Toward controlled ultra-high vacuum chemical vapor deposition processes

How will we push our thin film performances to new heights? This is one of the central questions for researchers in this field. The functionality of the thin films is key to the performance of many of our components, which are used in products ranging from cameras and cars to satellites. Our goal is to produce these components with exactly the desired properties for the job at hand. One of the methods for achieving this is by increasing the purity of the film, through a reduction of unwanted molecular structures in the thin film layer. This effort is comparable to building a bridge with a desired stiffness. Applying unintended materials or constructions will change the stiffness properties of the bridge and make the job very difficult. For thin films, this has to be done at nanoscale level, where a small amount of misplaced molecules can already cause a noticeable performance difference. In our work, we present methods to build desired structures with the highest attainable purity. Problems that arise in trying to achieve this are related to how well we can construct the thin film that we want, while we operate in the circumstances that allow for the highest purity. To solve some of these problems, we have implemented a measurement apparatus that allows us to more accurately select the building blocks for the thin films. In doing so, we are apparently the first to actively control atomic partial pressure levels in an ultra-high vacuum environment through feedback.