Silicon dioxide, SiO2, is one of the preferred low index materials for optical thin film technology. It is often deposited by electron beam evaporation source with less porosity and scattering, relatively durable and can have a good laser damage threshold. Beside these advantages the deposition of critical optical thin film stacks with silicon dioxide from an E-gun was severely limited by the stability of the evaporation pattern or angular distribution of the material. The even surface of SiO2 granules in crucible will tend to develop into groove and become deeper with the evaporation process. As the results, angular distribution of the evaporation vapor changes in non-predicted manner. This report presents our experiments to apply Ion Assisted Deposition process to evaporate silicon in a molten liquid form. By choosing appropriate process parameters we can get SiO2 film with good and stable property.
Due to high conductivity, silver coating is often used as high reflectivity mirror in optical and in microwave spectrum area. The thickness of silver film in optical application is usually less than the one used in microwave range. Thin silver coating has been successfully deposited by thermal evaporation. Meanwhile thick silver film of tens micrometer is often made by electrochemical process.
DC magnetron is well known as good method for depositing metallic coating. Here we present an attempt to apply DC magnetron sputtering for depositing thick silver mirror. Results show that coating made by this method meet well the requirements in microwave range.