Thin-Film Physical Vapor Deposition System
The Thin-Film Physical Vapor Deposition (PVD) instrument located in Olin 209 is capable of accurately depositing layers of materials ranging from metals, to organic solids, and oxides. The instrument has a central e-beam evaporator in which up to 4 different target materials may be loaded and sequentially evaporated via a pre-defined, computer-controlled recipe. The e-beam allows for fine control ranging from very rapid deposition rates (up to 410 Å/sec) to slower rates of around 1 Å/sec. Continuous and uniform films as thin as 3 nm can be deposited using this method.
In addition, the system includes two thermal evaporators in which resistive element heating evaporates the user-loaded base materials. Both metals and oxides can be successfully evaporated using the thermal evaporators. Also here, the rate of deposition can be accurately controlled.
The instrument also contains two low-temperature evaporators (LTEs) that are particularly useful in depositing organic materials or other materials with lower sublimation temperature. The LTEs are loaded with the base powder and can either sequentially evaporate or both at the same time for a co-deposition, each at independent rates as desired.
The evaporation chamber is accessible via a hinged door in the rear of the machine, which opens to the lab or by a sliding door on the inside of the attached glovebox. With the glovebox, it is possible to conduct sample preparation in an inert, nitrogen environment and load the sample to be coated without exposing it to atmosphere. After it is loaded and the door closed, the process is entirely controlled by user-defined recipes through a touch-screen computer interface. A cryo-pump evacuates the chamber down to base pressures of 10-7 to 10-8 torr within less than two hours. Once the base pressure is reached, the evaporation can be automated with desired thickness, rate, and material properties as defined by the user. Four crystal monitors are arranged within the chamber to measure the rate and accumulated thickness, which are used in the PID controlled feedback loop.
The instrument is accessible to all WFU students, faculty and staff. For more information please contact Dr. Peter Diemer at diempj0@wfu.edu.