US 12,394,600 B2
Balanced RF resonant antenna system
Qiang Wang, Austin, TX (US); Michael Hummel, Austin, TX (US); Peter Lowell George Ventzek, Austin, TX (US); Shyam Sridhar, Austin, TX (US); and Mitsunori Ohata, Taiwa-cho (JP)
Assigned to Tokyo Electron Limited, Tokyo (JP)
Filed by Tokyo Electron Limited, Tokyo (JP)
Filed on Apr. 28, 2023, as Appl. No. 18/308,877.
Prior Publication US 2024/0363310 A1, Oct. 31, 2024
Int. Cl. H01J 37/32 (2006.01); H01Q 5/10 (2015.01)
CPC H01J 37/32183 (2013.01) [H01J 37/32091 (2013.01); H01Q 5/10 (2015.01)] 20 Claims
OG exemplary drawing
 
1. A plasma processing system, comprising:
a plasma chamber;
an RF source configured to generate a forward RF wave;
a matching circuit coupled to the RF source, the matching circuit configured to provide matching for the RF source;
a balun having unbalanced terminals coupled to the matching circuit; and
a resonating antenna, the resonating antenna configured to generate plasma within the plasma chamber, the resonating antenna having:
a first spiral resonant antenna having an electrical length corresponding to a quarter of a wavelength of a frequency of the forward RF wave, the first spiral resonant antenna having a first end and a second end, the first end coupled to a first balanced terminal of the balun and the second end that is open circuit, and
a second spiral resonant antenna having an electrical length corresponding to the quarter of the wavelength of the frequency of the forward RF wave, the second spiral resonant antenna having a first end and a second end, the first end coupled to a second balanced terminal of the balun and the second end that is open circuit, wherein the first spiral resonant antenna and the second spiral resonant antenna are arranged in a symmetrically nested configuration having a same center point.