxide and a conducting layer 42 (possibly epitaxial) grown on the second germanium layer. Preferably the high-dielectric constant oxide is a titanate, such as barium strontium titanate. When the high-dielectric constant oxide is a lead-containing titanate 34, a buffer layer of non-lead-containing titanate 32 is preferably utilized between the germanium layer and the lead-containing titanate.

Inventors

• 👤 Scott R. Summerfelt

Bibliographic Details