<P> A thin film is a layer of material ranging from fractions of a nanometer ( monolayer ) to several micrometers in thickness . The controlled synthesis of materials as thin films ( a process referred to as deposition ) is a fundamental step in many applications . A familiar example is the household mirror , which typically has a thin metal coating on the back of a sheet of glass to form a reflective interface . The process of silvering was once commonly used to produce mirrors , while more recently the metal layer is deposited using techniques such as sputtering . Advances in thin film deposition techniques during the 20th century have enabled a wide range of technological breakthroughs in areas such as magnetic recording media , electronic semiconductor devices , LEDs , optical coatings ( such as antireflective coatings ) , hard coatings on cutting tools , and for both energy generation ( e.g. thin - film solar cells ) and storage ( thin - film batteries ) . It is also being applied to pharmaceuticals , via thin - film drug delivery . A stack of thin films is called a multilayer . </P>
what is meant by thin film in physics
a layer of material ranging from fractions of a nanometer ( monolayer ) to several micrometers in thickness