US 12,142,452 B2
Systems and methods for monitoring faults, anomalies, and other characteristics of a switched mode ion energy distribution system
Daniel Carter, Fort Collins, CO (US); Victor Brouk, Fort Collins, CO (US); and Daniel J. Hoffman, Fort Collins, CO (US)
Assigned to Advanced Energy Industries, Inc., Denver, CO (US)
Filed by Advanced Energy Industries, Inc., Fort Collins, CO (US)
Filed on Nov. 17, 2021, as Appl. No. 17/528,268.
Application 17/528,268 is a continuation of application No. 15/495,513, filed on Apr. 24, 2017, granted, now 11,189,454.
Application 15/495,513 is a continuation of application No. 13/597,093, filed on Aug. 28, 2012, granted, now 9,685,297, issued on Jun. 20, 2017.
Prior Publication US 2022/0157555 A1, May 19, 2022
This patent is subject to a terminal disclaimer.
Int. Cl. H01J 37/08 (2006.01); G01N 27/06 (2006.01); H01J 37/32 (2006.01)
CPC H01J 37/08 (2013.01) [G01N 27/06 (2013.01); H01J 37/32944 (2013.01); H01J 37/3299 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A method for monitoring a plasma processing chamber, the method comprising:
applying, with a bias supply, a modified periodic voltage function to an electrical node, wherein each cycle of the modified periodic voltage function includes four portions: a first portion with a voltage that increases to a second portion that has a positive voltage relative to an onset of the voltage of the first portion, a third portion starting at an end of the second portion with a voltage drop, ΔV, and a fourth portion,

OG Complex Work Unit Math
 that includes a negative voltage ramp from an end of the third portion; and
monitoring, with the bias supply, at least the fourth portion of the modified periodic voltage function over multiple cycles;
calculating, based upon the monitoring, ion current in the plasma processing chamber; and
utilizing the calculation of ion current to monitor conditions in the plasma processing chamber.