Measurement of absolute radical densities using line-of-sight threshold ionization mass spectrometry (LOS-TIMS) was discussed. The O, O 2 and Ar densities and the average neutral-gas temperature in an O 2/Ar electrical discharge were measured as a function of pressure in the plasma chamber. Collisions within the molecular beam extracted from the discharge was also studied for higher plasma chamber pressures. It was found that the O atom density increases with pressure and O 2 mole fraction in the feed gas and is in the range of 2.1×10 18-2.6×10 19 m -3.
|Original language||English (US)|
|Number of pages||11|
|Journal||Journal of Vacuum Science and Technology A: Vacuum, Surfaces and Films|
|State||Published - Jan 1 2004|