Plasma treatment apparatus.

摘要

A plasma treatment apparatus is disclosed in which a sample (100) is placed on a cathode (24) held in an etching chamber (34) which is filled with CF4 gas with a pressure of about 10<-><2> torr. A high frequency voltage is applied between the cathode (24) and anode (20) to produce a plasma. A magnetic field having a component perpendicularly intersecting an electric field is generated above the cathode (24) by a magnetic field generator (60). A magnetic core (62) involved in the magnetic field generator has a combed cross section and is comprised of a plurality of coils (70). Every third coil is connected together to form three groups of coils. The three groups (72, 74, 76) of coils are respectively connected to the terminals of a 3-phase AC power source (82) having different phases. A high density plasma region is produced by a magnetic field. The electrons constituting the plasma are made to present a cycloid movement by the magnetic field, and generate a large number of ions upon collision with the molecules of CF4 gas. Since the magnetic field is shifted along the surface of the cathode (24), the sample (100) set on the cathode is uniformly etched by being evenly affected by a high density plasma region.