Substrate Selection for Thin-Film Growth

Abstract

Although it is an integral part of any structure involving a film, the substrate is often taken for granted. The choice of substrate is, however, one of the most important materials issues in thin-film growth. This article focuses on substrates for thin films and will provide criteria for selecting the proper material needed to fill specific application requirements. As will become obvious, the ideal substrate for a given film often does not exist. Specific applications require different substrate materials that offer an acceptable compromise for the purpose at hand. Ideally, the substrate should give mechanical support but not interact with the film except to provide sufficient adhesion, and in many cases, the provision of a template for atomic ordering. In practice, however, the substrate exerts considerable influence on film characteristics. The search for viable substrate materials is an active area of research.