Model VAF    Vacuum Anneal Furnace Systems

The Model VAF Furnace System is designed by RCH Associates to perform annealing, alloying or sintering of substrate films that are sensitive to residual oxidation such as refractory and composite metals.


The system includes a moving element that traveses the outside of the main vacuum process chamber.


The components of the processing system generally include:


  • Main quartz process tube with vacuum flange at the load port. The flange includes a line that is connected to a vacuum pump and a gas injection port.
  • An inert, noble or forming gas delivery system.
  • A fast response element that is mounted to a guide track, liner bearing system that is motor driven.
  • An array of fans to cool the outer wall of the main chamber tube.
  • A pumping system that includes 2 isolation valves. One valve is used to isolate the chamber from the vacuum pump to allow high flows of purge gas during cooling. The second valve allows the vacuum pump to evacuate the chamber.   


The process steps for a typical vacuum annealing process are:


  • With the element retracted from covering the main chamber, the substrates are then inserted. This allows the substrates to be loaded at room ambient temperature.
  • The main chamber is sealed and vacuum is drawn to evacuate all residual oxygen from the process environment and to outgas any residuals.
  • The element, which is preheated, then traveses to cover the main chamber and raise the temperature of the substrates to annealing targets. Substrates remain at-temperature for the designated time.
  • After timed-annealing, the element traverses to uncover the main chamber.
  • When the element is retracting, the fans are turned on to air-cool the outer wall of the chamber tube. Simultaneoulsy, a high volume of gas is delivered to the inside of the chamber to cool the substrates. The combination of these methods rapidly returns the substrates to room ambient temperature.
  • The substrates are then retracted from the main chamber.


VAF Furnace Systems may include a load station with cantilever loaders or it may be loaded manually.


The system is completely programmed, operated and monitored by the ASTRA Control System.