Atomic Hydrogen Source (HCL)

Atomic Hydrogen Source (HCL)

Atomic hydrogen is very reactive and it allows the cleaning of various substrates like gallium arsenide, indium phosphide, etc. at low temperatures. In addition it can be also used for surfactant growth of epitaxial layers. Molecular hydrogen gas flows through a molybdenum tube passing a hot tungsten filament which is located at the end of this tube and which is heated up to 2500 °C. By this an excellent cracking efficiency of molecular into atomic hydrogen is achieved. Using a high precision valve the hydrogen gas pressure can be directly adjusted. Moreover, with a mass flow controller which is mounted between the hydrogen gas bottle and the leak valve a very accurate pressure control is possible.


Heating systemRadiation heating
Temperature range200°C … 2500°C
Temperature stability0.1 K (depending on the PID controller)
Max. outgas temp.2500°C
Max. power280W (NW 40 CF)
Max. current25A
Bakeout temperature250°C
ConditioningHeat to maximum temperature with or without crucible
ShippingUHV cleaned, in stainless steel container with valve

Standard Configuration

  • Flange size: CF40 / CF63
  • Max outer diameter: 38mm or to your specification
  • Length: 180mm ... 300mm , or to your specification
  • Heating system: Tungsten filament
  • Thermocouple: Type C or to your specification


  • Molybdenum version
  • Tungsten version
  • Mass flow controller

Looking for a custom solution? No problem - let us know and we will work with you.