Aluminum Silicate Films Obtained by Low‐Pressure Metal‐Organic Chemical Vapor Deposition

Abstract

Amorphous alumina‐silica films with film thickness of 0.41–2.69 μm were prepared on glass and silicon substrates by metal‐organic chemical vapor deposition using a mixture of aluminum tri‐sec‐butoxide (ATSB), hexamethyldisilazane (HMDSN), and argon. By controlling the inputs of ATSB and HMDSN, alumina‐silica thin films could contain varied compositions and adjustable properties. Basically, the codeposition of alumina and silica to form alumina‐silica using ATSB and HMDSN had a faster growth rate than their individual components. The internal stress could be adjusted by deposition temperature and reactant inputs. Adhesion could be improved by having a silicon‐rich thin film, whereas an aluminum‐rich film could have slightly higher hardness. Optical properties, e.g., refractive index and optical transmittance, were also measured.