Technical Overview HGS Chamber Processing
This page is a review of the fundamental physics associated with the use of HGS®. Please refer to our Successful HGS® Implementation for recommended steps for implementing HGS® at your facility.

Traditional Chamber Processing

The traditional industry method of removing moisture from the inside of a process chamber (See figure 1) has been to apply heat via custom heating blankets, heat tape, or internal radiant heaters, while also pumping on the chamber until the desired base pressure is obtained. This method, which slowly desorbs molecular water from the chamber walls, transports the water molecules via random molecular flow to the inlet of the vacuum pump. Random molecular flow by its nature allows water molecules and particulate to bounce around the chamber randomly until they eventually find the pump inlet. Random molecular flow occurs when the vacuum system lacks a transport medium to carry water molecules and particulate out of the chamber after they have been freed from the chamber walls. This process of bake out is well documented as requiring hours, and in some cases days, to evacuate and qualify a chamber for processing.
Figure 1

HGS Chamber Processing
HGS® technology quickly removes moister and particulate from chamber walls by applying heat and kinetic energy directly to the inside of the chamber, while also providing a transport medium for removal of contaminants. This technology uses three features.
  • The Low Pressure HGS® Mode heats the inside chamber surfaces via a hot viscous gas flow, thereby freeing moisture and particles from the inside surfaces, entraining them in the viscous flow, and sweeping them out of the chamber.
  • The Low Pressure HGS® Mode operates within a programmed upper and lower temperature band while gently pulsing the chamber via pressure oscillations, thus further dislodging moisture and particulate and entraining them into the viscous gas stream.
  • The CFP Mode cools the inside surfaces of the chamber to ambient temperature while maintaining viscous flow and sweeping out residual contaminates.


Figure 2

Click here to view a HOT Gas Animation
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View the Hot Gas Animation.