An apparatus for generating plasma is disclosed. The apparatus comprises: a plasma chamber; pairs of parallel plate electrodes; and a power supply for applying high-frequency powers on the pairs of electrodes. The frequencies of the high-frequency powers and the phase difference between the high-frequency powers are adjusted so as to cause each of electrons in the plasma to move in a circular path. A dense and highly uniform plasma is generated at a low pressure level, by utilizing the phenomenon of the oscillation, revolution or cycloidal motion of electrons in a high-frequency electric field formed between the parallel plate electrodes. This plasma is suitable for etching in the LSI fabrication process.