PURPOSE: To form a homogeneous film at high speed by a method wherein a mesh electrode used to accelerate an ion is placed in front of a substrate support stage in a reaction chamber and a screen electrode capable of reducing an influence by the mesh electrode by adjusting a potential is placed inside a plasma generation chamber in order to separate a control operation of a plasma state from a control operation of an ion speed.

CONSTITUTION: This is An electron cyclotron resonance plasma CVD apparatus constituted in the following way: a plasma generation chamber 1 where a means to form a magnetic line of force is provided at the outside and into which microwaves are introduced is interlinked with a reaction chamber 2 which houses a support stage 7 of a substrate 10 on which a thin film is to be deposited; a plasma generated in the plasma generation chamber 1 is diffused to the direction of the magnetic line of force. In this apparatus the following are provided: a mesh electrode 11 which is situated on the side of the plasma generation chamber 1 ot the substrate support stage 7 and to which an arbitrary voltage can be applied; a screen electrode 12 which surrounds an inner wall of the plasma generation chamber 1, which is equipped with a slit parallel to a polarization plane of microwaves and to which an arbitrary voltage can be applied. By this setup, it is possible to enhance a film-formation speed without degrading the film quality.