Epitaxial refractory-metal buer layers with a chemical gradient for adjustable lattice parameter and controlled chemical interface

TL;DR

This paper presents the development of nanometer-thick epitaxial (V,Nb) alloy layers with a compositional gradient on sapphire, topped with a W layer, enabling rapid exploration of strain-dependent properties.

Contribution

It introduces a novel method for creating epitaxial layers with a continuous compositional gradient for combinatorial material studies.

Findings

Successful fabrication of (V,Nb) gradient layers on sapphire.

Effective pseudomorphic W capping layer for property investigation.

Potential for rapid screening of strain-dependent phenomena.

Abstract

We have developed and characterized the structure and composition of nanometers-thick solid-solution epitaxial layers of (V,Nb) on sapphire (1120), displaying a continuous lateral gradient of composition from one to another pure element. Further covered with an ultrathin pseudomorphic layer of W, these provide a template for the fast combinatorial investigation of any growth or physical property depending of strain.