Substrate processing apparatus and substrate processing method

A substrate processing apparatus, comprising:

• a chamber;
• a first electrode disposed in the chamber and holding a substrate on a main surface of the first electrode;
• a second electrode disposed in the chamber to face the first electrode;
• a RF power source applying to the first electrode a RF voltage whose frequency is equal to or higher than 40 MHz;
• a pulse voltage applying unit applying a pulse voltage to the first electrode by superimposing the pulse voltage on the RF voltage;
• a variable capacitance capacitor interposed between the first electrode and the pulse voltage applying unit and connected in series to the first electrode;
• a voltage measuring unit measuring a voltage of the first electrode or a plasma measuring unit measuring electron density of plasma;
• and
• a control unit changing electric charge capacitance of the variable capacitance capacitor according to a result of the measurement by the voltage measuring unit or the plasma measuring unit.

A substrate processing apparatus, comprising:

• a chamber;
• a first electrode disposed in the chamber and holding a substrate on a main surface of the first electrode;
• a second electrode disposed in the chamber to face the first electrode;
• a RF power source applying to the first electrode a RF voltage whose frequency is equal to or higher than 40 MHz;
• and
• a pulse voltage applying unit applying to the first electrode a voltage having a waveform in which a first period and a second period are repeated, by superimposing the voltage on the RF voltage, the first period having a pulse group waveform including N1 pieces of pulsed waveforms which are repeated with a break time t1 and a frequency ω1, and the second period being a break time t2 not including a pulsed waveform and longer than the break time t1.

A substrate processing apparatus, comprising:

• a chamber;
• a first electrode disposed in the chamber and holding a substrate on a main surface of the first electrode;
• a second electrode disposed in the chamber to face the first electrode;
• a RF power source applying to the first electrode a RF voltage whose frequency is equal to or higher than 40 MHz;
• a pulse voltage applying unit applying a pulse voltage to the first electrode by superimposing the pulse voltage on the RF voltage;
• a variable resistor provided between the pulse voltage applying unit and the first electrode;
• and
• a control unit controlling a resistance value R of the variable resistor.

A substrate processing method, comprising:

• holding a substrate to be processed on an electrode disposed in a chamber;
• applying to the electrode a RF voltage whose frequency is equal to or higher than 40 MHz;
• and
• applying to the electrode a pulse voltage decreasing in accordance with a lapse of time, by superimposing the pulse voltage on the RF voltage.

A substrate processing method, comprising:

• holding a substrate to be processed on an electrode disposed in a chamber;
• applying to the electrode a RF voltage whose frequency is 40 MHz or higher;
• and
• applying to the electrode a voltage having a waveform in which a first period and a second period are repeated, by superimposing the voltage on the RF voltage, the first period having a pulse group waveform including N1 pieces of pulsed waveforms which are repeated with a break time t1 and a frequency ω1, and the second period being a break time 2 not including a pulsed waveform and longer than the break time t1.