Sheath analysis in collisional electronegative plasmas with finite temperature of positive ions

The sheath which occurs in front of a plane metallic surface immersed in an electronegative plasma is analysed taking into account the positive ion collisions and thermal motion. Collisions do not affect the equations of the sheath but have a significant influence on the initial conditions, which are obtained from the plasma solution. The combined influence of collisions and positive ion thermal motion on the sheath, the sheath thickness, the positive ion saturation current and the floating potential is analysed.