A plasma processing apparatus includes a first radio frequency (RF) power
supply unit for applying a first RF power for generating a plasma from a
processing gas to at least one of a first and a second electrode which
are disposed facing each other in an evacuable processing chamber. The
first RF power supply unit is controlled by a control unit so that a
first phase at which the first RF power has a first amplitude for
generating a plasma and a second phase at which the first RF power has a
second amplitude for generating substantially no plasma are alternately
repeated at predetermined intervals.