US 12,306,044 B2
Optical emission spectroscopy for advanced process characterization
Sergey Voronin, Albany, NY (US); Blaze Messer, Albany, NY (US); Yan Chen, Fremont, CA (US); Joel Ng, Fremont, CA (US); Ashawaraya Shalini, Fremont, CA (US); Ying Zhu, Fremont, CA (US); and Da Song, Albany, NY (US)
Assigned to Tokyo Electron Limited, Tokyo (JP)
Filed by Tokyo Electron Limited, Tokyo (JP)
Filed on Sep. 20, 2022, as Appl. No. 17/948,407.
Prior Publication US 2024/0094056 A1, Mar. 21, 2024
Int. Cl. G01J 3/443 (2006.01); H01J 37/32 (2006.01)
CPC G01J 3/443 (2013.01) [H01J 37/32146 (2013.01); H01J 37/32972 (2013.01); H01J 2237/24485 (2013.01); H01J 2237/24507 (2013.01); H01J 2237/24585 (2013.01); H01J 2237/334 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method of characterizing a plasma in a plasma processing system, the method comprising:
generating a pulsed plasma in a plasma processing chamber of the plasma processing system, the pulsed plasma being powered with a pulsed power signal, each pulse of the pulsed plasma comprising three periods: an overshoot period, a stable-ON period, and a decay period;
performing cyclic optical emission spectroscopy (OES) measurements for the pulsed plasma, the cyclic OES measurements comprising:
obtaining first OES data during one of the three periods from more than one pulses of the pulsed plasma; and
obtaining a characteristic of the pulsed plasma for the one of the three periods based only on the first OES data.