Hard mask deposition using direct current superimposed radio frequency plasma

A plasma processing apparatus comprising:

• a plasma processing chamber;
• a substrate holder disposed in the plasma processing chamber, the substrate holder being a lower electrode of the plasma processing chamber;
• a radio frequency (RF) electrode disposed above the substrate holder within the plasma processing chamber, the RF electrode being an upper electrode of the plasma processing chamber;
• an RF power source electrically coupled to the RF electrode through an impedance matching circuit, the RF power source being configured to supply continuous wave RF power to the RF electrode, the continuous wave RF power comprising a frequency greater than 60 MHz;
• and
• a direct current (DC) power source separate from the RF power source and electrically coupled to the RF electrode through an RF choke, the DC power source being configured to supply continuous wave DC power to the RF electrode, the continuous wave DC power being supplied concurrently with the continuous wave RF power.

A plasma processing apparatus comprising:

• a plasma processing chamber;
• a substrate holder disposed in the plasma processing chamber, the substrate holder being a lower electrode of the plasma processing chamber;
• a radio frequency (RF) electrode disposed above the substrate holder within the plasma processing chamber, the RF electrode being an upper electrode of the plasma processing chamber;
• an RF power source electrically coupled to the RF electrode through an impedance matching circuit, the RF power source being configured to supply continuous wave RF power to the RF electrode, the continuous wave RF power comprising a frequency in the very high frequency (VHF) range;
• and
• a direct current (DC) power source separate from the RF power source, the DC power source being configured to supply continuous wave DC power to the plasma processing chamber through an RF choke, the continuous wave DC power being supplied concurrently with the continuous wave RF power.