1. What determines the coating uniformity?
Considering circular magnetrons the film thickness distribution on the substrate depends on the coating flux distribution from the target surface. This flux distribution is mainly influenced by the given setup and geometry, as the target diameter relative to the substrate size and target to substrate distance will influence the film thickness distribution. In static coating situation generally the target diameter needs to be larger than the substrate diameter. Reducing the target to substrate distance will minimize deviations in the film thickness distribution, however, lowering the deposition rate.
THIN FILM CONSULTING offers several IONIX® sputtering sources with a quick coupling feedtrough that can be used to adjust the target-to-substrate distance for highvacuum applications or with a z-shift for ultrahigh vacuum applications without breaking the vacuum inside the chamber.
2. What is confocal sputtering?
If co-deposition of thin films and/or several different target materials need to be deposited on a single substrate confocal sputtering can be used. Utilizing this technique the sputtering source is tilted off normal and directed to a focal point on a rotating substrate. Due to the rotation of the substrate excellent film thickness uniformity is achievable with source smaller than the substrate diameter. Typically substrates as big as twice the target diameter can be coated in this fashion.
THIN FILM CONSULTING offers several IONIX® sputtering sources in the range of 2'' - 6'' (Ø50 - 152.4 mm) that can be used in a confocal arrangement. These sputtering sources feature cross-contamination chimneys and manual or pneumatic shutters, tilts(exsitu/insitu) to vary the incident angle. In addition a quick coupling feedtrough can be used to adjust the target-to-substrate distance for highvacuum application or a z-shift for ultrahigh vacuum applications without breaking the vacuum inside the chamber.