Thin‐Film Formation Techniques

Abstract

Abstract Thin films are commonly utilized in industries such as electronics, packaging, decoration, and protection. The two primary techniques for thin‐film deposition include physical vapor deposition (PVD) and chemical vapor deposition (CVD). The selection and application of a particular technique depends on the desired properties of thin films. For example, for electronic applications where via filling is a requirement, preference is for the CVD process where gaseous precursor finds its way to all spaces, forming a uniform thin film on the whole topography. PVD techniques have limitation that the substrate surface has to be in the line of sight of the incoming flux. Contoured surfaces require special source and substrate manipulation for conformal coatings. Likewise, where large flat surface area coverage is needed, like thin films on decorative window glass, a simpler process such as PVD, both as evaporation and sputtering, is preferred over CVD. This article describes PVD and CVD techniques and their multiple variants. PVD processes, evaporation, sputtering, and pulsed laser deposition (PLD) with their variants, ion plating and high‐power impulse magnetron sputtering (HIPIMS), form the first part of the article, whereas the second part contains descriptions of CVD processes, including metalorganic chemical vapor deposition (MOCVD) and plasma‐assisted (or enhanced) chemical vapor deposition (PACVD). Notably absent in this article are molecular beam epitaxy (MBE), a PVD process and atomic layer epitaxy (ALE), a CVD process. These are very controlled deposition processes and require sophisticated control hardware. It is this sophistication that requires MBE and ALD to be dealt separately and, therefore, not included in this article.