Title :
Impact of Phase Shifted Coil Currents on Plasma Uniformity
Author :
Agarwal, Ankur ; Banna, Samer ; Todorow, Valentin ; Rauf, Shahid ; Collins, Ken
Author_Institution :
Etch Products Bus. Group of Appl. Mater. Inc., Sunnyvale, CA, USA
Abstract :
Plasma etching at sub-3x-nm nodes requires inductively coupled plasma (ICP) reactors to work within tight uniformity constraints. The characteristic donut shape of the ICPs is, however, visible on the wafer in a 20-60 mTorr range due to reduced plasma diffusion. Phase shifting of the coil currents in an ICP source has been used to improve plasma uniformity. Images of plasma properties with and without phase shift of coil currents are presented.
Keywords :
plasma materials processing; plasma simulation; plasma transport processes; sputter etching; ICP source; donut shape; inductively coupled plasma reactors; phase shifted coil currents; phase shifting; plasma etching; plasma properties; plasma uniformity; pressure 20 mtorr to 60 mtorr; reduced plasma diffusion; uniformity constraints; Coils; Etching; Inductors; Iterative closest point algorithm; Plasma properties; Shape; Inductively coupled plasma; phase shift; plasma etching; plasma modeling; plasma processing; plasma uniformity;
Journal_Title :
Plasma Science, IEEE Transactions on
Conference_Location :
5/5/2011 12:00:00 AM
DOI :
10.1109/TPS.2011.2140337
