US 12,125,679 B2
Plasma processing apparatus and processing method
Chishio Koshimizu, Miyagi (JP); Gen Tamamushi, Miyagi (JP); Masahiro Inoue, Miyagi (JP); Yuto Kosaka, Miyagi (JP); and Shoichiro Matsuyama, Miyagi (JP)
Assigned to TOKYO ELECTRON LIMITED, Tokyo (JP)
Filed by Tokyo Electron Limited, Tokyo (JP)
Filed on Sep. 23, 2022, as Appl. No. 17/951,579.
Claims priority of application No. 2021-155740 (JP), filed on Sep. 24, 2021.
Prior Publication US 2023/0094655 A1, Mar. 30, 2023
Int. Cl. H01J 37/00 (2006.01); H01J 37/32 (2006.01)
CPC H01J 37/32211 (2013.01) [H01J 37/32165 (2013.01); H01J 37/32183 (2013.01); H01J 37/3244 (2013.01)] 11 Claims
OG exemplary drawing
 
1. A plasma processing apparatus comprising:
a chamber;
a substrate support provided in the chamber;
a bias power supply configured to supply an electrical bias energy to an electrode of the substrate support, in order to draw ions from a plasma generated in the chamber into the substrate placed on the substrate support, wherein the electrical bias energy has a bias frequency, and a cycle of the electrical bias energy has a time length which is a reciprocal of the bias frequency;
a matching box including a matching circuit;
a radio-frequency power supply configured to supply a radio-frequency power having a variable frequency into the chamber through the matching box in order to generate the plasma from a gas in the chamber, and adjust the variable frequency of the radio-frequency power in each of a plurality of phase periods within the cycle of the electrical bias energy;
a sensor configured to detect an electrical signal reflecting a deviation of a load impedance of the radio-frequency power supply from a matching state; and
a filter configured to generate a filtered signal by removing an intermodulation distortion component of the radio-frequency power and the electrical bias energy from the electrical signal in each of the plurality of phase periods.