Ultra Vacuum System

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An ultra vacuum system (really, an ultra-high vacuum system, or UHV system) contains a specific set of components designed to create, measure, and maintain extremely low pressures—below 10−710^{-7} Pa or 10−910^{-9} Torr.

Here’s a breakdown of what a typical UHV system contains:

• Made of stainless steel (usually 304L or 316L).
   
• Welded or sealed with metal gaskets (like copper) to avoid leaks.
   
• Polished inside surfaces to reduce outgassing.
   

• ConFlat (CF) flanges with copper gaskets are standard.
   
• These ensure metal-to-metal, leak-tight seals.
   

• Heaters (often flexible jackets) used to bake the chamber to 100–250 °C.
   
• Baking drives out adsorbed gases (mainly water vapor) to reach UHV.
   

• Typically a combination of pumps, including:
   
  • Roughing pump (rotary vane or scroll pump) – brings pressure down to ~10⁻² Torr.
     
  • Turbo-molecular pump (TMP) – takes it lower (~10⁻⁸ Torr).
     
  • Ion pump – maintains pressures down to 10⁻¹¹ Torr.
     
  • Cryopump or Getter pump – for trapping specific gases (H₂, CO, etc.).
     

• Pirani gauge – for higher vacuum ranges (not UHV).
   
• Cold cathode or Penning gauge – good down to ~10⁻⁹ Torr.
   
• Ionization gauge (hot filament) – for true UHV measurements.
   

• Electrical feedthroughs let you power heaters, sensors, or electron guns inside the vacuum without breaking the seal.
   
• Also includes optical windows, manipulators, and mechanical feedthroughs for moving parts inside.
   

• Pressure controllers, interlocks, temperature monitoring, and data logging.
   

• Sample holders, stages, manipulators
   
• Mass spectrometers
   
• Electron or ion guns
   
• X-ray sources
   
• Cryostats or cooling systems