Semiconductor gallium arsenide compatible epitaxial ferroelectric devices for microwave tunable application

Abstract

The presently claimed invention provides a barium strontium titanate/strontium titanate/gallium arsenide (BST/STO/GaAs) heterostructure comprising a gallium arsenide (GaAs) substrate, at least one strontium titanate (STO) layer, and at least one barium strontium titanate (BST) layer. The BST/STO/GaAs heterostructure of the present invention has a good temperature stability, high dielectric constant and low dielectric loss, which enable to fabricate tunable ferroelectric devices. A method for fabricating the BST/STO/GaAs heterostructure is also disclosed in the present invention, which comprises formation of at least one STO layer on the GaAs substrate by a first laser molecular beam epitaxial system, and formation of at least one BST layer on the STO layer by a second laser molecular beam epitaxial system.