Abstract
It is confirmed, with the use of both a movable magnetic filter and a plasma grid, that plasma parameters (H2-CH4 or Ar-CH4 plasmas) are spatially well controlled. At any filter position, plasma parameters change steeply across the magnetic filter. Then, a plasma source is divided into two parts, i. e. a source plasma region (high density plasma with energetic electrons) and a diffused plasma region (low density and low temperature plasma without energetic electrons). The former is suitable for producing the reactive species and the latter for preparing thin films. In addition, plasma parameters in the diffused plasma are controlled by changing the plasma grid potential. The role of the magnetic filter (i. e. preferential reflection of energetic electrons) is also discussed by computer simulation.