US 12,125,672 B2
Plasma processing method and plasma processing apparatus
Chishio Koshimizu, Miyagi (JP)
Assigned to Tokyo Electron Limited, Tokyo (JP)
Filed by Tokyo Electron Limited, Tokyo (JP)
Filed on Jul. 11, 2023, as Appl. No. 18/350,207.
Application 18/350,207 is a continuation of application No. 16/919,650, filed on Jul. 2, 2020, granted, now 11,742,180.
Claims priority of application No. 2019-130978 (JP), filed on Jul. 16, 2019.
Prior Publication US 2023/0360882 A1, Nov. 9, 2023
Int. Cl. H01L 21/00 (2006.01); H01J 37/248 (2006.01); H01J 37/32 (2006.01)
CPC H01J 37/32082 (2013.01) [H01J 37/248 (2013.01); H01J 37/32568 (2013.01)] 12 Claims
OG exemplary drawing
 
1. A plasma processing apparatus comprising:
a chamber;
a substrate support disposed in the chamber, the substrate support including:
a lower electrode; and
a conductive ring disposed closer to a side wall of the chamber than a substrate placed on the substrate support;
an RF power source configured to generate an RF power having a first frequency to generate a plasma in the chamber;
a bias power source configured to supply a bias to the lower electrode, the bias being a bias RF power having a second frequency less than the first frequency or a pulsed negative voltage which is periodically applied to the lower electrode at the second frequency, a waveform cycle of the bias defined by the second frequency including a first period in which a potential of the substrate is negative and a second period in which a potential of the substrate is equal to or greater than 0, the second frequency being not less than 50 kHz and not more than 27 MHz;
a power source device configured to apply a voltage to the conductive ring; and
a controller configured to control the power source device to apply a first voltage to the conductive ring in the first period in the waveform cycle and to apply a second voltage greater than the first voltage to the conductive ring in the second period in the waveform cycle, the second voltage having a positive polarity.