Plasma process apparatus

摘要

A vacuum chamber contains a first electrode for supporting a wafer, and a second electrode opposing the first electrode. A supply system and an exhaustion system are connected to the vacuum chamber. The system supplies a reactive gas into the chamber, and the system exhaust the used gas from the chamber. A radio-frequency power supply is connected to the first electrode, for supplying power between the electrodes to generate an electric field E. An annular magnet assembly is provided around the chamber, for generating a magnetic field B which has a central plane intersecting with the electric field E. The magnet assembly has a plurality of magnet elements which have different magnetization axes in the central plane of the magnetic field. Electrons drift due to a force resulting from an outer product (ExB) of the electric field E and the magnetic field B. The central plane of the magnetic field B is shifted upwards from the target surface of the wafer, such that the magnetic force lines of the magnetic field intersect with the target surface of the substrate.