Restgasen
Restgasen, or residual gases, are the gases that remain in a vacuum system after evacuation. They arise from outgassing of chamber walls and components, desorption of adsorbed molecules, and small leaks or vapors from seals, pumps, and lubricants. In high or ultra-high vacuum, the restgas is governed by a balance between pumping speed and the rate at which surfaces desorb or release gases.
The composition of restgasen varies with material, temperature, and cleanliness. Common components include hydrogen (H2), water
Restgasen are routinely monitored using a residual gas analyzer (RGA), a mass spectrometer that identifies gases
In experiments, restgasen can influence surface chemistry, cause film deposition, affect contamination of samples, and interfere