Plasma treatment apparatus and plasma treatment method

1. A plasma treatment apparatus including an inductively-coupled plasma torch unit, the inductively-coupled plasma torch unit comprising:

a chamber having an outside dielectric block having an opening portion which serves as a plasma ejection port at a bottom end of the outside dielectric block and an inside dielectric block, the inside dielectric block including:

an inside dielectric block main body disposed at a top end of the outside dielectric block and having a gas pipe that introduces gas into an inside of the chamber, the gas pipe being communicated with a gas supply pipe;

a protrusion provided in a protruding manner from the inside dielectric block main body; and

an inside taper portion provided at a front end of the protrusion;

a circular plasma generation area being formed between a side surface of the outside dielectric block and a side surface of the inside dielectric block;

a solenoid coil disposed laterally to a space which is formed between the inside dielectric block and the outside dielectric block, the plasma treatment apparatus further including:

a high-frequency power supply having a pulse modulation function which is connected to the solenoid coil and supplies a pulse-modulated high-frequency power to the solenoid coil; and

a base material mounting table disposed on a plasma ejection port side, wherein:

the chamber is circular and has a long shape;

the plasma ejection port is formed into a long linear shape;

the solenoid coil has a long shape;

a moving mechanism is provided to relatively move the chamber and the base material mounting table perpendicularly with respect to the longitudinal direction of the plasma ejection port;

the outside dielectric block includes an outside dielectric block main body having a plasma generation area formed inside and an outside taper portion having the plasma ejection port at the bottom end whose diameter becomes narrower in a direction from an opening portion of the outside dielectric block main body on a side of the base material mounting table toward the base material mounting table;

the taper portion has a flat edge parallel to a direction in which the chamber and the base material mounting table relatively move; and

a space formed between the inside dielectric block and the outside dielectric block comprises:

a first space between the inside dielectric block main body of the inside dielectric block and the outside dielectric block main body of the outside dielectric block;

a second space between the protrusion of the inside dielectric block and the outside dielectric block main body of the outside dielectric block; and

a third space between the inside taper portion of the inside dielectric block and the outside taper portion of the outside dielectric block,

the first space and the third space having smaller gaps than that of the second space.